20-11-2006

12:21

Pagina 1

VOL. 16 - (2) - OCTOBER 2006

Whatever the treatment, we don’t play around with urinary security.

ISSN 1018-2357

The European Journal of

Companion Animal Practice

THE EUROPEAN JOURNAL OF COMPANION ANIMAL PRACTICE - Vol. 16 - (2) - October 2006

*Except RENAL (in dry form)

From now on, the entire Veterinary Diet Feline* range bears the S/O index logo, which guarantees optimal urinary security.

- Photo : Y. Lanceau - 06/2006.

15410 cover ITALIE

Long-term analysis of the progression of hip arthrosis after triple pelvic osteotomy

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Retrospective study of owners’ perception on home monitoring of blood glucose in diabetic dogs and cats

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Inner ear dysfunction related to ear disease in dogs and cats

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Rehabilitation Therapies for musculoskeletal and spinal disease in Small Animal Practice

137

THE OFFICIAL JOURNAL OF FECAVA Federation of European Companion Animal Veterinary Associations www.fecava.org Anno 16, Numero 2, 2e Semestre 2006 Spedizione in abbonamento postale - 45% Art. 2 Comma 20/B - Legge 662/96 - Filiale di Piacenza

Volume 16 (2) October 2006 The Official Journal of the Federation of European Companion Animal Veterinary Associations (FECAVA).

EDITOR Dr. Keith Davies 43, Hill Top Road - Newmillerdam GB-WF2 6PZ Wakefield Tel.: (44) 1924 250486 (UK) (33) 4 68 39 50 29 (F) Fax: (44) 1924 259572 Email: [email protected] PRODUCTION COMMITTEE Dr Ellen BJERKÅS, FECAVA President Dr. Keith DAVIES, Editor Dr. Joaquin ARAGONES Dr. Peter STERCHI Dr. Tiina TOOMET Dr. Johan VAN TILBURG Dr. Simon KLEINJAN EDITORIAL BOARD (FOR NEW WORK) Dermatology Didier-Noël CARLOTTI (F) Cardiology Anna TIDHOLM (S) Internal medicine Åke HEDHAMMAR (S) Orthopaedics Aldo VEZZONI (I) Surgery Simon ORR (GB) Imaging Ingrid GIELEN (B) Eiliv SVALASTOGA (DK) Reproduction Stefano ROMAGNOLI (I) Dentistry Peter FAHRENKRUG (D) Ophthalmology Ellen BJERKÅS (N) Neurology Andre JAGGY (CH) Endocrinology Mike HERRTAGE (GB) Oncology Jane DOBSON (GB) New Material should be sent to: Prof. Ellen BJERKÅS, Norwegian School of Veterinary Science, PO Box 8146-Dep, N- 0033, Oslo. ADVERTISEMENT BOOKINGS Sould be sent to: The Editor (see above) CIRCULATION Members of the Associations belonging to the Federation of European Companion Animal Veterinary Associations receive the European Journal of Companion Animal Practice at no charge (30,000 copies). PURCHASE OF COPIES For others interested in purchasing copies the price is 52 € per Volume (2 issues). Orders should be sent to: FECAVA HQ, rue Defacqz 1, B-1000 Brussels THANKS The production Committee of EJCAP thanks: Dr. Owen Davies Dr. Tim Hutchinson Dr. Edmund Shillabeer Dr. John E.F. Houlton who have spent time correcting the translations. Editore SCIVAC-AIVPA, Via Trecchi 20 I-26100, CREMONA, Italia. Inscrizione Registro Stampa del Tribunale di Cremona N.257 del 1/2/1991; Spedizione in abbonamento postale. 45% Art. 2 Comma 20/B - Legge 662/96 - 2er semestre 2006 - Filiale de Piacenza. Direttore Responsabile : Antonio MANFREDI. Roto Smeets GrafiServices, p.o. box 7052, 3502 KB Utrecht, The Netherlands. Tel +31 (30) 282 28 22

The European Journal of Companion Animal Practice (EJCAP)

Contents The Federation of European Companion Animal Veterinary Associations (FECAVA) Editorial News

114 117 120

EAR, NOSE AND THROAT Inner ear dysfunction related to ear disease in dogs ans cats G. ter Haar

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AFTERCARE AND NURSING Rehabilitation Therapies for musculoskeletal and spinal disease in Small Animal Practice M. Owen

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ORTHOPAEDICS Diagnostic and genetic aspects of patellar luxation in small and miniature breed dogs in Austria B. Vidoni, I. Sommerfeld-Stur, E. Eisenmenger

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Long-term analysis of the progression of hip arthrosis after triple pelvic osteotomy Th. Dembour , J-L Chancrin

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Stratification, blinding and placebo effect in a clinical trial of gold bead implantation in Canine Hip Dysplasia G.T. Jaeger, S. Larsen, L. Moe

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ENDOCRINLOGY Retrospective study of owners’ perception of home monitoring of blood glucose in diabetic dogs and cats I. Van de Maele, N. Rogier, S. Daminet

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Diagnostic specificity of canine thyrotropin in the diagnosis of Hypothyroidism in dogs F. Boretti, C.E.Reusch

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Bilateral adrenalectomy in a ferret (Mustela putorius furo) with hyperadrenocorticism J. Martorell , Y.Espada , A. Ramis

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URINOGENTIAL SYSTEM Treatment of pyometra in the bitch: A survey among Norwegian small animal practitioners V. Rootwelt-Andersen, W. Farstad

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DERMATOLOGY Contemporary aspects of the immunopathogenesis of autoimmune diseases of the epidermal basement membrane in the dog E. I. Papadogiannakis

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Book Reviews

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Calendar of main European national meetings and other continuing education opportunities

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Secretariat or address to contact for information

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DISCLAIMER “The Federation of European Companion Animal Veterinary Associations and the Production Committee of the European Journal of Companion Animal Practice accept no responsibility for any omissions and/or errors in information printed in this journal.We specifically draw readers attention to the need to follow instructions of manufacturers products. In any specific situation readers are strongly advised not merely to rely on the material contained in the journal. Any views and opinions expressed are those of the writer and not the Federation or the Production Committee.”

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The Federation of European Companion Animal Veterinary Associations (FECAVA) FECAVA Headquarter’s address: C/O Federation of Veterinarians of Europe rue Defacqz, 1 B-1000 Brussels Tel: +32 2 538 29 63 – Fax: +32 2 537 28 28 FECAVA Website: www.fecava.org

Participating Associations:

SMASAP Serbia and Montenegro Association of Small Animal Practitioners Director: Dr. Denis NOVAK SSAVA Swedish Small Animal Veterinary Association Director: Dr. Anne CARLSWÄRD SVK/ASMPA Schweizerische Vereinigung für Kleintiermedizin/Association Suisse pour la Médecine des Petits Animaux Director: Dr. Peter STERCHI SZVMZ Slovensko Zdruzenje Veterinariev Za Male Zivali Director: Dr. Bojan ZORKO TSAVA Turkish Small Animal Veterinary Association Director: Dr. Mustafa AKTAS USAVA Ukrainian Small Animal Veterinary Association Director: Dr. Vladlen Mykhaylovich USHAKOV VICAS Veterinary Ireland Companion Animal Society Director: Dr. Peter A. MURPHY VÖK Vereinigung Österreichischer Kleintier mediziner Director: Dr. Silvia LEUGNER

AFVAC Association Française des Vétérinaires pour Animaux de Compagnie Director: Dr. Jean-François ROUSSELOT AIVPA Associazione Italiana Veterinari Piccoli Animali Director: Dr. Guiseppe TRANCHESE APMVEAC Associação Portuguese de Médicos Veterinários Especialistas em Animais de Companhia Director: Dr. Joaquim Vieira LOPEZ AVEPA Associatión Veterinaria Española de Especialistas en Pequeños Animales Director: Dr. Juan Francisco RODRIGUEZ BASAV Bulgarian Association of Small Animal Veterinarians Director: Dr. Boyko GEORGIEV BHSAVA Bosnia and Herzegovina Small Animal Veterinary Association Director: Dr. Josip KRASNI BSAVA British Small Animal Veterinary Association Director: Dr. Ian MASON CSAVA Czech Small Animal Veterinary Association Director: Dr. Jiri BERANEK CSAVS Croatian Small Animal Veterinary Section Director: Dr. Davorin LUKMAN DSAVA Danish Small Animal Veterinary Association Director: Dr. Joergen MIKKELSEN ESAVA Estonian Small Animal Veterinary Association Director: Dr. Tiina TOOMET FAVP Finnish Association of Veterinary Practitioners Director: Dr. Kai SITTNIKOW GSAVA German Small Animal Veterinary Association Director: Dr. Peter FAHRENKRUG HSAVA Hungarian Small Animal Veterinary Association Director: Dr. Julianna THUROCZY HVMS Hellenic Veterinary Medical Society Director: Dr. Katerina LOUKAKI LAK Letzebuerger Associatioun vun de Klengdeiere - Pracktiker Director: Dr. Liz JUNIO LSAPS Latvian Small Animal Practitioners Section of The Latvian Association of Veterinarians Director: Dr. Lita KONOPORE LSAVA Lithuanian Small Animal Veterinary Association Director: Dr. Saulius LAURUSEVICIUS MSAVA Macedonion (Fyrom) Small Animal Veterinary Association Director: Dr. Pero BOVINOVSKI MVA Malta Veterinary Association Director: Dr. L. Vella, Director: Dr. A. GRUPETTA NACAM Netherlands Association for Companion animal Medicine Director: Dr. Leen den OTTER NSAVA Norwegian Small Animal Veterinary Association Director: Dr. Kjetil DAHL PSAVA Polish Small Animal Veterinary Association Director: Dr. Jerzy GAWOR RSAVA Russian Small Animal Veterinary Association Director: Dr. S. SEREDA SAVAB Small Animal Veterinary Association of Belgium Director: Dr. J. van TILBURG SCIVAC Società Culturale Italiana Veterinari per Animali da Compagnia Director: Dr. Dea BONELLO SKSAVA Slovakia Small Animal Veterinary Association Director: Dr. Tibor BRAUNER

Associate Associations: EAVS

European Association for Veterinary Specialisation Contact: Dr. Hans KOCH ECVD European College of Veterinary Dermatology Contact: Dr. Dominique HERIPRET ECVS European College of Veterinary Surgeons Mrs Monika GUTSCHER ESVC European Society of Veterinary Cardiology Contact: Dr. Chris AMBERGER ESFM European Society for Feline Medicine Claire BESSANT ESVCE European Society of Veterinary Clinical Ethology Contact: Dr. Sarah HEATH ESVD European Society of Veterinary Dermatology Contact: Dr. Chiara NOLI ESVIM The European Society of Veterinary Internal Medicine Contact: Dr. Rory BELL ESVN European Society of Veterinary Neurology Contact: Dr. Gualtiero GANDINI ESVOT European Society of Veterinary Orthopaedics & Traumatology Contact: Dr. Aldo VEZZONI EVDS European Veterinary Dental Society President: Dr. Margarita GRACIS EVSSAR European Veterinary Society for Small Animal Reproduction Contact: Dr. Alain FONTBONNE FECAVA officers: Dr. Ellen BJERKÅS Dr. Andrew BYRNE Dr. Simon KLEINJAN Dr. Simon ORR Dr Johan van TILBURG

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NSAVA VICAS NACAM BSAVA SAVAB

President Vice-President Senior Vice-President Secretary Treasurer

Editorial EJCAP, the Fifteen years - past and the future

The basic philosophy of EJCAP has changed little, though its evolution in its first 15 years has been constant and exciting. The underlying aim has always been to bring to European Companion Animal Veterinarians the best work and knowledge from all parts of Europe, and from European colleagues working worldwide. The EJCAP , through the medium of the English language, enables Veterinarians in Norway or Bulgaria, to benefit from knowledge and experience in Portugal and Ireland! At first all papers in the Journal were translated reprints, member countries submitting what they considered the best work from their county, previously printed in other Journals, usually not in English. The best of these papers were selected, translated into English and published in EJCAP. In recent years submission of original work from Europe has been encouraged. An Editorial Board has been set up to rigorously peer review papers. Commissioned work has resulted in a series of practical papers of great relevance to readers in general practice. Papers have been published based on lectures given at FECAVA European Congresses, FECAVA Symposia and CE Courses, keeping readers up to date in a practical way. More recently, a series of papers on Practice management, sometimes highlighting different types of practice have been featured. It was decided some years ago that the Journal should concentrate on practical papers, rather than attempting to go down the road of trying to achieve a high citation rating by publishing cutting edge research. In 2004/5 a survey of readers was conducted and very positive feedback resulted. It was clear that our decision to feature mainly practical papers was a good one. Some of the improvements suggested in the survey have already been implemented. The new style cover and easy reference colour coding of paper topics are some examples of this. In this issue new styles for the News and paper layout are introduced, hopefully making our pagers more reader friendly. Exciting FECAVA projects such as Microchip standardisation, Veterinary Nursing Manuals in different languages and the Blue Dog project (an interactive educational video for children) have all been brought to the attention of our 30,000 readers through EJCAP, a unique communication tool in Veterinary Europe. But what of the future? The evolution must and will continue. A third annual issue is a not too distant reality, probably focusing on a specific topic and produced by a sub-editor and production team. The cost of production of this could be largely funded by the generosity of our advertisers, but distribution would cost readers in the region of 2.5 € per issue. Alternatavely, this issue could be published solely on line. What do you think of these alternatives? The future of EJCAP must embrace the wishes of readers. Please join the increasing number of those providing feedback by contacting me by e-mail: [email protected] . Only by more of you doing this can we ensure another fifteen successful years! Keith Davies, Editor

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EJCAP - Vol. 16 - Issue 1 - April 2006 FECAVA NEWS

FECAVA NEWS Council meeting returns to Paris FECAVA Council returned to its roots after more than 15 years of activity by holding the its May meeting at the Headquarters of AFVAC. The meeting was well attended and had a full agenda. A short report on two important items discussed is given below.

’The Board also felt that there might be some feeling of frustration among the Directors (the national representatives), because the FECAVA aims and objectives were not clearly defined’, president Dr. Ellen Bjerkås explained. To find out if this hypothesis reflected the situation the Board decided to ask opinion within the organization. A questionnaire was sent out to 15 persons who have shown a special interest in the progress of FECAVA: Past Presidents, Board members and some dedicated Directors. Based on the answers received a workshop involving all the Directors was then held at the Council meeting in Paris in May. ’Both the workshop and the answers to the questionnaire confirmed our feeling that there is little alignment of what FECAVA stands for. That means that we have an important job in front of us’, said FECAVA president Dr. Bjerkås.

