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Foot

A Review of Current Treatments for Plantar Fasciitis

Benedict F DiGiovanni, MD1 and Andrew M Moore, MD2 1. Director, Foot and Ankle Fellowship Program, University of Rochester Medical Center Orthopaedics, and Director, Musculoskeletal Curriculum, University of Rochester School of Medicine; 2. Orthopaedic Foot and Ankle Fellow, University of Rochester Medical Center

Abstract Plantar fasciitis is the most common cause of plantar heel pain. Usually, diagnosis can be made entirely based on history and physical examination. For the vast majority of patients, symptom resolution can be expected within 10 months of symptom onset. For some, however, the symptoms can be debilitating and long-lasting. The goals of treatment are to decrease pain, increase function, and shorten the duration of symptoms. Nonoperative treatments include plantar-fascia-specific stretching (PFSS), night splints, orthotics, casting, steroid injections, anti-inflammatory medications, extracorporeal shock-wave therapy, and surgery. This article reviews the available literature—with particular emphasis on levels of evidence—and outlines the authors’ own preferred strategies for managing patients with this condition.

Keywords Plantar fasciitis, heel pain Disclosure: The authors have no conflicts of interest to declare. Received: January 21, 2010 Accepted: February 26, 2010 Citation: US Musculoskeletal Review, 2010;5:70–4 Correspondence: Andrew M Moore, MD, Division of Foot and Ankle Surgery, Department of Orthopaedics, University of Rochester Medical Center, 601 Elmwood Avenue, Box 665, Rochester, NY 14642. E: [email protected]

Plantar fasciitis is the most common cause of plantar heel pain and is responsible for approximately one million office visits each year to primary care physicians and orthopaedic surgeons.1 Usually, diagnosis can be made entirely based on history and physical examination. For the vast majority of patients, symptom resolution can be expected within 10 months of symptom onset. For some, however, the symptoms can be debilitating and long-lasting. Numerous treatment options exist, including stretching, night splints, orthotics, casting, steroid injections, anti-inflammatory medications, extracorporeal shock-wave therapy, and surgery. Historically, few level I or level II evidence studies (see Table 1) have been available to guide treatment, particularly for chronic or recalcitrant cases. This article will provide a review of the subject and outline the available literature and the authors’ own preferred strategies for managing patients with this condition.

Anatomy and Pathophysiology The plantar fascia is comprised of three relatively inelastic bands of fibrous tissue that originate on the anteromedial aspect of the calcaneal tuberosity and insert  at the bases of the proximal phalanges. As this structure courses distally from its origin deep to the plantar fat pad of the heel, it becomes subcutaneous and is easily palpated beneath the longitudinal arch along the plantar aspect of the foot. Tension developed by dorsiflexion of the toes during the stance phase of gait tensions the plantar fascia, which transmits tensile loads to its calcaneal origin. This transmission of tensile loads, which is greatest beneath the first ray,3 elevates the longitudinal arch, which is referred to as the windlass

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mechanism. Repetitive activation of the windlass mechanism, as one might see in runners or in standing workers, may result in mechanical (tensile) overload, microtears, inflammation, and chronic degenerative changes in the plantar fascia origin.4 Plantar calcaneal enthesophytes, or ‘heel spurs,’ commonly involve structures deep to the plantar fascia origin, including the flexor digitorum brevis, the abductor digiti minimi, or the short plantar ligament.5 They are no longer thought to be causative or even strongly associated with clinically symptomatic plantar fasciitis.6

Diagnostic Considerations The diagnosis of plantar fasciitis is made by a patient’s characteristic history of symptoms, and is supported by physical exam findings. Patients typically complain of plantar heel pain that is slowly progressive and is most noticeable with the first step in the morning or after sitting for an extended period of time. Pain is described as sharp or shooting with the first few steps, progressing to a dull ache by the end of the day. It is useful to ask patients to point with one finger to the area of maximal pain, which is usually at the proximal aspect of the medial longitudinal arch at the medial tubercle of the calcaneus on the plantar aspect of the heel. Patients exhibit tenderness here  that is typically worsened by concomitant passive dorsiflexion of the ankle and toes, which tensions the plantar fascia. Palpation should also confirm the presence of a tight fascial band in order to exclude a partial or complete attenuation or rupture of the plantar fascia. In our practice, patients are routinely

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assessed with regard to their standing alignment (including hindfoot alignment and longitudinal arch) and the presence or absence of an Achilles or isolated gastocnemius equinus contracture.