Need for a revised Strategic Plan This was the first Council meeting with new President Dr. Ellen Bjerkås at the helm. In her opening address, she commented that although FECAVA remained a strong and active association, it was time to draw up a framework outlining a clear strategy for the years to come. New Directors found it difficult to come to terms with all the information they had to assimilate. It was proposed to devise brief ’summary job description’ sheets that would fill this gap when the people that ’knew everything’ were no longer active. Ellen stressed that it was important that FECAVA remained active within FVE and UEVP and took the lead on European companion animal issues.

FECAVA brings its Vision into Focus From Astrid Bjerkås, Writing for FECAVA

The following questions were asked in the questionnaire: 1. If you had to choose the 3 most important objectives of FECAVA for the next 3 years, what would they be? Please rank them in order of importance. 2. What are the strengths that the FECAVA Council has to achieve the objectives? 3. What are the biggest obstacles that could hinder FECAVA achieving its objectives? 4. Indicate the ’one’ greatest achievement of FECAVA in the past 10 years. 5. What is the number one ’driver’ (motivation) to be a FECAVA board member?

FECAVA Directors in ‘workshop session’ at the AFVAC HQ in Paris.

After 15 years of activity and significant expansion, the FECAVA Board felt that it was now time to scrutinize the FECAVA’s aims and ideas to see if they are still valid or if the time has come for a renewal of thoughts. ’The board felt that there was not full agreement within the organization on what the main tasks of FECAVA should be and as to whether our Federation should be political, educational or both.

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6. Suggestions/ Ideas that can make a difference to FECAVA. The questions below were asked in the workshop: 1. What are the FECAVA core values? 2. What makes FECAVA unique? 3. Who are FECAVA’s ’clients’?

Vision and results Dr. Betina Rama is assisting FECAVA in the process of defining FECAVA’s aims and objectives. Dr. Rama, an Argentinean veterinarian, is a human resources professional working with Procter and Gamble in Geneva, Switzerland, specialising in ’Change Management’ and ’Strategy.’ Dr. Rama is also familiar with international veterinary associations through her previous positions and as a member of the organisation of the 1998 WSAVA Congress in Buenos Aires. She explains why it is vital for an organisation to have a clear idea of its objectives saying :. ’A vision inspires and motivates the people involved to work together to solve the tasks in hand. A clear vision is absolutely necessary if you want to work efficiently, and last but not least a vision is essential to differentiate yourself from other organizations and institutions’.

Next steps Based on the answers given in the Paris workshop and in the questionnaire the board will now, in cooperation with Dr. Rama, decide on the next steps to be taken. ’FECAVA has now realized that because of a lack of agreement on the FECAVA vision, neither the goals nor the priorities are clear. My advice is that the board should ask the Directors to go back to their countries and touch base with their own national organisations and the local members and find out/ discuss what they need from FECAVA. In my opinion the board should assist the Directors with the necessary tools to complete the task, and preferably the national debates should be completed and summarised within a set period of time’, Dr.Betina Rama advises.

Dr. Bjerkås replied that these are among the questions that the board now needs to address. ’The workshop and the questionnaire were the first step in the process which we expect will last for 1-2 years. We are thankful to the Directors, to those who answered the questionnaire and to Betina Rama for giving us a good base for this important process’. The FECAVA board will continue the discussion of these matters at its next meeting Prague in October.

Health Support Structures in Europe – a preliminary report Some countries already have organised structures to support veterinarians who have health or other problems. For example, the UK has a Veterinary Benevolent Fund, a charity offering a variety of support services to veterinary professionals including: 1. Financial support for veterinarians and their families if a veterinarian is ill, unable to work or has died and dependants are consequently are struggling to cope from day to day. 2. The Vet Helpline - a confidential ’listening ear’ telephone service manned by volunteer veterinarians and their spouses to listen to veterinarians struggling with health issues of any kind and to refer them on to appropriate agencies 3. The Veterinary Surgeons Health Support Programme, which offers services to veterinarians suffering from alcohol and/or drug abuse problems and related addictions such as gambling, sex addiction, eating disorders etc and their resulting mental health problems. In addition, there are ongoing consultations to address the very high rate of suicide in the profession with the hope of offering solutions before suicide is contemplated. Thirteen associations responded to a questionnaire on this subject. 6/13 claimed to have some form of benevolent society, whereas only 2/13 reported having a telephone helpline and a support structure for veterinary surgeons with problems such as addictive disease. In most countries it seems that it is left to the veterinarian’s personal choice as to whether or not to take some form of insurance at his/her

FECAVA NEWS

EJCAP - Vol. 16 - Issue 2 October 2006

own expense to give support in times of need.

consists of six members drawn from nursing course providers, accreditation bodies and the veterinary profession. The DASVENT project members and Acovene have completed drafts of the Accreditation policies and procedures and also a list of competencies. The next stage of this project is to carry out a trial visitation to colleges participating in the project in order to test and evaluate the practicality and effectiveness accreditation procedures. These visitation panels will consist of four people including a veterinary surgeon and veterinary nurses from the host countries national veterinary and veterinary nursing associations as well as two members of the ACOVENE committee. The pilot visitations will be complete by June 2007. The project is scheduled to conclude in September 2007. FECAVA is a participant in this project and holds a position on the ACOVENE committee.

FVE Conference on Veterinary Education This took place in Brussels March 29/30 2006. The objectives were to review veterinary education in Europe and determine what veterinary skills our society required. The evaluation process for veterinary teaching establishments was reviewed and the relevance of Bologna Declaration on future veterinary education was discussed. The guidelines to what constitutes a valid veterinary qualification is laid down by the EU commission in Dir 2005/36/EC which came into force in October 2005 and should be transposed into national legislation before October 2007. The legal right to practice veterinary medicine is determined by the statutory body in each country. With regard to the visitation and evaluation system, of the 95 member establishments, 47 had been evaluated and 39 approved.

Veterinary nursing DASVENT Meeting March 2006 The members of the DASVENT project met in Geel, Belgium on May 19th. This project aims to establish a voluntary accreditation scheme for Veterinary Nursing Education in Europe. The project so far has agreed a memorandum of understanding between the partners that defines the scope and objectives of the project. A project specific accreditation committee of veterinary nursing education (ACOVENE) (www.acovene.org ) has been established for the duration of the DASVENT project. This committee

FECAVA Policy Statements The following FECAVA Policy statements have been adopted previously, and are available on the FECAVA Website: www. fecava.org – look in ’Newsflash’ or ’Policy Statements’. – Mutilations in Companion Animals – Neutering Dogs and Cats – Permanent Identification in Companion Animals – The Training of Veterinary Nurses – Animal Breeding Two new policy statements were adopted at the May 2006 Council meeting:

FECAVA Policy Statement - Cloning of Companion Animals 1. FECAVA strongly feels that it is unethical to clone companion animals purely to provide pets with similar characteristics. 2. FECAVA recognises that there may be medical and scientific advantages obtained from cloning companion animals. 3. Any such cloning procedure should be subject to the normal ethical controls as regulated by the European Convention on the use of animals in scientific procedures.

FECAVA Policy Statement – The Availability of Medicines Andrew Byrne – the ACOVENE FECAVA Representative

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1. FECAVA recognizes the paramount importance of the role of veterinarians

FECAVA NEWS

2.

3.

4.

5.

in the relief of suffering and the promotion of welfare of companion animals. To ensure this goal, FECAVA recommends that the authorization of medicines to relieve suffering in companion animals should be facilitated to provide easy access throughout Europe to the medicines vital to animal welfare. FECAVA reconfirms that Companion Animal medication does not represent any risk to the human population through food contamination. FECAVA is aware of the great responsibility vested in its members to protect and ensure the welfare of companion animals. In accepting that responsibility, FECAVA strongly recommends the introduction of legislation to allow for full availability of the medicines necessary to ensure good veterinary practice for these animals. FECAVA recognizes the desire of the EU Parliament and Council to achieve this goal when it stated clearly in the EU Directive 2004/28/ EC on Veterinary Medicines in section 21 of the Introduction that ’the administrative procedures for supplying medicinal products for pets, on the other hand, should be simplified. FECAVA urges the governments of member states to reflect this aspiration in their relevant regulations

Blue Dog Dog Bite Prevention Programme The Blue Dog educational resource consisting of written parent guide and interactive CDRom will be launched during the FECAVA/ WSAVA / CSAVA Congress held in Prague in October. Readers will remember that this is aimed at children between 3 – 6 yeas of age, helping them, with parental help, to avoid potential risk situations when interacting with their family pet. A unique feature of the project is that selected scenes of the CD have been scientifically assessed by Dr Kerstin Meints of the Psychology Department, University of Lincoln UK, to show whether children of this age learn from the CD. The research was generously funded by FECAVA and NACAM, with an additional grant from BSAVA. The results were very positive, and will be

Internationaal Congres over het Gedrag en Welzijn van Gezelschapsdieren Welfare and behaviour The science behind the art

Merelbeke Faculteit Diergeneeskunde Organisatie van VDWE, ECVBM-Ca en ESVCE

Alle aanvullende informatie: www.behaviour2006ghent.be

presented at the Prague congress. A summary of the work will be published in a subsequent issue of EJCAP. Further information about the Blue Dog can be found on the website: www.thebluedog.org The Blue Dog Trust has been set up as a non-profit legal entity to mange the project. The next phase is to find partners in different countries, who would be keen to translate, produce and distribute their language version in their own country. A choice of contractual arrangements is available. For more information contact:

Help needed to gain a UN Declaration for animals This initiative is being promoted by the World Society for the Protection of Animals (WSPA). The objective of the Universal Declaration on Animal Welfare campaign is to achieve a global statement at the United Nations (UN) that recognizes animals as sentient beings, capable of experiencing pain and suffering, and animal welfare as an issue of importance as part of the social development of nations worldwide.

The Blue Dog Trust 196 Hall Lane Upminster Essex GB-RM14 1UY

UN Declarations are used to declare certain aspirations at global level. It is important to emphasise that although such declarations are not legally binding, they have led to increased recognition of their respective issues by governments throughout the World.

International welfare and behaviour conference in Ghent

A five nation governmental steering committee comprising representatives from the following UN member states; Costa Rica, Kenya, India, Czech

Three groups (ESVCE, VDWE and ECVBM-CA) jointly hosted a three day international conference in the historic city of Ghent in Belgium in September 2006. The theme was ’Welfare and Behaviour – the science behind the art’, and this was well covered by a galaxy of international speakers from Europe, USA and Australia. Following the plenary sessions, the delegates were divided into separate sessions looking in more detail into aspects of welfare relating to: – Shelter animals – Animals working in Social, Therapeutic and Educational settings – Animals working in public services

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Ray Butcher was one of the first to sign the WSPA’s global petition

EJCAP - Vol. 16 - Issue 2 October 2006 Republic & Philippines met and agreed to champion the initiative amongst governments in their region to build support for a planned Ministerial conference in 2007. This is supported by the OIE (representing Chief Veterinary Officers from approx 167 countries worldwide) who feel it is complementary to their own initiatives. WSPA launched a global petition in support of this initiative in June 2006, using the simple statement ’ANIMALS MATTER TO ME’. The aim is to collect 10 million signatures – you can help by going on line at: www.animalsmatter.org The petition will be handed into the United Nations and it is hoped that a global voice of millions should heavily influence an institution built on the premise of representing the people.

Diary Dates – future congresses 2007 FECAVA/CSAVS Dubrovnik March 28 – April 1 Its is now autumn, with the prospect of a long cold winter ahead! So why not look forward to the springtime and the return of the sun? And where better than in the beautiful and historic city of Dubrovnic, Croatia. And while on the subject of future Congresses, the FECAVA congress of 2009 will return to Lille where it will be hosted jointly by the small animal associations of France, Belgium and Luxemburg. More information is given on pages 190 and 203 2008 FECAVA/WSAVA/ VICAS Dublin Ireland 20-24 August 2008 2009 FECAVA/SAVAB/LAK And while on the subject of future Congresses, the FECAVA congress of 2009 will return to Lille where it will be hosted jointly by the small animal associations of France, Belgium and Luxemburg. Why not get your diaries out now and plan your future CE by looking on pages 209-210!

Microchips working effectively Importance of regular scanning More and more pet owners are deciding to travel throughout Europe with their pets each year by taking advantage of arrangements offered by the European

traced back to its original database and the owner located.

‘Happy reunion of lost pet following ID scanning by Lancashire Police’ Pet Passport. The entry requirements for UK, Ireland and Sweden are more stringent. These schemes simplify pet travel. Specific identification of the pet by microchip is essential to verify the Passport. It is important that the animal is scanned before implantation to ensure it has not already been chipped. Regular scanning will demonstrate that the chip is still functioning and is in the correct place. All microchips now used in pets in Europe should be of the ISO FDXB type. However, dual readers that will also recognise the original FECAVA FDXA type should be used to avoid missing those dogs that were identified in the earlier years. In the UK the process of preparing animals for PETs is fairly simple and straight forward but does require advanced planning of at least 7 months. Pets need to be micro chipped, and then vaccinated against Rabies.. Four weeks after the vaccination is given a blood test must be taken to confirm the vaccine has been effective. Provided this test is positive the pet can travel but cannot re-enter the UK until 6 months after the date the blood was taken that led to the positive test. It is this time scale owners often fall foul of in their preparation timing. Owners must take some responsibility to ensure that both the chip and paperwork are in order before they travel. They should always ensure their details on the relevant database are accurate and up to date and if necessary they should record their travel address with database. Europetnet offers an internet communication between the various different European databases such that a dog lost in foreign country can be

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It really works! Recently a European microchip supplier in the UK took a phone call from a kennel facility in the Czech Republic quoting a microchip number for a dog they had taking into their care. The chip was registered a UK address and corresponded to the details held relating the dog found. Fortunately there was a mobile phone number recorded which meant the owners could be contacted. The owners were on a campervan holiday and had left the dog in the campervan to go shopping. They were totally unaware the dog had escaped the van and were amazed to have a telephone call reporting their pet had been found! Fortunately dog and owners were quickly re-united’. The Police, in Lancashire UK, recently ran a campaign to check the identity of the animals taking part in a major pet event. ’Literally hundreds of Horses and Dogs were scanned. A proportion of them contained chips which checked out as ’all in order’, but on day two of the Police Operation two stolen Spaniels were identified , recovered and reunited with their real owners. The police officer involved said: ’In over 17 years of Police service I can state that, to return the animal to its owners after six months as a ’stolen’ dog was one of the most satisfying moments in my service’ The owners were ’over the moon’. They had advertised in the local press and spent a lot of money and effort attempting to trace their animal without any success. The happy events of the weekend were only possible due to the chip id system’.

A need for special care When a microchip is implanted it is important that it is placed accurately (and not in the loose skin of the scruff of the neck which leads to migration and retention problems). There are two preferred positions which should always be checked when scanning, viz. between the scapulae in the midline and the left hand side of the neck. The animal should be scanned before implant and the chip should be checked before and after the insertion. The site should also be checked after chipping to ensure the chip is in properly under the skin and not in the coat or implant hole. These problems occur very rarely these days since accurate techniques have been encouraged, but they need to be checked when so much is relying on the microchip during travel.

EJCAP - Vol. 16 - Issue 1 - April 2006

FECAVA NEWS Chip manufactures sometimes receive phone calls from veterinarians stating that the number they have just scanned is different from the one they just implanted. Further investigation reveals that the animal was not scanned prior to being chipped and had already been implanted on a previous occasion. Obviously there is then a need to discover whether the animal has been previously registered and possibly lost or even stolen.

Feline panleukopenia: the killer disease ABCD experts recommend threeyearly boosters -Haarlem, 13 July 2006 A minimum interval of three years for booster vaccinations is normally sufficient to control Feline Panleukopenia, according to new Guidelines published today by the European Advisory Board on Cat Diseases (ABCD), providing initial vaccinations are given according to the recommended protocol. Feline Panleukopenia has been notorious for wiping out local cat populations and has therefore occasionally been referred to as ’the Cat Plague’. Mortality rates from this highly contagious parvovirus in susceptible cats are high and can exceed 90% in kittens. Indoor cats also at risk ’Indirect contact is the most common way for a cat to become infected, therefore indoor cats are at risk, too,’ according to Professor Uwe Truyen (Leipzig, Germany), ABCD member and internationally recognised specialist on parvoviruses. ’Feline Panleukopenia virus can survive in the environment for several months or even a year, as it is highly resistant, which means

that cats don’t need to meet other cats to become infected.’

Recommended Vaccination Protocol The ABCD’s recommended vaccination protocol for feline panleukopeniaconsists of two kitten injections at nine and 12 weeks of age, followed by a first booster one year later. If this basic programme is carried out correctly, subsequent booster vaccinations can normally be given at intervals of a minimum of three years. However, the ABCD stresses that maternally derived antibodies (MDAs) against feline panleukopenia virus may persist for longer than previously believed and may neutralise the vaccinal antigen, thereby preventing active immunisation. In particular, kittens from environments with a high infection pressure, such as cat shelters, or from queens that have been vaccinated regularly, for example in breeding catteries, may still have MDAs at 16 or even 20 weeks of age. In these situations, a third vaccination at four months is recommended. In adult cats with an unknown vaccination history, a single injection followed by a booster after one year is sufficient. Thereafter, boosters may be given at intervals of three years or longer. Herd immunity too low ’Thanks to efficient vaccines, we rarely see the disease today. But the virus is still lurking out there and could – and does – occasionally pop up unexpectedly,’ Professor Marian Horzinek (Utrecht, NL), ABCD chairman, added. ’In order to keep the disease at bay, the vaccinated percentage of any cat population should be as high as possible – certainly higher than the estimated 30% it is today.’

Apart from supportive treatment (fluids, antibiotics and possibly antisera or antivirals) there is no ’cure’ for the disease, and cats may die in spite of intensive veterinary care. However, vaccines currently on the market are highly effective and efficiently protect cats against the disease, providing they are given according to the recommended protocol. For further details and downloads of the full-text ABCD Feline Panleukopenia Guidelines, please visit www.abcdvets.org. These guidelines also give recommendations for specific situations, such as immunocompromised cats, breeding catteries and cats undergoing corticosteroid treatment. The guidelines on feline panleukopenia were adopted at the third meeting of the ABCD, held in Haarlem (NL) on 8-9 June 2006. At the meeting, the panel also discussed feline herpesvirus disease, for which guidelines are currently in preparation.

Turkey gears up to adapt to EU Veterinary Regulations EU Veterinary platform founded The EU Veterinarian Platform is a civilian initiative that was established for providing studies related to formation of information share, communication, discussions and brain storming, healthy, proper and quick adaptation process for supplementing contributions to Veterinarian profession within the European Union adaptation process. website: www.abveteriner.org

WSAVA Activities

From Dr Walt Ingwersen WSAVA Editor WSAVA Standards for Histological and Clinical Diagnosis of Canine and Feline Liver Diseases WSAVA’s first textbook is on the shelves! In a publishing partnership with Elsevier, WSAVA is proud to announce the availability of its first scientific textbook, entitled WSAVA Standards

for Histological and Clinical Diagnosis of Canine and Feline Liver Diseases, representing a culmination of efforts begun in 2000 and prompted by discussions between the then WSAVA president Hans-Klaus Dreier, presidentelect Claudio Brovida, and Dr. Jan Rothuizen of Utrecht University. Born from a WSAVA strategic initiative to strengthen the relationship between veterinary academia and veterinary medical associations, this project is

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the first in a series of standardization initiatives begun by the WSAVA in an effort to provide clear direction in areas of academic research that have a direct impact on the practice of veterinary medicine (for a historical overview of the WSAVA standardization efforts, refer to the October 2005 Monthly News on the WSAVA website www.wsava.org). The authors involved are a veritable ‘who’s who’ of prominent, international researchers in veterinary hepatology

EJCAP - Vol. 16 - Issue 2 October 2006 and also includes one eminent human liver researcher. The list of authors include: – Jan Rothuizen DVM, PhD, Dip ECVIM-CA; Utrecht University – Susan Bunch DVM, PhD, Dip ACVIM – Jenny A. Charles, DVM, PhD – John Cullen VMD, PhD; North Carolina State University – Valeer Desmet MD, PhD; Leuven University – Viktor Szatmari DVM, PhD; Utrecht University – David Twedt DVM, Dip ACVIM; Colorado State University – Ted van den Ingh DVM, PhD, Dip ACVP; University of Pennsylvania – Tom van Winkle VMD, Dip ACVP; University of Pennsylvania – Robert Washabau VMD, PhD, Dip ACVIM; University of Minnesota The textbook is designed to provide a world standard of guidelines for the diagnosis of liver diseases in dogs and cats using both histological and clinical criteria. Chapters include:

– Sampling and handling of liver tissue – Ultrasonographic identification and characterization of congenital portosystemic shunts and portal hypertensive disorders – Morphological classification of biliary disorders – Morphological classification of parenchymal disorders, including – Normal histology, reversible hepatocyte injury, and hepatic amyloidosis

– Hepatocellular death, hepatitis, and cirrhosis – Hepatic abscesses and granulomas, hepatic metabolic storage diseases, and miscellaneous conditions – Morphological classification of neoplastic disorders This consolidation of international science and opinion regarding the diagnosis and staging of canine and feline liver disorders represents a critical step in elevating both the level of care provided by the veterinary profession for pet’s suffering from liver disorders as well as ensuring that the common language proposed facilitates a greater degree of communication between researchers and ultimately, our understanding of these ailments. For additional information and to order the book, visit the Elsevier website at www.elsevier.ca/product.jsp?isbn= 070202791X The WSAVA would like to recognize and thank Hill’s Pet Nutrition for their generous sponsorship which made this work possible.

UEVP NEWS

From Marc Buchet, Past President FECAVA, UEVP Treasurer European Acknowledged Veterinarian In November 2005, during the General Assembly Meeting, UEVP adopted a policy paper concerning European Acknowledged Veterinarians The acknowledgment of a veterinarian should be: 1 Based on a species (or a group of species) orientation - such as for cattle, companion animals, equines, pigs, poultry etc;. 2 Preceded by a period of species related, theoretical and practical training together with a suitable level of professional experience; 3 Issued by a national competent authority (such as Chamber, Statutory Body, Veterinary Organisation, Ministry, Veterinary Faculty, Scientific Organisation etc); 4 Supervised by a competent European Authority in order that the acknowledgement be recognised as a ‘European’ ; 5 Regular revalidation.

Several countries already have some post-graduate qualifications and UEVP thinks that it would be better to define a ‘European level’ as soon as possible in order to obtain mutual recognition instead of harmonizing later different existing systems. The notion of ‘Acknowleged’ Vet will influence positively the veterinary profession and fulfil consumer (with regard to the need for clear information) and stakeholders requirements (e.g. insurance companies, retailers...). This system of is totally different from the EBVS specialisation which is mainly discipline-orientated and where qualification and expertise are at a higher level . Practical experience for recognition as an acknowledged veterinarian will only be possible after working for three years within the last 5 years spending at least 50% of the time with the species concerned, based on a working week of ± 40 hours. In addition, during this period the applicant should have obtained in average 35 CPD scientific attendance

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hours a year relevant to the species concerned. Each country would have to evaluate the level of abilities and skills of the candidate before acknowledgment. This should be either by a certificate issued by the supervising competent veterinary surgeons with whom he/she worked for a certain time or after being examined by a professional body (or both). In order to maintain the acknowledgement veterinarians should obtain at least 175 hours of CPD scientific attendance hours over 5 years. The veterinarian also has to continue to work at least 50% of his/her work time within the field acknowledged. Revalidation should be done at least every 5 years. UEVP hopes that the principle of ‘Acknowledged Vet’ will be supported by each National Association and by specialised groups such as FECAVA and FEEVA.

EAR, NOSE AND THROAT FECAVA SPONSORED PAPER

Inner ear dysfunction related to ear disease in dogs and cats G. ter Haar(1)

SUMMARY Inner ear disease can be either primary, with dysfunction of the cochlea or the vestibulum or both, as a result of pathology of the inner ear itself; or secondary as a result of extension of disease from surrounding structures, usually the middle ear. Inner ear dysfunction is usually demonstrated as peripheral vestibular ataxia, but hearing loss is present with many diseases as well, although more difficult to detect. The clinical examination, neurological and otoscopic examination findings and diagnostic work-up with radiography or CT-scan/MRI and brainstemevoked response audiometry of patients with primary or secondary inner ear disorders are discussed. In addition, the aetio-pathogenesis and medical or surgical therapy of those ear diseases that can result in hearing loss or peripheral vestibular ataxia are reviewed. These include chronic otitis externa, feline inflammatory polyps, aural neoplasia, chronic otitis media and interna, ototoxicity, congenital deafness, age-related hearing loss, geriatric canine and idiopathic feline vestibular disease and congenital vestibular syndromes. Surgical procedures discussed include removal of inflammatory polyps via lateral incision in the vertical ear canal, total ear canal ablation, and lateral and ventral tympanic bulla osteotomy.

inner ear dysfunction however, for outer ear canal, middle ear, brainstem and central nervous system pathology can affect hearing as well. Conductive deafness results from a lack of presentation of sound to the inner ear, usually secondary to otitis externa or media, while sensorineural deafness occurs with abnormalities of the cochlear system, cranial nerve VIII or auditory pathways and higher brain centres. The most common forms of sensorineural deafness are congenital deafness, deafness as a result of ototoxicity and presbycusis or age-related hearing loss. Usually, loss of balance is the result of disorders of the peripheral vestibular system (the inner ear receptors and/or the vestibular part of the eighth nerve), but central vestibular disease (the brainstem vestibular nuclei in the medulla oblongata and neurons in the flocculonodular lobe of the cerebellum) has to be ruled out. This article describes the diagnostic work-up of patients with primary or secondary inner ear disorders and the technique of brainstem-evoked response audiometry in particular. In addition, the aetio-pathogenesis and medical and/or surgical therapy of those ear diseases that can result in hearing loss and/ or peripheral vestibular ataxia are discussed.

This paper is based in part on a lecture given at the ESAVA Congress* in Tallinn

Introduction The inner ear lies safely protected within the osseous labyrinth of the petrous part of the temporal bone. The membranous labyrinth consists of three parts: the cochlea, responsible for hearing, and the vestibule and the semicircular canals responsible for maintaining balance. Inner ear disease can be either primary with dysfunction of the cochlea or the vestibulum or both as a result of pathology of these end-organs (e.g. ototoxicity and age-related hearing loss) or secondary as a result of extension of disease from surrounding structures (e.g. otitis media). Inner ear dysfunction is usually demonstrated as peripheral vestibular ataxia (head tilt, horizontal nystagmus, circling or falling toward the side of the lesion) as hearing loss usually goes unnoticed until complete deafness is recognized. Hearing loss doesn’t necessarily reflect primary or secondary

(1) Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, PO Box 80154, NL-3508 TD Utrecht. E-mail: [email protected] *Sponsored by FECAVA, Tallinn, May 13-14, 2006.

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Fig. 1. Transverse CT image of a 1-year-old cat presented with left sided peripheral vestibular ataxia as a result of inflammatory polyp associated otitis media and interna.

Fig. 2. Representative sample of a brainstem auditory evoked response after an 80 dB SPL click stimulus.

Clinical examination in dogs and cats with inner ear dysfunction

fluid cannot be differentiated from tissue (polyp, neoplasia) and absence of radiographic changes does not rule out otitis media. Advanced imaging with CT or MRI is necessary in most cases for proper evaluation of the middle ear and inner ear to some extent (see Fig. 1). CT is considered superior to MRI for bony changes, whereas MRI is better for detection of soft tissue abnormalities [3]. With these two techniques morphological abnormalities of the petrous bone and inner ear structures can be recognized, but functional abnormalities can only be diagnosed with electrophysiological methods like brainstem-evoked response audiometry.

When confronted with an animal with either vestibular ataxia or hearing loss, a complete history has to be taken and thorough physical, neurological, and otoscopic examinations have to be performed. In most cases, the differentiation between central and peripheral vestibular disease and between conductive and sensorineural hearing loss can be made without additional examination. The presence of a spontaneous vertical nystagmus, cranial nerve deficits other than facial nerve paralysis and proprioceptive abnormalities always indicate a central vestibular lesion, whereas peripheral vestibular ataxia usually is accompanied by horizontal nystagmus and is sometimes associated with a history of topical ear medication or clinical signs of otitis externa or media [1]. Much information can be obtained with otoscopy which usually can be performed in the awake animal even when ear flushing is necessary for complete visualization of the tympanic membrane. However, before flushing, material should be obtained from the horizontal part of the ear canal for cytological examination, culture and in some patients susceptibility testing. After flushing, masses can easily be identified and samples can be taken for histopathology. Bulging, increased opacity and hyperaemia of the tympanic membrane may be present with otitis media. A myringotomy can be performed in dogs with an intact tympanic membrane to obtain samples for culture and susceptibility testing and cytological examination. When significant abnormalities are detected on otoscopy, the diagnosis of peripheral vestibular disease and the presence of at least some degree of conductive hearing loss can safely be made. In absence of abnormalities, peripheral vestibular disease cannot be excluded. Radiographs of the bullae may then be useful to further differentiate between diseases, although they are not very sensitive [2, 3]; ventrodorsal, lateral oblique and open-mouth views are most helpful. Anaesthesia is necessary for proper positioning. Abnormalities of the bulla indicating disease include increased opacity, sclerosis and lysis. However,

Hearing assessment using brainstemevoked response audiometry (BERA) Several methods have been employed to test hearing ability in dogs, ranging from behavioural studies to measurement of electrical responses after auditory stimulation, using impedance audiometry (tympanometry, acoustic reflex testing), evoked response audiometry (brainstem (BERA) and middle latency (MLAER) auditory evoked responses), and cochlear microphony [4,5]. Of these techniques, brainstem-evoked response audiometry is used most often in veterinary medicine. The brain responds to auditory stimuli by consistent changes in electrical activity; once the nerve impulse is generated in the cochlea, the signal travels along the acoustic nerve to the cochlear nuclei in the brainstem. From here, many projections lead to other nuclei in the brainstem and ultimately to the primary auditory cortex. These changes can be recorded from scalp electrodes [4]. The time between stimulation of the ear and electrophysiological response is called latency. For the early latency components, meaning the responses recorded between 0 and 10 milliseconds after the stimulus, generators are thought to arise almost totally within the brainstem. Therefore, this series of waves is referred to as the brainstem auditory evoked responses. Responses after 10 milliseconds are called middle latency responses, generators of these potentials are thought to be nuclei in the thalamus and areas of the auditory cortex [5].