Table 1: Levels of Evidence in Studies Investigating the Results of a Treatment 2 Level of Evidence

Study Characteristics

The differential diagnosis for plantar heel pain includes tarsal tunnel syndrome (TTS), entrapment of the first branch of the lateral plantar nerve (FBLPN, also known as ‘Baxter’s nerve’), radiculopathy, calcaneal stress fracture, and central heel pain syndrome. TTS may be subdivided into proximal and distal TTS: the former refers to compression neuropathy of the tibial nerve beneath the flexor retinaculum due to a variety of causes; the latter refers to compression of one of the terminal branches of the tibial nerve, often by the deep fascia of the abductor hallucis muscle. Patients with proximal or distal TTS may complain of a burning or tingling component to their pain, with symptoms reproduced by percussion over the course of the tibial nerve within the tarsal tunnel. The windlass test for plantar fasciitis and the dorsiflexion– eversion test for TTS both increase tension on the plantar fascia and tibial nerve and its branches, rendering these two tests unreliable for distinguishing these two clinical entities.7

I

High-quality RCT

II

Prospective cohort study, lower-quality RCT

III

Retrospective cohort study

IV

Case series (no control group)

V

Expert opinion

RCT = randomized controlled trial.

Figure 1: Demonstration of the Plantar-fascia-specific Stretching Technique

FBLPN compression or entrapment is thought to be the most common neural cause of heel pain, and produces medial plantar heel pain similar to (and often co-existent with) plantar fasciitis.8 Nerve entrapment usually occurs between the deep fascia of the abductor hallucis and the medial border of the plantar fascia as the nerve course changes from vertical to horizontal as it passes around the plantar–medial border of the calcaneus. Heel pain due to radiculopathy lacks the characteristic start-up pain and discrete tenderness seen with plantar fasciitis. Calcaneal stress fractures can be excluded by the absence of pain reproduced by medial–lateral compression of the calcaneal tuberosity (negative calcaneal squeeze test). Central heel pain syndrome (or calcaneal fat pad atrophy) presents with central plantar heel pain and thinning of the plantar calcaneal fat pad on exam, which is not characteristic for plantar fasciitis. Further diagnostic modalities, including radiographs and nerve conduction studies, may be useful to exclude other diagnoses (such as calcaneal stress fractures or nerve entrapment), although they are not necessary for either the diagnosis or the treatment of plantar fasciitis.9 Likewise, bone scan, ultrasound, and magnetic resonance imaging (MRI) are not usually required to diagnose or treat plantar fasciitis, although the latter two modalities will characteristically demonstrate plantar fascia thickening in patients with plantar fasciitis.10 Occasionally, MRI or ultrasound may be useful to investigate other related diagnostic possibilities, including plantar fascia ruptures, masses, osseous lesions, or heel fat pad abnormalities.11

Non-operative Treatment Stretching The initial treatment of plantar fasciitis is non-operative. The vast majority of patients (90%) respond to non-operative treatment by six to 10 months. For this reason, the American Orthopaedic Foot and Ankle Society (AOFAS) position statement recommends a minimum of six to 12 months of non-operative treatment before surgical intervention is undertaken for this condition.12 The goal of non-operative treatment is to