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EJCAP - Vol. 16 - Issue 2 October 2006 factors [6]. Since chronic infections may result in stenosis or occlusion of the ear canal and blockage of sound transmission or may lead to chronic otitis media and/or interna, otitis externa has to be treated appropriately without delay to prevent inner ear dysfunction. Primary factors directly cause otitis externa and include parasites (ear mite; otodectes cynotis), foreign bodies, inflammatory polyps, tumours, hypersensitivities (atopy, food hypersensitivity), endocrine abnormalities (hypothyroidism) and keratinisation disorders [6]. Predisposing causes of otitis externa make the ear canal more susceptible to inflammation and secondary infection. These factors include anatomical conformation (pendulous ears, narrow ear canals and excessive hair growth) and changes in the external environment of the ear canal (excessive moisture, excessive ear cleaning or trauma from cotton swabs). Perpetuating factors exacerbate and maintain the disease even after the primary factors are eliminated and include secondary bacterial and/or yeast infection, otitis media and inappropriate treatment [2, 6]. In most cases of chronic otitis externa, primary factors, predisposing and/or perpetuating factors can and should be identified and treated. In chronic cases, elimination of underlying factors however, usually doesn’t end the inflammatory process [2]. Management should then be aimed at thoroughly cleaning and drying the ear canal and administering appropriate topical therapy for a longer period of time, sometimes even a lifelong treatment is necessary. Ointments with broad-spectrum antibiotics and corticosteroids should be used with careful attention to complete filling of the entire ear canal and tapering off the frequency of treatment based on clinical effect and control otoscopy. Total ear canal ablation is reserved for unresponsive or proliferative chronic otitis externa, when the relief of chronic pain and discomfort outweighs the disadvantage of the hearing loss that will result after surgery (see Fig. 3). Hearing function was measured in dogs with otitis externa using brainstem evoked response audiometry. It was concluded that most dogs with chronic otitis externa have some form of conductive hearing loss with severe loss in dogs with severe otitis. Cleaning the ear canal produced measurable improvements in hearing in several dogs, indicating the profound effect of physical obstruction of the external ear canal by debris [7].

In the last two decades, brainstem auditory evoked responses have been used increasingly to test hearing ability in veterinary medicine. The acoustic signal usually consisted of a click stimulus, which stimulates a large part of the cochlea, since it consists of a wide spectrum of frequencies (many different tones). Brainstem evoked response audiometry using clicks will suffice for differentiating sensorineural from conduction deafness and is of use in assessing some brainstem pathologic changes. Frequency-specific information, however, is needed in assessing the extent of neurological deafness, e.g. noise-induced deafness, deafness caused by ototoxicity and presbycusis, which can all be partial and frequency-specific (hearing loss limited to small areas of the cochlea, for instance the high frequency area) [4]. In our laboratory a method was developed to deliver tone bursts ranging in frequency from 1 - 32 kHz for frequency-specific assessment of the canine cochlea. Brainstem auditory evoked responses to a click (CS) and to 1, 2, 4, 8, 12, 16, 24, and 32 kHz tone burst stimulations (TS) were compared at 80 dB sound pressure level stimulus intensity in 10 clinically-healthy dogs, 3.5 to 7.0 years of age. The responses were obtained with the animals under a light plane of anaesthesia. All stimulations yielded a 5-7 positive wave pattern, with the exception of the 1 kHz TS, which evoked a frequency-following response (see Fig. 2). There were marked differences in the thresholds for different stimulations, the lowest being for the click and for 12 and 16 kHz toneburst stimulations. The thresholds for all other toneburst stimulations were significantly higher than for the click stimulation. Our report demonstrates that hearing was best in the high-frequency area in our dogs, with an optimum between 12-14 kHz (see fig. 14) and provides a normative database for parameters necessary to evaluate the frequency-specific hearing losses in dogs [4].

Otitis externa Otitis externa is common in dogs and cats and has numerous causes, usually classified as primary, predisposing or perpetuating Fig. 3. Chronic proliferative otitis externa in a French Bulldog.

Inflammatory polyps Nasopharyngeal polyps, also called otopharyngeal or inflammatory polyps are benign pedunculated growths of uncertain origin but thought to arise as a result of chronic inflammation [8, 9]. Polyps have been associated with rhinitis and otitis resulting from various bacterial and viral agents, a congenital origin has been suggested as well. They may originate from the mucosal lining of the middle ear, auditory tube and nasopharynx, all of which are similar histologically. Otopharyngeal polyps occur in cats of any age, although most animals are less than 2 years of age. Polyps in the external or middle ear mimic signs of otitis externa, otitis media or otitis interna [8, 9]. Otoscopy after flushing may reveal a visible pink or grey smooth, spherical mass occluding the canal (see Fig. 4). Cytological or histological examination of biopsies will reveal the nature of the tissue when diagnosis is not straightforward. Some surgeons perform a ventral bulla osteotomy but recurrence is uncommon

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Fig. 4. Video-otoscopic view of a feline inflammatory polyp in the external ear canal, visible after flushing.

Fig. 5. Removal of feline inflammatory polyp via lateral incision in vertical ear canal.

with simple traction-avulsion after an incision in the vertical ear canal [2]. After aseptic preparation of the surgical site, an incision is made in the skin in a dorsoventral direction over the palpable vertical part of the ear canal. The subcutaneous tissue and parotid gland are dissected with small scissors to free the cartilage of the vertical ear canal, which is opened with a vertical stab incision. Stay sutures are placed on both sides of the incision in the ear canal cartilage to increase visualisation and avoid damage to the cartilage. A small closed haemostatic forceps is then introduced into the ear canal, meticulously following the direction of the horizontal ear canal until the polyp is encountered. This forceps is then opened and advanced deeper over the polyp until it can be grasped as close as possible to the osseous meatus. The forceps is then gently rotated and traction is applied until the polyp is removed (see Fig. 5). The middle ear cavity is flushed with warm saline and with a small curette the osseous meatus and most lateral aspect of the tympanic cavity is “palpated” to check for additional inflammatory tissue which is removed with this curette when encountered. The stay sutures are removed and the cartilage of the ear canal is closed with 4-0 monofilament suture material in an interrupted pattern. The subcutis is closed in a continuous pattern with 4-0 absorbable monofilament suture material and the skin is closed in a subdermal suture pattern using the same suture material. To date, there are no reports on pre-operative and postoperative hearing assessments using brainstem-evoked response audiometry in cats with polyps. It is very likely however that preoperatively a severe form of conductive hearing loss is present. Since polyps are usually recognized after a history of chronic otitis externa, media or interna, some form of sensorineural hearing loss will be present in addition. The improvement in hearing ability after surgery is therefore unknown and unpredictable at the moment.

Aural neoplasia Ear tumours occur in older cats (mean age of 7 and 11 years for benign and malignant tumours, respectively) and dogs (9 and 10 years of age) [10, 11]. The most frequently observed clinical signs are those of a unilateral otitis externa with otic discharge, odour, pruritis, local pain and a mass on otoscopy. Neurological signs are observed in approximately 10% of dogs with malignant tumours and 25% of cats with either benign polyps or malignant tumours [10, 11]. Since approximately 25% of malignant forms will have evidence of bulla involvement, skull radiographs or computed tomography are recommended as part of the diagnostic work-up. Benign tumours are papillomas, basal cell tumours and ceruminous gland adenomas, especially found in dogs, and ceruminous gland cysts usually found in cats. Malignant tumours include ceruminous gland adenocarcinoma (CGC, dog and cat); squamous cell carcinoma (SCC, dog and cat) and carcinoma of unknown origin (dog). Most benign ear canal tumours in dogs and cats can be readily managed with conservative surgical resection. But aggressive excision, including total ear canal ablation and lateral bulla osteotomy, should be the treatment of choice for malignant ear canal tumours in both species. A good prognosis with a high likelihood of long-term survival results from such a procedure in the dog [10]. A fair prognosis in the cat can be expected for CGC, and a guarded prognosis for SCC or carcinoma of undetermined origin [10]. Primary neoplasia of the bullae or bony labyrinth or neurofibrosarcoma of the peripheral nerve (N VIII) are very rare but should be included in the differential diagnosis of inner ear dysfunction [2,8]. Local spread from tumours within the ear canal is probably more common. Facial nerve paralysis or Horner’s syndrome is common when tumours are located in the middle and inner ear. These tumours can usually be demonstrated with CT-scan or MRI. Diagnosis can be confirmed

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Fig. 6. TECA: The ear canal is freed from the auricular cartilage with strong scissors.

Fig. 7. TECA: The cartilaginous part of the ear canal is removed from the osseous canal with scissors.

by biopsy findings. Because of the invasive nature of most of these tumours, total resection is difficult but radiotherapy or chemotherapy may be beneficial in some animals [8].

Indications for TECA are chronic unresponsive or proliferative otitis externa or neoplasia of the ear canal. A V-shaped incision is made in the skin from the intertragic incisure to the ventral limit of the vertical ear canal and from the tragohelicine incisure to the same ventral point [2]. The skin flap is retracted dorsally and the lateral aspect of the vertical ear canal is exposed. The cartilage and the skin of the medial wall of the ear canal are

separated from the cartilage and the skin on the inner side of the base of the pinna by use of strong scissors (see Fig. 6). The vertical ear canal is now dissected to the level of the horizontal ear canal with appropriate care taken to avoid the facial nerve in this area. The dissection is continued with freeing the horizontal part of the ear canal from the surrounding tissues to the level of the external acoustic meatus. The ear canal is then removed with scissors and removal of all of the skin lining the osseous external ear canal is accomplished with a small curette (see Fig. 7). When this is performed correctly, no lateral bulla osteotomy is necessary in absence of chronic otitis media. With chronic otitis media or para-aural abscessation and accumulation of inflammatory tissue or thick exudate in the middle ear cavity, a

Fig. 8. LBO: The ventral and lateral wall of the bulla are removed with rongeurs until visualization of the bulla is adequate.

Fig. 9. TECA: The pinna is remodelled, a Penrose drain is placed and subcutis and skin are closed routinely.

Total ear canal ablation (TECA)

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Fig. 10. VBO: The opening in the ventral bulla can be enlarged with rongeurs.

Fig. 11. VBO: All abnormal tissue should be removed from the bulla with gentle curettage.

lateral bulla osteotomy (LBO) is performed from this point on. After total ear canal ablation, the tissues from the lateral aspect of the bulla are bluntly dissected as close to the bone as possible and the lateral and ventral aspect of the bulla are removed with rongeurs until adequate visualization of the middle ear cavity is possible (see Fig. 8). Samples can be obtained for culture and susceptibility testing and for cytology or histopathology. After curettage the tympanic cavity is copiously lavaged with warm saline and closure is as for total ear canal ablation. After completion of the TECA or TECA with LBO, the pinna is remodelled and sutured with absorbable suture material [2]. A penrose drain is placed and subcutaneous tissue and skin under the pinna are closed in a routine manner (see Fig. 9). Complications after TECA are facial nerve paralysis, wound infection and dehiscence and chronic fistulation, but most complications can be avoided with meticulous surgical technique. Another consequence of TECA is conductive hearing loss. In one study it was determined by BERA that hearing was lost completely with TECA and LBO except when the tympanic membrane and ossicles were retained [12]. This should be avoided however to prevent accumulation of keratinized cellular debris that could result in infection or late abscessation.

with perforating foreign bodies or they occur as a sequel to chronic, usually proliferative or severe otitis externa. Bacteria can directly infect the middle and inner ear, or the bacteria can produce toxins that inflame the labyrinth. Clinical signs associated with middle ear disease can therefore vary from otalgia (otic pain), lethargy, inappetence and pain on opening of the mouth or reflect concurrent otitis externa, especially in dogs, or otitis interna. The diagnosis can be made on history, clinical signs, otoscopy and diagnostic imaging as discussed before. The therapy of otitis media and/or interna consists of systemically delivered broad-spectrum antibiotics [2]. Amoxicillin potentiated with clavulonic acid or enrofloxacin are first choice antibiotics. Perforated tympanic membranes should close in 4 weeks, when the infection is cured. No ototoxic topical medications should be used when the tympanic membrane is not intact to avoid ototoxicity. When the tympanic membrane is intact, but bulging, a myringotomy could be performed under general anaesthesia. When the tympanic membrane is intact, a concurrent otitis externa can be treated with topical ointments containing antibiotics and corticosteroids. Chronic unresponsive or recurrent otitis media warrants surgical intervention. Total ear canal ablation with lateral bulla osteotomy should be considered in cases with severe secondary changes of the external ear canal and concurrent otitis media. If the external ear canal is not affected, a ventral bulla osteotomy may be performed to remove gross exudates and establish drainage from the middle ear. Damage to the tympanic membrane has been shown to cause conductive hearing impairment. Dogs with perforated tympanic membranes had significantly elevated hearing thresholds assessed by BAER testing, but values returned to baseline by 3 to 4 weeks [1]. In a study on the effects of ventral tympanic bulla osteotomy, brain stem auditory evoked potentials were measured using an air-conducted sound stimulus before and after surgery and before killing. Even though nine out of 12 dogs had proliferation of subperiosteal new bone from the inner surface of the tympanic bulla with some obliteration of the bulla, the measured BERA sensitivity before killing was equivalent to preoperative levels in 11 dogs [14].

Otitis media and interna Bacterial otitis media in dogs generally develops as an extension of otitis externa through a perforated tympanum, but pharyngeal infections may, in rare instances, extend to the middle ear through the auditory tube [13]. Cats may develop otitis media through this route as a sequel to upper respiratory tract disease. Involvement of the middle ear through haematogenous spread is only rarely encountered [13]. Other causes of otitis media include fungal infections (Aspergillus, Candida), neoplasia, inflammatory polyps, trauma and primary tumours. Organisms cultured most frequently from affected middle ears include Pseudomonas species, Staphylococcus intermedius, beta-haemolytic streptococcus, Malassezia, Corynebacterium species, Enterococcus species, Proteus species, E. Coli and anaerobes. Infections with these agents are usually associated

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Fig. 13. VBO: After placement of a Penrose drain, closure is routine.

Fig. 12. VBO: In cats, the dorsolateral compartment should be opened separately.

Ventral bulla osteotomy (VBO)

for ear surgery, should not be underestimated however [16]. In order for a drug to exert ototoxicity, it must reach the inner ear. This may be the result of haematogenous spread following oral or parenteral dosage. Commonly however, ototoxicity follows topical application of ototoxic agents into the external ear canal and their subsequent passage into the middle ear via a ruptured tympanum. Subsequent diffusion into the middle ear is enhanced by the presence of otitis media, which induces increased permeability through the round window membrane. The agent passes through the membrane of the round window and enters the perilymph in the tunnel of Corti. It thereby comes in contact with the hair cells of the organ of Corti and causes degeneration of the perceptive cells. This route of entry was demonstrated for gentamicin in the guinea pig, but similar structures in the vestibule make it likely that perilymph also reaches the sensory cells of the vestibular labyrinth [17]. Clinical signs of vestibular damage may be reflected very early (as soon as 10 minutes!) after the insult has been effected. Within three days central compensation results in diminishing and eventually disappearance of the nystagmus, gradual attempts to stand, and beginning efforts to eat and drink, but the head tilt is unchanged. Within three weeks the situation improves, but jumping and walking down stairs often still results in falling. The compensation is optimal after about three months [2]. The head tilt however may still be obvious and permanent. There is no such compensatory mechanism for cochlear hair loss, hence deafness as a result of ototoxicity is permanent. In general, ototoxic effects are dose related, therefore avoiding ototoxic chemicals or reducing the dose and frequency of administration is important [15]. Careful observation and regular follow-up examinations of the patient may allow detection of vestibular signs early enough to allow the clinician to suspend therapy. It is difficult to detect early cochlear damage without sophisticated investigatory tools, such as BAER, however. Much research has been focused on medically preventing ototoxicity as a result of cisplatin in human medicine. Some success has been achieved by co-treatment with protective agents. Nearly all these agents are sulphur- or sulfhydryl-containing compounds (thio compounds), known as antioxidants and potent heavy

An incision is made parallel with the midline, centred 2-3 cm toward the affected side from halfway the mandible to the level of the atlas, following the medial border of the rostral digastric muscle [2]. The platysma muscle is incised and linguofacial vein is retracted. Care should be taken to avoid damage to the nerves of the pharyngeal plexus. The incision is deepened by blunt dissection between digastricus muscle and hypoglossal and styloglossal muscles until the bulla can be palpated. A Steinmann pin can be used to make a hole on the ventral aspect, the opening can then be enlarged with a small rongeur (see Fig. 10). The opening should be large enough to allow for gentle curettage of the entire ventral compartment (see Fig. 11). In cats the dorsolateral compartment should be opened after this using the same technique (see Fig. 12). All abnormal material should be removed and collected for culture, sensitivity testing, cytology and histopathology, but curettage should be very careful to avoid damaging the round and oval windows. The cavity is flushed and drained with a penrose drain, after which closure is routine (see Fig. 13). Aftercare consists of broad-spectrum antibiotics for 14-21 days depending on severity of middle ear infection and analgesics for 3-4 days.

Ototoxicity Over 180 compounds and classes of compounds have been identified as ototoxic. Not all of them are equally toxic and some effects are reversible, but in most instances the deficit is permanent. In human medicine, the aminoglycoside antibiotics, the antineoplastic drugs cisplatin and carboplatin, loop diuretics, salicylates, quinine, deferoxamine, and various toxic substances are recognized for their propensity to cause ototoxicity [15]. The best recognized, and perhaps most frequent, agents of ototoxicity in veterinary medicine are the amino glycoside antibiotics, especially gentamicin, but polypeptides, chloramphenicol, erythromycin, and (oxy)tetracycline are ototoxic as well. The importance of disinfectant-based (clioquinol, chlorhexidine, cetrimide, iodine, povidone-iodine and 70% ethanol) ototoxicity, for instance used

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Inner ear dysfunction related to ear disease in dogs and cats - G. ter Haar

Frequency (Herz) Fig. 14. Hearing thresholds are significantly increased in old dogs compared to the middle-aged group, especially in the high frequency area.

metal chelators. Currently, the otoprotective action of the ACTHrelated neuropeptides is under investigation since preliminary results suggest that it may be possible to stimulate recovery from acute hearing loss using these neuropeptides [18].

in affected breeds [20]. Until these markers are found, BERA testing will be the sole method for identifying affected dogs and cats. Both unilaterally and bilaterally affected animals should be excluded from breeding.

Congenital deafness in dogs and cats

Age related hearing loss

In most dog and cat breeds inherited congenital sensorineural deafness results from perinatal degeneration of the stria vascularis which leads to collapse of Reissner´s membrane and the cochlear duct and to hair cell degeneration [1,19]. The strial degeneration appears to result from absence of melanocytes and begins as early as 1 day after birth, but is only clearly evident histologically by 4 weeks. This disease is common in many breeds of dogs and cats with a predilection for white coat colours and a strong association of deafness with blue irises. Deafness is most closely linked to the recessive alleles of the pigmentation locus S, responsible for Irish spotting, piebald spotting or extreme-white piebald spotting. The most commonly affected breeds include Dalmatians, English Setters, Australian Shepherds, Border Collies, and Shetland Sheepdogs, but there are over 80 breeds reported [20]. In the Dobermann, and probably other dog breeds not carrying the merle or piebald pigment genes, the deafness results from direct loss of cochlear hair cells without any antecedent effects on the stria vascularis [19]. The percentage of affected dogs with unilateral deafness ranged from 73% to 90% in one report [20]. Unilaterally deaf dogs usually exhibit no clinical signs and without BERA testing (as puppies or prior to breeding) these dogs continue to increase the prevalence of the disorder. Currently, investigations focus on finding genetic markers for the gene or genes responsible for pigment-associated deafness to reduce the prevalence

Presbycusis is a form of hearing loss associated with ageing and the most common form of sensorineural hearing loss in humans. The precise mechanisms by which aging results in presbycusis is not known, but noise, hereditary, and systemic degenerative changes appear to contribute to its development in humans [21]. Although a similar disease condition most certainly exists in dogs and probably also in cats, there are not many reports describing the brainstem-evoked response audiometric changes in old dogs and the correlation with histopathological changes. To evaluate hearing in old dogs, animals older than 12 years of age were examined in our laboratory with brainstem-evoked response audiometry using the same method as mentioned before. The results showed that their hearing range did not differ much from the first group, but their thresholds were significantly higher, especially in the high-frequency area (see Fig.14). The histology of the cochlear changes was studied and preliminary results show profound hair cell loss and neuronal loss, most prominent in the basal coils of the cochlea, comparable to presbycusis in humans. There is no cure for sensorineural hearing loss, but ongoing research in human and veterinary medicine regarding middle ear implants, cochlear implants, neurotrophic factors and stem cell research is yielding promising results.

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Geriatric canine and idiopathic feline vestibular disease

[7]

[8]

Geriatric canine vestibular disease is the most common cause of unilateral peripheral vestibular disease in old dogs [22]. The cause is still unknown. The mean age of onset is 12.5 years, and the disorder is characterized by the very sudden onset of unilateral peripheral vestibular signs. No other neurological abnormalities, like facial nerve paralysis or Horner’s syndrome are observed. The diagnosis is made on exclusion of other causes and on the alleviation of clinical signs with time. The prognosis for recovery is excellent. Occasionally vomiting is severe, and Hi histaminergic receptor antagonists, M1 cholinergic receptor antagonists or vestibulosedative drugs are administered for 2-3 days to alleviate the emesis associated with motion sickness [22]. Feline idiopathic vestibular syndrome is an acute, nonprogressive disorder similar to the previous syndrome in dogs and affects cats of any age, particularly in the summer months [23]. This disease is characterized by the peracute onset of peripheral vestibular signs with no abnormalities of proprioception or in other cranial nerves. The diagnosis is based on the clinical signs and the absence of ear problems or other disease. The prognosis is excellent; spontaneous improvement is usually seen within 2-3 days, with a complete return to normal within 2-4 weeks [22, 23].

[9] [10]

[11] [12]

[13] [14]

[15]

[16]

Congenital vestibular syndromes

[17]

Congenital peripheral vestibular syndromes have been reported in the German Shepherd, Doberman Pinscher, Akita, English Cocker spaniel, Beagle, Smooth Fox terrier and Tibetan terrier, as well as in Siamese, Burmese and Tonkinese cats [22,23]. Peripheral vestibular signs, usually unilateral, may be present at birth or develop during the first few months of life. Head tilt, circling and ataxia may initially be severe but are non-progressive and with time, compensation is common and many affected animals make acceptable pets. The diagnosis is based on the early onset of signs, before 3 months of age [22]. Radiography and CSF analysis are normal. Deafness may accompany the vestibular signs, particularly in the Doberman Pinscher, the Akita and the Siamese cat and can be diagnosed using BERA [23].

[18]

[19] [20]

[21]

[22]

References [1] [2]

[3] [4]

[5] [6]

[23]

COOK (L.B.) - Neurological Evaluation of the Ear. Vet Clin Small Anim, 2004, 34: 425-35. VENKER-VAN HAAGEN (A.J.) - The Ear. In: Venker-van Haagen A.J., Ear, Nose, Throat, and Tracheobronchial Diseases in Dogs and Cats. Hannover: Schlütersche; 2005. BISCHOFF (M.G.) and KNELLER (S.K.) - Diagnostic Imaging of the Canine and Feline Ear. Vet Clin Small Anim, 2004, 34: 437-58. TER HAAR (G.), VENKER-VAN HAAGEN (A.J.), DE GROOT (H.N.M.) and VAN DEN BROM (W.E.) - Click and Low-, Middle-, and High-Frequency Toneburst Stimulation of the Canine Cochlea. J Vet Intern Med, 2002, 16: 274-280. SIMS (M.H.) - Electrodiagnostic evaluation of auditory function. Vet Clin North Am Small Anim Pract, 1988, 18: 913-944. ROSSER (E.J.) - Causes of otitis externa. Vet Clin Small Anim, 2004, 34: 459-68.

EGER (C.E.), LINDSAY (P.) - Effects of otitis on hearing in dogs characterised by brainstem auditory evoked response testing. J Small Anim Prac, 1997, 38(9): 380-6. FAN (T.M.), DE LORIMIER (L.) - Inflammatory polyps and aural neoplasia. Vet Clin Small Anim, 2004, 34: 489-509. MUILENBURG (R.K.), FRY (T.R.) - Feline nasopharyngeal polyps. Vet Clin Small Anim, 2002, 32: 839-49. VAIL (D.M.) and WITHROW (S.J.) - Tumors of the Skin and Subcutaneous Tissues. In Withrow SJ and MacEwen EG (ed): Small animal clinical oncology. Philadelphia, WB Saunders, 2001, pp. 252-254. KIRPENSTEIJN (J.) - Aural Neoplasms. Semin Vet Med Surg (Small Anim), 1993, 8(1): 17-23. MCANULTY (J.F.), HATTEL (A.) and HARVEY (C.E.) - Wound Healing and Brain Stem Auditory Evoked Potentials After Experimental Total Ear Canal Ablation With Lateral Tympanic Bulla Osteotomy in Dogs. Vet Surg, 1995, 24: 1-8. GOTTHELF (L.N.) - Diagnosis and Treatment of Otitis Media in Dogs and Cats. Vet Clin Small Anim, 2004, 34: 469-87. MCANULTY (J.F.), HATTEL (A.) and HARVEY (C.E.) - Wound Healing and Brain Stem Auditory Evoked Potentials After Experimental Ventral Tympanic Bulla Osteotomy in Dogs. Vet Surg, 1995, 24: 9-14. RYBAK (L.P.), KANNO (H.) - Ototoxicity. In: JJ Balenger and JB Snow, Eds; Otorhinolaryngology: Head and Neck Surgery, 15th ed., Baltimore, Williams & Wilkins, 1996, pp. 1102-1108. GALLÉ (H.G), VENKER-VAN HAAGEN (A.J.) - Ototoxicity of the antiseptic combination chlorhexidine/cetrimide (Savlon®): effects on equilibrium and hearing. Vet Quart, 1986, 8: 56-60. De GROOT (J.C.M.J.), MEEUWSEN (F.), RUIZENDAAL (W.E.), VELDMAN (J.E.) - Ultrastructural localization of gentamycin in the cochlea. Hearing Research, 1999, 50: 35-42. WOLTERS (F.L.), KLIS (S.F.), HAMERS (F.P.), DE GROOT (J.C.), SMOORENBURG (G.F.) - Perilymphatic application of alphamelanocyte stimulating hormone ameliorates hearing loss caused by systemic administration of cisplatin. Hear Res, 2004, 189: 31-40. STRAIN (G.M.) - Aetiology, prevalence and diagnosis of deafness in dogs and cats. Br Vet J, 1996, 152: 17-36. STRAIN (G.M.) - Deafness prevalence and pigmentation and gender associations in dog breeds at risk. Vet J, 2004, 167: 23-32. SAJJADI (H.), PAPARELLA (M.M.) and CANALIS (R.F.) - Presbycusis. In: Canalis RF and Lambert PR, eds., The Ear: Comprehensive Otology. Philadelphia; Lippincott Williams and Wilkins; 2000. TAYLOR (S.M.) - Head Tilt. In: Nelson RW and Couto CG, eds.; Small Animal Internal Medicine, 3rd ed. St. Louis: Mosby; 2002. LECOUTEUR (R.A.) - Feline vestibular diseases – new developments. J Feline Med Surg, 2003, 5: 101-8.