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reduce pain, improve function, and shorten the duration of symptoms. Although there are numerous options available for the management of plantar fasciitis, there are limited level I and level II evidence studies available to guide non-operative treatment. We will review the available literature and present our preferred methods below. Traditionally, Achilles stretching has been the mainstay of treatment for plantar fasciitis. More recently, plantar-fascia-specific stretching (PFSS), which involves passive ankle and toe dorsiflexion with palpation and massage of the plantar fascia on stretch (see Figure 1), was compared with Achilles stretching in 101 patients with plantar fasciitis of at least 10 months’ duration over an eight-week period. In this prospective, randomized comparison study, both groups were also treated with three weeks of celecoxib and pre-fabricated soft insoles. Eighty-two patients completed the study and, although both groups showed improvement, a statistically significant improvement in pain, activity limitation, and patient satisfaction was found in the PFSS group compared with the Achilles group (level I evidence).13 After eight weeks all patients were converted to the PFSS treatment and, in a two-year follow-up study, data were obtained from 66 patients, of whom 75% had returned to full activity without restrictions. In most cases, patients achieved maximal improvement within six months, with similar improvement in pain between the patients treated initially with PFSS and those who began PFSS after eight weeks (level II evidence).14 These clinical findings are supported by a recent cadaveric biomechanical study that demonstrated combined ankle and toe

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Foot dorsiflexion (similar to that produced by the PFSS technique) resulted in the greatest amount of plantar fascia stretch among 15 different ankle and foot configurations tested.15 Furthermore, a recent finite element analysis of plantar fascia mechanics found that toe dorsiflexion, compared with Achilles tendon force, had a greater impact on plantar fascia strain by approximately a 2:1 ratio.3

employ a short-leg fiber-glass walking cast for approximately  two weeks in patients who have ongoing symptoms despite an appropriate course (generally four to six months) of less restrictive non-operative measures and who are willing to accept the functional limitations and theoretical increased risk of deep  vein thrombosis  (DVT) associated with immobilization.

The use of ankle-dorsiflexion-producing night splints has been studied in a prospective cross-over study of 37 patients with recalcitrant plantar fasciitis. Study participants wore night splints for either the first or the second month and  had no other treatment; at the end of six months, 80% of participants had subjective improvement with statistically significant improvements in AOFAS Ankle Hindfoot Rating System and Mayo Clinical Scoring System scores during the period of splint use (level II evidence).16

Anti-inflammatories

Drawbacks to the use of night splints include poor patient tolerance due to expense, discomfort, and interference with sleeping habits. In a recent randomized controlled trial comparing the use of night splints  with orthotics for the management of plantar fasciitis, inferior results were found among those randomized to using night splints due to poor patient compliance: only one in 28 patients in this group reported they could tolerate the use of a night splint throughout the entire study period of one year.17 In contrast to dorsiflexion night splints, PFSS is associated with higher patient satisfaction, mimics the benefits of night splints (stretching prior to the first step in the morning), and can be performed both night and day, including after periods of inactivity.

Orthotics Orthotic insoles correct mild deformity, support the longitudinal arch, provide cushioning to the foot, and have been widely used in the treatment of plantar fasciitis. In most studies, however, analysis of the efficacy of this treatment modality has been obscured by the use of orthotic insoles only in conjunction with other methods.18 The best available evidence regarding this treatment modality does not support the use of expensive custom orthotics in the management of plantar fasciitis. A prospective, participant-blinded trial with 135 patients randomised to receive either a sham foam insole, a firm prefabricated insole, or a semi-rigid plastic custom insole found a small short-term (three-month) benefit for both pre-fabricated and custom insoles (level I evidence). No long-term (12-month) benefit was found for either a custom or a pre-fabricated insole compared with a sham insole.19 A large multicenter, prospective trial randomized participants with plantar fasciitis into groups that performed stretching alone or in conjunction with either a custom polypropylene insole or one of three different pre-fabricated inserts. After eight weeks of treatment, participants who used a custom insert showed the least improvement, and the authors concluded there was no benefit from the use of a custom insert compared with a pre-fabricated insert for the management of plantar fasciitis (level I evidence).20

Casting To our knowledge, no high-quality studies specifically evaluating the efficacy of cast immobilisation for the treatment of early or recalcitrant plantar fasciitis have been performed. In our practice we occasionally

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Anti-inflammatory modalities are used frequently in the treatment of plantar fasciitis. These include oral medications, local injections, or topical preparations. Based on available level I and level II evidence studies, support for a durable benefit from these treatments is lacking. In a recent randomized controlled trial, 29 patients with plantar fasciitis who were treated with viscoelastic heel cups, night splints, and Achilles stretching were randomized to receive either 200mg daily of celecoxib or placebo for 30 days, in addition to their standard treatment. After one, two, and six months of treatment, the authors were unable to find a statistically significant difference between the groups, although a slight trend in favor of the celecoxib group was found (level II evidence).21 In patients who can tolerate them, we utilize a short-term course of non-steroidal anti-inflammatory medications only as an adjunctive modality for the treatment of plantar fasciitis. Local corticosteroid injection for the treatment of plantar fasciitis was studied in a prospective randomized controlled trial in which 106 patients were randomized into groups receiving a local injection of lidocaine with or without 25mg of prednisolone. Improvement in pain was noted in those participants receiving local injection of prednisolone at one month, but not at three or six months following treatment (level II evidence).22 On the other hand, reported complications of local injection of corticosteroid for plantar fasciitis include plantar fat pad atrophy and plantar fascia rupture; the latter risk may be as high as 10% with steroid injection, with difficult-to-salvage consequences.23,24 Due to the risk of complications and the lack of evidence for long-term benefit, in our practice we do not routinely perform corticosteroid injections for this condition. The use of iontophoresis with topical preparations for the treatment of plantar fasciitis has been analyzed by several high-quality studies (level I/II evidence). In a prospective, randomized trial, 36 patients with plantar fasciitis were randomized to iontophoresis with either dexamethasone or placebo for six treatments over two weeks as part of multimodality therapy. At the conclusion of treatment (two weeks), a significant difference in Maryland Foot Scores was found in favor of the dexamethasone group; no difference was found, however, at  one month. 25 More recently, a randomized, double-blinded, placebocontrolled trial of 31 patients who received iontophoresis with placebo, dexamethasone, or acetic acid in addition to multimodality therapy found improvements in morning pain, morning stiffness, and average pain at the conclusion of six treatments (two weeks) in both treatment groups compared with placebo. At four weeks, however, only those treated with iontophoresis using topical acetic acid maintained improvements in morning stiffness compared with placebo.26 Besides minor skin irritation, few complications have been reported with the use of iontophoresis, although the determination of an accurate

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complication rate has been limited by the relatively small sample sizes in these studies. In our experience, iontophoresis, when added to multimodality therapy, may provide a small transient benefit, potentially with less risk of complications compared with steroid injection.

Extracorporeal Shock-wave Therapy Extracorporeal shock-wave therapy (ESWT), or orthotripsy, involves the generation of acoustic waves that dissipate energy at the interface of two substances with differing acoustic impedance. Based on the energy density of the applied impulse, ESWT is classified as low-energy (0.2mJ/mm2). High-energy ESWT requires regional or general anesthesia and is typically performed in a single setting. Low-energy ESWT usually does not require anesthesia, and is typically performed as a series of weekly treatments. The therapeutic mechanism behind ESWT is unknown, but the localized injury is thought to result in localized inflammation, neovascularization, and repair of the injured and degenerative plantar fascia, or perhaps in alterations in peripheral nerve function by modulation of the production of bioactive substances.27 Conflicting data exist with regard to the efficacy of this modality. In a randomized controlled trial involving patients with plantar fasciitis of at least six weeks’ duration, 160 participants were randomized to receive either three weekly low-energy ESWT or three sham treatments. Both groups showed improvement at six and 12 weeks in various functional outcome measures, although no significant difference between groups was found (level I evidence).28 Participants in this study had short durations of symptoms (as short as six weeks), and might have been expected to improve with or without treatment, limiting our ability to generalize this study’s findings to more longstanding or recalcitrant cases. In an observer-blinded, randomized, controlled study with 112 patients with plantar fasciitis of at least  six months’ duration, participants received three once-weekly low-energy ESWT sessions with either 10 (sham treatment) or 1,000 pulses per session. Patients were evaluated at six months with regard to satisfaction, pain, and function, all of which strongly favored the treatment group by a statistically significant margin. After five years, the authors noted that 58% of the placebo group had undergone surgical release, compared with 13% in the treatment group (level I evidence).29 Finally, a recent prospective multicenter randomized controlled trial enrolled 293 patients with recalcitrant plantar fasciitis of over six months’ duration to undergo either single high-energy ESWT or sham treatment. Statistically significant improvements in pain and function were found at three months in the treatment group compared with controls (level I evidence).30 Despite a growing body of work regarding the efficacy of ESWT for the treatment of plantar fasciitis, including several recent reviews and meta-analyses,31,32 interpretation of these studies has been limited somewhat by the heterogeneity of study methodology and patient populations. Moreover, as a practical matter, few insurance plans in our area cover this modality at this time, and most of our patients consider the out-of-pocket costs prohibitively expensive. Nonetheless, the best available evidence suggests that both low- and high-energy ESWT are safe and may be a reasonable alternative to surgery in patients with