How to contact the FECAVA Office and Secretary Our Secretary is Dr. Laureline Ziwny You can contact Laureline: By phone : +32 (0)2 533 70 26 By e-mail : [email protected] The times which you can speak to Laureline direct are: Mondays to Thursdays from 9.30 am to 3.30 pm The office is open from 8.30 am to 4.30 pm Monday to Friday but outside Laureline’s hours you may get a member of the FVE Secretariat

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ENDOCRINOLOGY COMMISSIONED PAPER

Rehabilitation Therapies for musculoskeletal and spinal disease in Small Animal Practice M. R Owen(1) INTRODUCTION Increasingly, companion animal veterinary health professionals are seeking rehabilitation therapies for animals under their care suffering from or recovering from musculoskeletal and or spinal injury/disease. In man, rehabilitation therapy has the potential to assist, accelerate or enhance clinical outcomes following orthopaedic or neurological compromise and this, amongst others, is the reason that rehabilitation features in human patient care. The same ideals apply in veterinary care and under optimal conditions, rehabilitation forms part of ‘best clinical practice’ and attention to rehabilitation should not be reserved for attempted rescue of poor clinical outcomes. The increasing intimacy of the professional relationship between physiotherapists (who have trained and who are registered for treating animals) and veterinary surgeons has fostered the opportunity to provide rehabilitation therapies to companion animals. Rehabilitation therapies and strategies are as yet still novel in veterinary care and there is still much to learn regarding the application of and the indications for rehabilitation activities and therapies towards the spectrum of orthopaedic and spinal disease encountered in small animal practice. Veterinary clinical research is providing evidence of efficacy of designated rehabilitation programmes and practices for specific musculoskeletal problems. However, for the most part, we are currently applying rehabilitation therapies to our veterinary patients considering the principles of basic science of tissue healing, by extrapolating from human clinical practice and by reference to veterinary anecdote and small case studies. Only further prospective controlled clinical studies will enable us to identify and evaluate the treatment efficacy of specific rehabilitation practices and therapeutic modalities used in each of the clinical conditions we treat. This article aims to provide the reader with a brief introduction to some of the therapeutic interventions and exercises that are used in rehabilitation. recovery period, when patients are not capable of unassisted voluntary function, therapeutic exercise activities are an invaluable way of promoting musculoskeletal metabolic and physiological function. In the author’s opinion, whenever possible, therapeutic exercises in which the patient actively engages and uses musculoskeletal function are preferable to passive movements performed by the operator, since the latter do not necessarily promote return of voluntary function.

This paper was commissioned by FECAVA for publication in EJCAP

Therapeutic exercise on land Early return to function generally provides the best opportunity for the fullest recovery following orthopaedic or spinal injury/ disease. This is because restoration of activity assists return of normal tissue physiology and biological function. During the

In a rehabilitation programme, specific therapeutic exercises are selected and performed in accordance with the needs of

It is beyond the scope of this article to provide a comprehensive review of the subject and the interested reader is recommended to refer to the texts in the Further Reading list. (1) Dr Martin R Owen BVSc BSc PhD DSAS (Orth) MRCVS RCVS Specialist in Small Animal Surgery (Orthopaedics) Senior Lecturer in Small Animal Surgery (Orthopaedics), Companion Animal Studies, Department of Veterinary Clinical Science, University of Bristol, Langford House, Langford, Bristo l, GB- BS40 5DU. E-Mail: [email protected]

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injury/surgery. Animals that cannot support their own weight can be assisted to stand so that muscular function is promoted. Patients unable or unwilling to support their own weight can be further assisted to perform these activities by supporting their weight, either using a harness or slings [Figure 1] or exercise balls or rolls [Figure 2]. Many patients appear more willing to attempt to use their limbs when supported over a ball or roll than when they are suspended in a harness hence use of the former is generably foreferable. In patients with neurological compromise, assisted standing exercise encourages neuromuscular function, ‘re-educates’ and enhances stamina of muscles and may assist ‘proprioceptive learning’. ‘Sit to stand’ exercises are the author’s preferred rehabilitation activity for dogs recovering from spinal injury/disease since physiological movements of the limbs can be simulated (even in animals with no voluntary movement in the pelvic limbs) and positioning patients as if standing appears to promote muscular contractions, rather than the muscular relaxation observed when passive ranges of motion (ROM’s) are performed on recumbent patients. When dogs have the ability to perform ‘sit to stand’ transitions without assistance, voluntary repetitions can be encouraged using treats and praise. Figure 1 Paraplegic dog assisted to stand using harness

Use in orthopaedic patients In orthopaedic patients, assisted postural activities encourage patients to use their limb through a controlled range of motion that is not achieved when the patient avoids using its limb, instead maintaining a non-weight bearing lameness. Furthermore, joints are encouraged to flex and extend and muscles are actively flexed and passively stretched through greater ranges than occur during ambulation. Excursions of limb segments and the amount or duration of weight-bearing can be manipulated using exercise rolls or balls to provide additional challenges for the patient e.g. encouraging placement of the fore paws on the roll. [Figure 3]. During therapeutic exercises patients should be given rest periods so that fatigue does not limit their value. Initially, 10-15 repetitions may be performed 3-5 times per day , with intensity of exercise increasing and the assistance provided by the clinician decreasing during patient recovery.

the patient and the goals of the rehabilitation programme. During recovery, as tissues heal and neuromuscular and/or musculoskeletal function improves, therapeutic exercises are accordingly modified or increased in intensity to maximise their therapeutic benefit. Examples of therapeutic land exercises include postural exercises (‘sit to stand’), controlled leash activities, negotiating stairs and obstacles, dry treadmill locomotion, ‘dancing’ and ‘wheel barrowing’, controlled playing with obstacles, reaching for toys/food etc. Postural exercises (‘sit to stand,’ ‘lie to stand’ transitions, ‘assisted standing,’ resisted joint flexions ) These activities are useful for patients with severe musculoskeletal or neuromuscular injury/disease which are unable to support their own weight and also for patients recovering from orthopaedic Figure 2 Tetraparetic dog supported on a ‘Physio Roll®’ facilitating postural exercises and ‘proprioceptive training’ exercises

®

Figure 3 Encouraging placement of the fore paws on the roll.

Lowri Davies, Smart Clinic, Swansea

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Figure 4 Walking on a treadmill can encourage limb use when a dog is reluctant to use the limb on land. Treadmill activity can promote normal gait patterns.

Figure 5 Limb use can also be encouraged by ‘wheel barrowing.’

experience can be lessened if a handler walks alongside the patient, or encourages the patient, at the front of the treadmill. A harness is helpful to prevent the patient from migrating off the side of the treadmill and raising the treadmill into an uphill slope appears to assist accommodation to the experience in naive patients. The challenge of the moving belt encourages use of limbs that are not used during over-ground ambulation and the ability to control patient velocity enables challenge to co-ordination, balance and proprioception. The moving belt provides passive extension of the limbs during stance and this may facilitate extension of joints (hence ROM) that does not occur during voluntary overground locomotion.

Modified locomotion activities Perhaps unlike many human patients, once they are able to walk, or use an injured limb, most of our companion animal patients appear to attempt to return to levels of voluntary activity and function achieved before injury/disease with minimal encouragement. Consequently, for veterinary patients, as soon as voluntary ambulation is possible and safe, these patients can be challenged with modified locomotion exercise activities designed to increase their strength, endurance, ROM and/or proprioceptive function. Encouraging patients to actively move their limbs through exaggerated ranges of motion (compared to those achieved during normal gait) is generally better tolerated than trying to achieve enhanced ROMs by passive movements.

Limb use can also be encouraged by ‘dancing’ and ‘wheel barrowing.’ [Figure 5] These activities result in increased extension of the shoulders/hips and increased weight is carried by the two limbs on the ground. Where it is safe, patients can be encouraged to ‘jump up’ into the dancing position to further encourage limb strength. Patients are rapidly fatigued by wheel barrowing and dancing and some may not take to these activities readily initially, hence for some patients, for reasons of operator safety, a muzzle should be used at least initially.

In the early recovery period, normal limb use is generally promoted best by restricting patient velocity, since at speed, holding the limb off the ground is encouraged. Sometimes it is necessary to enforce excruciatingly slow leash walks in order to persuade patients to use their limb but speed can be increased once the patient relearns a normal pattern of gait in which the limb is used. In order to transfer increased weight on to the limbs, patients can be made to negotiate slopes and steps/stairs. Stair climbing should be performed in a slow controlled manner to ensure that reciprocal limb use occurs, rather than hopping or jumping. Compared to over-ground walking, stair climbing results in greater excursions of the limb segments and the challenge that stair climbing poses to patients can encourage limb use where there is reluctance. Encouragement to negotiate obstacles on the ground such as rocks, boxes, a ladder placed on the ground or Cavaletti rails are all effective ways to promote use of a limb in orthopaedic patients. The modified gait required to negotiate the obstacles requires balance, it results in recruitment of different muscle contraction activities compared to simple flat ground walking and these activities provide proprioceptive challenges for animals recovering from neurological dysfunction.

Once healing/recovery is sufficient and simple ambulatory function is restored, increased intensity activities can be introduced in order to promote a return to pre-injury levels of function. When return to a previous level of significantly athletic function is the goal of rehabilitation therapy, activities including ball chasing, running around obstacle courses, controlled jumping etc can be introduced. These will expose tissues to stresses and movements early in the healing period, to facilitate tissue remodelling during healing. Extreme care should be taken to avoid applying excessive stresses to healing tissues which may impair outcomes. At this stage of recovery, most athletically inclined pets will take care of their own rehabilitation programmes and will regain acceptable levels of pet function. Some dog and cats will pursue the dot produced from a laser pointer and this can be an effective way of promoting physical activity indoors. Less athletically-minded pets can be motivated to exercise or perform activities with judicious temptation with treats, or using toys.

Ambulatory function can be promoted by treadmill walking [Figure 4]. Dogs generally adapt rapidly to treadmill locomotion within a few minutes of exposure and resistance to the unfamiliar

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Figure 6. Weight shifting exercise. The patient’s hind limbs are placed onto a balance cushion and the hindquarters are displaced, altering the body’s centre of gravity. This activity is intended to assist ‘proprioceptive learning’

Figure 7. A horizontally placed elevated ladder provides a simple alternative to Caveletti poles. Walking through the ladder provides a challenging environment to the patient and this encourages neuromuscular control and exaggerates normal musculoskeletal function.

Proprioceptive Training All voluntary musculoskeletal movements are controlled by proprioception and therefore all patient motivated activity and all the therapeutic exercises described may be considered to contribute to proprioceptive training. Some addition to these specific activities which require patients to perform or to resist deliberate movements may assist or accelerate the return of proprioceptive functions impaired by neurological injury/disease. These include weight-shifting exercises, in which the patient stands and its balance is challenged with a laterally applied push, encouraging a sway. Patients that are unable to stand can be assisted to stand (e.g. on an exercise roll) and the patient’s balance can be challenged by displacing either the patient or the exercise roll, both craniocaudally and from side to side. Maintenance of balance requires controlled muscular contraction that resists the swaying. The patient’s centre of gravity can also be redistributed by lifting single limbs off the ground, one at a time. To maintain balance, different muscle groups must be contracted according to proprioceptive input. Balance boards, platforms, cushions and trampolines can also be used to challenge the patients ability to remain balanced whilst equilibrium disturbing displacements are applied either to the patient or the surface on which the limbs are placed. [Figure 6]. Ambulatory patients can be encouraged to negotiate challenging surfaces such as partially inflated air beds, Cavalettis (or a ladder placed horizontally), deep grass, or rocky ground that require deliberate limb movements which differ from locomotion on flat ground. [Figure 7] The value of these activities in accelerating or improving proprioceptive function beyond that which occurs with controlled normal activity in companion animals remains to be quantified.

this species is limited. The therapeutic value of aquatic exercise is due to the physical properties of water and the opportunities for performing activities in the aquatic environment that differ from those performed on dry land. Physical properties of water and physiological effects of the aquatic environment Between the temperatures of 0 and 100oC, at atmospheric pressure, water is a liquid and its density is markedly greater than that of air. The specific gravity (a measure of relative density) of pure water is 1.0. The specific gravities of body tissues range from 0.8 (fat), through 1.0 (lean muscle) to 2.0 (bone). When immersed in water, objects are apparently less heavy than they are on land due to the effect of buoyancy. Buoyancy occurs due to the displacement of water which occurs on immersion. The buoyancy of an animal in water, specifically whether or not a patient can float, is a function of its overall body density: animals with a specific gravity of less than 1.0 will float in water, whilst those with a specific gravity of greater than 1.0 will sink. If the depth of water is sufficient, buoyancy, or relative weightlessness, facilitates total non-weight bearing exercise (swimming) and at shallower depths enables reduced weight-bearing ambulatory locomotion (wading). The effect of depth of water on buoyancy in the dog has been studied [1] and water depths to the level of the hock result in 91% weight borne in water, whilst only 38% of weight is borne in water depth that reaches the greater trochanter of the femur. [Figure 8 ]. Immersed body parts and tissues are subject to hydrostatic pressure that is a function of the depth of immersion. This raised pressure exerted on immersed tissues can assist extracellular fluid return to the circulation and this environment may be beneficial for swollen joint or oedematous tissues. [2]. The viscosity of water is substantially greater than that of air. Consequently, movement in water encounters marked resistance, requiring greater levels of exertion than comparable movements on land, hence aquatic exercise promotes muscular strength and cardiovascular fitness. The density and viscosity of water also provides a dynamically

Aquatic therapy (swimming and walking in water) Aquatic exercise (known to some as ‘hydrotherapy’) has become a popular activity used in assisting the recovery from musculoskeletal and spinal disease in dogs. Immersion in water is not generally accepted by cats and hence its application in

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38%

85%

91%

Figure 8 The effect of water depth on effective body weight. When immersed to the depth of the hock, effective body weight is 91%. In water to the depth of the stifle, effective weight reduces to 85% and water to the level of the greater trochanter reduces effective weight to 38%.

Figure 9 Swimming against jets to increase exertion (Photo courtesy of Westcoast Ltd)

stabilising environment since all body movements tend to be retarded. Consequently, it is easier to maintain balance in water than on land. The viscosity and relative density properties of water can be exploited to modify exertion levels during aquatic exercise. Judicious application of currents (or ‘jets’) of water can increase the perceived resistance to movement [Figure 9] Increased resistance to movement can also be achieved by increasing the surface area of a body part moving in the water by applying fins.

recommended to gain maximal positive effects of water warmth, without risking heat related complications. Swimming In comparison to walking, swimming is an activity characterised by greater excursions of the limb segment joints. In healthy dogs, swimming results in increased hip joint flexion compared to overground walking and following surgery for cranial cruciate ligament surgery, there is increased flexion of the stifle and of the hock joint during swimming compared to overground walking. [8]. The increased joint excursions achieved during swimming and during ‘water walking’ may be helpful in reducing musculoskeletal stiffness and loss of ROM that is characteristic of orthopaedic disease and surgery. For patient safety, clinical cases should be fitted with a floatation device during swimming, at least until the patient’s ability to swim competently is established. [Figure 10 ]. Non-athletically minded dogs can be encouraged to swim using toys, or if essential, temptation with food treats. [Figure 11].

What are the potential therapeutic effects of aquatic environment exercise? Evidence from studies in man show that exercise in water can improve strength, cardiovascular and musculoskeletal fitness, ranges of motion (ROM) and there can be some beneficial analgesic effects [3.4]. Furthermore, aquatic exercise is more energy demanding than similar exercise on land [5] and consequently, modest velocities of movement in water can promote levels of fitness that would require greater velocities on land. The combination of reduced velocity of exercise with buoyancy results in ‘low impact’ activity in comparison to overground activity in which the potentially deleterious deforming forces to which limb segments are subjected during exercise are reduced. Consequently, higher levels and intensities of exercise can be performed in an aquatic environment than on land with less risk of damage to injured and/or healing tissues. An additional clinically relevant benefit of exercise in water is the associated improved comfort of exercise because movement is damped by the viscous environment in the water, the modification of painful, undamped overground movement to slower controlled movements may be the means by which aquatic exercise can result in increased joint range of motion and in reduced pain. In man, some closed-chain exercises (under water cycling) appear to assist reduction in joint pain and to reduce joint effusion following anterior cruciate ligament surgery [6]. Water temperature must be controlled when aquatic exercise is used as an intended therapeutic intervention and for dogs. Temperatures in the range 26oC and 28oC are generally

For dogs recovering from surgery for cranial cruciate ligament disease, the benefits of high intensity, high frequency post operative swimming had been demonstrated. In a controlled study, a group of home exercise dogs were compared to a group of dogs that were hospitalised for intensive rehabilitation on three alternate weeks during their early recovery period. These dogs swam twice daily for between 10 and 20 minutes, five days a week on these three weeks. Using force plate analysis, six months following surgery, the swimmers were less lame on their operated limb than restricted exercised dogs and in swimming dogs, there was no difference in limb function between their operated and their normal limbs. In the exercise restricted dogs, six months following surgery, limb function was still significantly less in the surgical limbs compared to their normal limbs [7]. Though differences were measurable between these groups six months after surgery by force plate analysis, visual assessment of lameness in dogs recovering from cranial cruciate ligament surgery suggests a greater difference between swimmers and non-swimmers in

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Figure 10 During aquatic exercise for safety patients should be fitted with a flotation device.

Figure 11 Encouraged to swim using toys. (Photo courtesy of Westcoast Ltd).

the early post operative period than is evident six months after surgery. In order to investigate the efficacy of a less intensive post operative swimming regimen that does not require hospitalisation, but to maximise the acceleration in function obtained through post operative swimming, we have proposed a twice weekly post operative swimming protocol for fit and healthy dogs recovering from surgery for cranial cruciate ligament disease.

Aquatic exercise is a popular recommendation by veterinary clinicians for dogs with a wide spectrum of musculoskeletal disorders including developmental, acquired, traumatic degenerative conditions and even diseases for which a diagnosis remains a mystery. Interestingly, meta-analysis of clinical studies of aquatic exercise by the Cochrane Collaboration (www.cochrane.org) for the management of pain control in musculoskeletal disorders including osteoarthritis in man has not shown superiority of aquatic exercise compared to over ground exercise. In dogs, with the exception of the post surgical treatment of cranial cruciate ligament disease, the therapeutic value of aquatic exercise in the management of musculoskeletal disease remains to be quantified through a published controlled prospective clinical study.

Swim protocol for eight week post operative recovery period following cranial cruciate ligament surgery [9] Swim 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

Time (minutes) 5 5 7 10 6 8 10 6 8 10 6 8 10 8 10 10

Pool Jet Power 0 0 0 0 10% 10% 10% 25% 25% 25% 50% 50% 50% 75% 75% 100%

Swimming for dogs with neurological disease Immersion in water can provide a stimulus for voluntary limb movement in dogs with neurological or neuromuscular disease. Dogs that have insufficient function to display voluntary limb movement on land can demonstrate limb movement when encouraged to swim. This may due to the stimulus of the immersion in water and perhaps the different neuromuscular recruitment that occurs during swimming compared to overground locomotion. Alternatively, movement may occur because there is sufficient strength to move the limbs when the body is buoyant in water but insufficient strength to support body weight on land. Regular swimming sessions can be a useful stimulus to encourage return of voluntary movement in plegic dogs and when swimming, greater joint excursions are achieved compared to impaired overground ambulation. Swimming also enables muscular strength and fitness training without injury through abrasion or falling on the ground. Swimming has been suggested to be as an important aid in recovery following spinal dysfunction presumed secondary to fibrocartilagenous embolic disease [10]. The beneficial effects of swimming for veterinary neurological patients have not been quantified in comparison to non-swimming matched controls in published clinical studies.

When jets are used, swimming starts and also ends with an additional period of 1 minute swim without jets. For jet swims, for the first half of the swim the dog swims into the jet stream, subsequently, the dog swims with the jet stream.

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Figure 12 Using a ‘Physio Roll®’ as a safe ‘back stop’ to encourage walking on the belt during UWTM (Photo courtesy of Lowri Davies)

Figure 13 Buoyancy aid applied to the distal limb to modify limb segment excursions in the UWTM. (Photo courtesy of Lowri Davies)

Walking in water and under water treadmill (UWTM) activity In water, the nature of movement of the joints and limb segments differs to compared to overground locomotion. For dogs walking on water treadmills this effect is influenced by the depth of water used. Typically, carpal and tarsal flexion increases as water level increases from ground level up to the level of the carpus. Additional increase in water level towards level of the elbow/stifle joint appears to result in increased elbow/stifle flexion. Water depth seems to have less influence on flexion of the hip/shoulder. The modified gait exhibited by dogs walking in water is also seen in dogs with mild neurological deficits and it appears that when walking in water, the tendency for these dogs to walk with their paws ‘knuckled over’ is lessened. In such cases, correct placement of the paws may be assisted by the water’s resistance to movement, that results in splaying of the toes, the webbing between the toes acting as a ‘fin.’ As the splayed toes are pushed against the water, the feet tend to land properly. Correct placement of the paws may assist ‘proprioceptive training’ though clinical studies are required to ascertain and quantify the therapeutic benefit of this phenomenon in dogs. In deep water, in addition to the paw positioning effect, there is an effect of enhanced dynamic stability due to the combined effects of buoyancy, viscosity and relative density of water. Consequently a deep water environment can assist locomotory function and musculoskeletal activity for dogs with weakness, severe marked neuromuscular dysfunction or lameness. For dogs showing progressive clinical improvement, the depth of water used in the UWTM can be progressively reduced in accordance with the improvement in locomotor function, working towards return to unassisted locomotor function. The duration of each period of activity in the UWTM should be short enough so that fatigue does not limit function. Hence multiple repeats of short periods of activity are recommended, allowing recovery between active periods. The duration and intensity of exercise can be increased (by increasing velocity of movement or depth of water) in accordance with increase in function during clinical recovery.

UWTM for orthopaedic disease Characteristically, following orthopaedic injury of surgery, painful joints are held in a degree of flexion in order to protect the limb from potentially injurious forces and the potentially painful stimulus of load-bearing. For dogs recovering from musculoskeletal injury and disease, the beneficial effects of buoyancy created by deep water can be exploited to encourage ambulatory limb function in diseased/operated limbs. Using an UWTM, water depth can be adjusted (increased as necessary) to ensure that the diseased limb is voluntarily extended and that functional steps are made using the limb. The moving belt of the treadmill is an unfamiliar experience for most patients and reluctant walkers can be effectively assisted to walk on the belt by an assistant restraining and encouraging the patient. Placing a large soft object (e.g a gym roll or ball) into the water behind the dog, at the back of the treadmill provides a soft effective back of the treadmill, which encourages dogs to move forward onto the advancing treadmill belt. [Figure 12] In deep water, buoyancy can also be used to assist joint excursion by application of a floatation device to the distal limb segment (e.g to the carpus/tarsus). Such application increases passive elbow/ stifle joint flexion in deep water. In contrast, assisted extension of an injured limb can be encouraged by applying a buoyancy aid to the contralateral (normal) distal limb. [Figure 13] The resultant increased swing phase on the normal limb encourages extension and stance on the injured limb. Hence the aquatic environment can be used to facilitate soft tissue stretching and when limb use improves, this form of exercise can be employed to improve muscular strength and to promote use of the limb during overground ambulation. [11] have described the use of under water treadmill exercise alongside postoperative physiotherapy for a small group dogs recovering from surgery for cranial cruciate ligament disease. Following suture removal 10 days after surgery, water treadmilled dogs were exercised three times per week in the treadmill. Six weeks following surgery, thigh muscle mass of the surgical limbs (measured as thigh girth) was greater in UWTM dogs compared to homeexercised dogs.

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Figure 14 Application of cold therapy to the stifle joint following recent surgery. Cold packs should not be applied directly to the skin. To avoid cold burns, a moistened towel can be used as an insulating layer which facilitates transfer of heat energy. Despite the popularity of the recommendation UWTM aquatic exercise by veterinary clinicians for dogs with musculoskeletal injury/disease, to date, the author is not aware of evidence of efficacy of this exercise modality compared to over-ground exercise from clinical studies of large numbers of dogs. Figure 15 Using a hair dryer to warm tissues

Physical Agents Heat, cold, low frequency ultrasound, electrical stimulation, laser and extra-corporal shock waves are some of the physical agents used in rehabilitation programmes for musculoskeletal and neurological injury and disease.

using the following guidelines: 1. Use cold therapy within the first 24-72 hours of acute injury 2. Use ice packs or commercial cold packs chilled to temperatures not lower than -20oC 3. Do not apply ice or gel pack directly to the skin. Ensure that a thermal insulating layer is used against the skin. This is especially important when the animal’s hairy coat has been clipped. A moist cloth provides some insulation whilst facilitating transfer of some heat energy [Figure 14] 4. Apply cold source for up to 20 minutes at a time. (Often, “15 minutes on, 15 minutes off” is recommended). 5. Ensure that tissues are given the opportunity to return to their preferred physiological temperature at the end of the treatment period. (Total treatment periods are generally governed by practical constraints but are not normally continued for more than one hour).

Cold (cryotherapy) The application of cold is referred to as cryotherapy. The intention of application of cold is to draw heat energy from body tissues, resulting in a reduction in tissue temperature. Some of the physiological effects of tissue cooling include (but are not limited to) reductions in the following: 1. blood flow 2. inflammation 3. oedema 4. local tissue metabolism 5. pain sensation 6. spasticity

The relative analgesic efficacy afforded by cold therapy compared to postoperative bandaging has not been investigated in companion animals and in general, it is the author’s preference to apply dressings in the immediate postoperative period to control swelling and to protect limbs from painful jarring movements. Cold therapy can be applied through light postoperative dressings since light bandages are not total insulators of heat/cold.

and an increase in the factors below: 1. tissue stiffness 2. muscle viscosity (resulting in reduced ability to contract/extend rapidly) Application of cold is indicated to assist the management of the following conditions 1. acute injury 2. acute inflammation, swelling or oedema 3. to increase range of motion (ROM) when it is limited by pain

Heat Superficial heat therapy The intention of heat therapy is to increase the temperature of the treated tissues. This can be achieved superficially (up to 2cm depth) using conduction, radiation and convection from

Care should be used during the application of cold to avoid thermal injury to the tissues (frostbite). Injury should be prevented

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external heat sources. Examples of heat sources for superficial warming include warm packs, spas and whirlpools, infra red lamps and warm air heaters/hair dryers [Figure 15]. Warming of deep tissues requires transfer of energy to deep tissue that is absorbed and converted to heat energy. Heating of deep tissues is achieved using ultrasound (US) and electricity (short wave diathermy).

although enhanced fracture healing has not been demonstrated in controlled conditions in dogs. Treatment guidelines include: 1. use a water-soluble gel as a coupling agent to the skin to facilitate US transmission. 2. use a coupling cushion if the US head does not conform to the surface of the tissues treated. 3. follow the application guidelines applicable to the power rating and the frequency delivered by the US unit used to ensure tissue heating and to avoid thermal injury. 4. consider any vocalising or avoidance behaviour to be attributable to discomfort and stop treatment. Use lower intensity or duration of treatment next time. 5. treat for approximately 4 minutes for each position of the sound head and for a maximum of four adjacent positions of the sound head per session. 6. keep transducer moving at approximately 4cm per second to avoid localised overheating of tissues.

Some of the physical effects of heating tissues include (but are not limited to): 1. relief of pain and spasm 2. increased tissue compliance 3. increased blood flow 4. increased tissue metabolism 5. increased muscle relaxation 6. increased capillary permeability (which can promote oedema) Application of heat is indicated in the following conditions: 1. chronic musculoskeletal discomfort 2. decreased ROM due to stiffness

Electrical stimulation Electrical stimulation of tissues is primarily used in veterinary care to assist pain control and to increase muscle strength. Amelioration of pain is achieved by the depolarisation of sensory nerve fibres whilst electrically induced muscle contraction is achieved by motor nerve depolarisation.

Heat should be applied according to the following conditions: 1. Apply hot packs (generally not hotter than 75oC) using thermal insulation padding. 2. Heat pack Temperature should be tested against the operator’s skin if there is any uncertainty regarding the risk of causing a burn to the patient. 3. Apply heat packs for 15 to 30 minutes. 4. Thermal baths and whirlpools should be used at temperatures not exceeding 35oC. Locally applied warm water can generally be used safely at higher temperatures (up to 40oC).

Variables in electrical stimulation A wide variety of electrical stimulators is commercially available, many of which produce unique combinations and ranges of electrical outputs. The variability of the output includes – frequency. – amplitude (the maximum electrical current delivered). – waveform (symmetric, asymmetric, balanced, unbalanced, bi/mon/polyphasic etc). – polarity. – pulse rate. – ramp (rate of acceleration of amplitude from start of pulse to peak amplitude).

Heating of deep tissues In small animals, even deep tissues may be heated using superficial heat therapy. For example, the joints of small animals will be warmed when heat packs are applied because the depth of the tissue will not exceed 2 cm from the skin surface in many patients. Heating of deeper tissues by an energy source requires transmission of energy and conversion to heat energy because sufficient transfer of heat from superficial application cannot occur without burning. This can be achieved using relatively low frequency (approximately 20 kHz to 3MHz) ultrasound (US). Tissue heating so created tends to be of short duration following treatment and treatment periods are generally in the region of 10 minutes. A hairy coat absorbs US and results in poor transmission of energy and consequently, skin must be clipped to enhance energy transmission to the tissues. Debate continues regarding the therapeutic efficacy of deep tissue heating in human medicine [12] and its efficacy in companion animals is also undetermined. However, commercial recommendations suggest that emission intensity of 1.0W cm2 and higher for 10 minutes heats tissues. In order to achieve thermal effects an elevation of tissue temperature of 1oC to 4oC is recommended.

Different models of stimulator claim to be more appropriate for specific applications e.g. pain control. Electrical energy is delivered to tissues using surface electrodes. Ideally these are flexible so as to conform to the tissue to which they are applied. Some (single use) electrodes can be trimmed to size so that they fit well and so that they only stimulate the tissues of interest. (If electrodes are too large, they will stimulate unwanted muscle groups to contract). Electrodes should have a low resistance and conduction to the skin can be increased using appropriate gel. Electrical stimulation for pain control Guidelines for electrical stimulation for pain control in animals are limited and are based extrapolation from use in man and on small studies performed in dogs. One study showed significant improvement in limb function in dogs with chronic stifle osteoarthritis for up to 180 minutes following electrical

Suggested clinical indications for tissue heating by US include tendonitis and bursitis and joint contracture secondary to chronic inflammation or immobilisation. Studies in man suggest that US can accelerate soft tissue healing and fracture healing,

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stimulation [13] .Daily treatments are recommended although the duration of analgesia provide by stimulation is poorly quantified. Treatment periods of 20-30 minutes are recommended using 50150 Hz with pulse duration of 2-50 microseconds for acute pain and 100-400 microseconds for chronic pain. The relative value of interferential, premodulated interferential or pulsed current (AC or DC) waveforms is, as yet, unquantified in companion animals. Electrically induced muscle contraction When a patient is not or cannot voluntarily use its limb, electrical muscle stimulation can help reduce loss of muscle strength. The ideal delivery of electrical stimulation is unknown but small clinical studies suggest that stimulation frequencies between 25 and 50 Hz produce strong titanic contraction whilst minimising fatigue. A symmetrical biphasic pulse is preferred and is allegedly the most comfortable waveform according to some reports in man. Pulse durations of 100 to 400 microseconds with ramp durations of 2-4 seconds should also maximise comfort in dogs. [14]. Treatment frequencies of five times per week have been used, though daily treatment may seem equally sensible.

What is ESWT? Shock waves are high energy, high amplitude acoustic pressure waves generally in the range of 20-100 megapascals (MPa). Shock waves are generated in a liquid medium by the conversion of electrical activity to mechanical energy by electrohydraulic, electromagnetic or piezoelectric transducers. The waves are characterised by a massive rapid rise in energy and a subsequent exponential decay, all of which takes place in approximately 300 nanoseconds. [Figure 16]. Shock waves travel through tissues and energy is released at boundaries between different tissue densities, at bone-tendon interfaces, for example, generating heat. Shock waves have direct effects (compression and tension) and indirect effects (cavitation, tension and shear) on tissues. The microscopic disruption to tissue may be the mechanism by which ESWT modifies tissue physiology. ESW treatment results in induction of cytokines and growth factors including transforming growth factor 1, substance P, osteocalcin and vascular endothelial growth factor [18]. Nitric oxide synthase induction is also stimulated, and this may an important part of the mechanism by which ESWT influences bone healing. Inhibition of afferent pain signals may occur secondary to stimulation of nociceptors.

Patient safety: Operators must receive appropriate training before using electrically operated energy transmitting devices in rehabilitation programmes

Figure 16 Profile of an extracorporeal shock wave showing the rapid rise in energy and short duration of the acoustic wave. As the energy is released in the tissues, there is negative pressure.

Laser treatment The type of laser used in injury and disease is the low-level laser, which typically produces an output of between 1 and 5 mW. There are several types of emitters, but Helium-Neon (HeNe) is one of the most popular laser used in human and in veterinary work, emitting visible red light with a wavelength of 633nm. The therapeutic application of lasers has been investigated since the 1970s and putative therapeutic indications include soft tissue wound healing, osteochondral wound healing, management of osteoarthritis, pain control and regeneration of spinal cord following injury. The under pinning mechanistic theory of laserinduced tissue response is that photons are delivered to tissues, absorbed by chromophores and cytochromes resulting in oxygen production, stimulating the formation of proton gradients across cell membranes. These changes result in ATP production and cellular metabolism and growth are up regulated. Unfortunately the results of laboratory studies that document enhanced soft tissue and osteochondral healing have not been reproduced in published clinical studies in man or companion animals and hard evidence to support laser therapy for enhanced tissue healing in wounds in healthy animals is not currently available. In man, the value of laser therapy has been investigated for the management of knee pain due to osteoarthritis [15,16,17]. Interestingly, positive results appear more likely when the study is published in a journal containing ‘laser’ in its title.

Shock waves can be delivered to tissues in a focussed manner to a small area of tissue, in which depth of penetration can reach 11cm. Radial application delivers to the surface of the body resulting in dispersion of energy over a wide and predominantly superficial area. [Figure 16] Application of ESWT in veterinary medicine is established in equine work for the treatment of a spectrum of musculo-skeletal disorders including suspensory ligament desmitis, tendinopathies, back pain, navicular disease, osteoarthritis and stress fractures. [19,20]. There are reports of small numbers of dogs with musculoskeletal disorders (including tendinopathy, tendonitis and osteoarthritis) treated with ESWT [21,22,23]. One of these reports [23] was a controlled study that investigated the efficacy of ESWT in controlling pain in hip and elbow osteoarthritis in dogs.

Extracorporal shock wave therapy (ESWT) In man, some clinical studies have demonstrated therapeutic efficacy of ESWT in the management of delayed and non-union fractures, and pain management of chronic conditions such as lateral elbow pain (‘tennis elbow’), plantar fasciitis, Achilles and patellar tendonitis and osteoarthritis.

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based on manufacturer’s recommendations extrapolated from USWT in man. Recommended treatment protocols for canine musculoskeletal disease are not readily available in the published veterinary literature and controlled studies are needed to fully evaluate and optimise efficacy of treatment.

Conclusions Our knowledge and understanding of the activities, exercises and practices that encompass rehabilitation in veterinary patients is constantly expanding. The expertise in veterinary rehabilitation is largely derived from practices used in human medicine and the veterinary profession has gained much from our developing relationship with our physiotherapy colleagues. Veterinary clinicians should continue to work closely with physiotherapists to ensure that patients under their care engage in appropriate rehabilitation that provide them the best standard of care.

Further reading – Canine Rehabilitation and Physiotherapy. Eds, Darryl L Millis, David Levine and Robert A Taylor, Elsevier Saunders, St Louis, Missouri. (2004) – Rehabilitation and Physical Therapy, Eds David Levine, Darryl L Millis, Denis J Marcellin-Little, Robert Taylor. Veterinary Clinics of North America Small Animal Practice. 35 (2005) – Small Animal Spinal Disorders: Diagnosis and Surgery 2nd Edition Nicholas JH Sharp and Simon J Wheeler. Elsevier Mosby, Edinburgh (2005) Figure 17 Equipment for delivering shockwave therapy (insert of contact endpiece) (Photo courtesy of GHSMedical [Woolf])

References [1] LEVINE (D.), TRAGAUER (V.), MILLIS (D.L.) - Percentage of normal weight bearing during partial immersion at various depths in dogs, In Proceedings of the second International Symposium on Rehabilitation and Physical Therapy in Veterinary Medicine, Knoxville, Tenn, 2002 [2] GEIGLE (P.R.) et al - Aquatic physical therapy for balance: the interaction of somatosensory and hydrodynamic principles. J Aquat Phys Ther, 1997, 5 : 4-10, [3] BRAVO (G.), GAUTHIER (P.), ROY (P.M.), PAYETTE (H.), GAULIN (P.) - A weight-bearing, water-based exercise program for osteopenic women: its impact on bone, functional fitness, and well-being. Arch Phys Med Rehabil. 1997 78 :1375-80. [4] SPEER (K.P.), CAVANAUGH (J.T.), WARREN (R.F.), DAY (L.), WICKIEWICZ (T.L.) - A role for hydrotherapy in shoulder rehabilitation. Am J Sports Med. 1993; 21 850-3. [5] JOHNSON (B.L.), STROMME (S.B.), ADAMCZYK (J.W.), TENNOE (K.O.) - Comparison of oxygen uptake and heart rate during exercises on land and in water. Phys Ther. 1977; 57:273-8 [6] TOVIN (B.J.), WOLF (S.L.), GREENFIELD (B.H.), CROUSE (J.), WOODFIN (B.A.) - Comparison of the effects of exercise in water and on land on the rehabilitation of patients with intra-articular anterior cruciate ligament reconstructions. Phys Ther. 1994 74:710-9. [7] MARSOLAIS (G.S.), DVORAK (G.), CONZEMIUS (M.G.) - Effects of postoperative rehabilitation on limb function after cranial cruciate ligament repair in dogs. J Am Vet Med Assoc. 2002 ; 220:1325-30. [8] MARSOLAIS (G.S.), MCLEAN (S.), DERRICK (T.), CONZEMIUS (M.G) Kinematic analysis of the hind limb during swimming and walking in healthy dogs and dogs with surgically corrected cranial cruciate ligament rupture.J Am Vet Med Assoc. 2003, 222:739-43.

Improvements were documented in limb function (as measured by force plate analysis) and in comfortable range of joint motion following ESWT treatment but not in sham treated controls. ESWT may be a useful adjunct to the management of painful musculoskeletal disease in dogs, particularly if analgesia cannot be safely provided using non-steroidal anti-inflammatory drugs. However, heavy sedation or anaesthesia is required for most forms of ESWT in dogs and this may limit widespread application of the technique. Because ESWT is a local treatment, careful identification of the regional anatomy of the diseased limb is necessary to ensure accurate direction of the shock waves. Treated areas must be clipped to allow transmission of shock waves which is greatly facilitated using ultrasound coupling gel. The potentially injurious effects of cavitation necessitate that EWWT is not applied to the lung field, brain, heart or major blood vessels or nerves Furthermore, care should be taken during treatment because ESWT can produce local tissue damage resulting in bruising, petechiation and haematoma. These effects can be controlled by applying the transducer to soft tissue and not to bony prominences. Excessive treatment can result in thermal tissue damage and following treatment, dogs can be sore for several days, during which analgesia may be required. Claims of the long-term analgesic effect of treatment suggest efficacy for up to 12 months. Currently, treatments are predominantly

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Rehabilitation Therapies for musculoskeletal and spinal disease in Small Animal Practice - M. R Owen [9] OWEN (M.R.) AND HUNT (R.) (2004) Personal communication [10] GANDINI (G.), CIZINAUSKAS (S.), LANG (J.), FATZER (R.), JAGGY (A.) - Fibrocartilaginous embolism in 75 dogs: clinical findings and factors influencing the recovery rate. J Small Anim Pract. 2003, 44:76-80. [11] MONK (M.L.), PRESTON (C.A.), MCGOWAN (C.M.) - Effects of early intensive postoperative physiotherapy on limb function after tibial plateau levelling osteotomy in dogs with deficiency of the cranial cruciate ligament. Am J Vet Res. 2006, 67:529-36. [12] ROBERTSON (V.J.), BAKER (K.G.) - A review of therapeutic ultrasound: effectiveness studies. Phys Ther. 2001, 81:1339-50. [13] LEVINE (D.), JOHNSON (K.D.) - Price MN and others. The effect of TENS on osteoarthritic pain in the stifle of dogs. In Levine D, Millis DL, editors. Proceedings of the Second International Symposium on Rehabilitation and Physical Therapy in Veterinary Medicine. Knoxville (TN): University of Tennessee, University Outreach and Continuing Education 2002, p199. [14] MILLIS (D.L.), LEVINE (D.), WEIGEL (J.P.) - A preliminary study of early physical therapy following surgery for cranial cruciate ligament rupture in dogs [abstract] Vet Surg. 1997, 26:434 [15] DJAVID (G.E.), MORTAZAVI (S.M.J.) - Basirnia A et al. Low level laser therapy in musculoskeletal pain syndromes: pain relief and disability reduction. Lasers Surg Med 2003, 152 (Suppl 15): 43 [16] GUR (A.), COSUT (A.), SARAC (A.J.), CEVIK (R.), NAS (K.), UYAR (A.) - Efficacy of different therapy regimes of low-power laser in painful osteoarthritis of the knee: a double-blind and randomizedcontrolled trial. Lasers Surg Med. 2003, 33:330-8.

[17] ROCHKIN (S.) - The role of laser phototherapy in nerve tissue regeneration and repair: research development with perspective for clnical application. In: Proceedings of the World Association of Laser Therapy, Sao Paulo, Brazil. 2004, P 94-95 [18] WANG (C.J.), WANG (F.S.), YANG (K.D.), WENG (L.H.), HSU (C.C.), HUANG (C.S.), YANG (L.C.) - Shock wave therapy induces neovascularization at the tendon-bone junction. A study in rabbits. J Orthop Res. 2003, 21:984-9. [19] MCCLURE (S.R.), MERRITT (D.K.) - Extracorporeal shockwave therapy for equine musculoskeletal disorders. Compend Contin Educ Pract Vet 2003, 25 :68-75 [20] MCCLURE (S.R.), VAN SICKLE (D.), WHITE (M.R.) - Effects of extracorporeal shock wave therapy on bone. Vet Surg. 2004, 33:40-8 [21] DANOVA (N.A.), MUIR (P.) - Extracorporeal shock wave therapy for supraspinatus calcifying tendinopathy in two dogs. Vet Rec. 2003, 152:208-9 [22] LAVERY (P.H.), MCCLURE (S.R.) - Initial experience with extracorporeal shockwave therapy in six dogs. Part 1. Vet Comp Orthop Traumatol 2002, 15:177-83 [23] FRANCIS (D.A.), MILLIS (D.L.), EVANS (M.) et al. - Clinical evaluation of extracorporeal shockwave therapy for the management of canine osteoarthritis of the elbow and hip joints. In Proceedings of the 31st Veterinary Orthopaedic Society. Okemos (MI): Veterinary Orthopaedic Society; 2004

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ORTHOPAEDICS REPRINT PAPER (A)

Diagnostic and genetic aspects of patellar luxation in small and miniature breed dogs in Austria B. Vidoni(1), I. Sommerfeld-Stur(2), E. Eisenmenger(1) SUMMARY During a period of eight years (1996 – 2004) 432 small and miniature breed dogs were screened for patellar luxation (PL). In order to achieve the diagnostic accuracy required for genetic screening to assist breeding programmes, examinations were based on the concept of a standardized examination protocol for patellar luxtion. Diagnostic criteria assessed by physical examination, inspection and palpation focussed on lameness, evaluation of patellar tracking in the standing and recumbent position, with special focus on patello-femoral instability, as well as on the deviation of the tibial tuberosity and any perceivable crepitation of the stifle joint during manipulation. Evaluation of all findings was made on the basis of PUTNAM´s (1968) classification. Radiographic examinations were not performed. Patellar luxation (unilateral or bilateral, medial and/or lateral) was diagnosed in 61.6 % of the examined dogs, but permanent lameness was only present in 15.5 % (right stifle) and 12.8 % (left stifle), respectively. Intermittent lameness was observed in only 3.5 % (right stifle) and 4.6 % (left stifle), respectively. This means that almost 40 % of all dogs with patellar luxation are asymptomatic and their condition would not have been detected without diagnostic screening. The different diagnostic criteria showed significant correlation between each other and with the final findings. In some parameters like “luxation in standing position“ and “luxation in recumbent position“, the correlation with final findings was particularly high. Thus, the examination protocol used in this study appears to be suitable for PL screenings in dogs. Investigation of the influence of parameters like body weight, age, gender and neutering on the presence of PL showed that, except for gender, all attributes were associated with the occurrence of PL. An increase in body weight of 1 kg decreased the odds of suffering from PL to the 0.8fold (p