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long-standing (over  six months) recalcitrant plantar fasciitis who have failed standard non-operative management.

Operative Treatment Operative treatment for plantar fasciitis is reserved for chronic, recalcitrant cases where multimodality non-operative treatment has failed. Surgical options include endoscopic or open partial plantar fascia release and open complete plantar fascia release. Adjunctive treatments to address associated pathology include tarsal tunnel release or decompression of the first branch of the lateral plantar nerve (FBLPN), which may be performed when nerve entrapment is suspected. Recently, some surgeons have begun performing gastrocnemius recession, either alone or in conjunction with the above procedures, for patients with plantar fasciitis and a gastocnemius equinus contracture. Although a few early retrospective reports have been encouraging,33,34 level I and level II evidence studies demonstrating the efficacy of this strategy are lacking. Overall, there is a paucity of high-quality studies defining the optimal method of operative intervention for patients with recalcitrant plantar fasciitis. Open partial plantar fascia release, with release of the FBLPN, was popularized by a classic paper by Baxter and Thigpen in which 32 of 34 patients from an athletic population with recalcitrant plantar heel pain achieved good results after undergoing release of the FBLPN and partial plantar fascia release as necessary to achieve adequate nerve decompression (level IV evidence).35 It is unclear whether partial plantar fascia release effectively reduces tension at the proximal plantar fascia origin, however, and others have found less favorable results with this approach. In fact, in more recent studies over half of patients had persistent functional limitations after surgery.36,37 Some have suggested that an association between nerve entrapment and biomechanical incompetence of the proximal plantar fascia may exist in some patients with chronic recalcitrant plantar fasciitis and heel pain.18 In these patients, an operative strategy that involves a proximal and distal tarsal tunnel release with FBLPN decompression, as well as a complete plantar fascia release, may be most effective. In a retrospective study detailing the above procedure, 75% of patients were satisfied and had improved functional outcomes after undergoing surgery.38 The authors stressed the importance of  four weeks of postoperative weight-bearing restrictions and the use of a pre-operatively molded orthotic for at least six months following surgery. It is important to recognize that partial or complete surgical release of the plantar fascia may have significant biomechanical and structural consequences. A recent finite element analysis of partial and complete plantar fascia release has suggested that release of greater than 40% of the plantar fascia results in increased strain in the plantar ligaments and elevated load bearing of the central metatarsals and lateral midfoot, potentially explaining the frequent observation of dorsolateral midfoot pain following plantar fascia release.39,40 Evidence from several case series and retrospective reviews (level III and IV evidence) suggests that endoscopic partial plantar fascia may offer patients a faster recovery than traditional open techniques.41–43 Although these studies have shown some optimistic results in terms of

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Foot pain relief and functional outcome scores, they have been limited by their short follow-up (generally one year or less), retrospective designs, and small sample sizes. Poorer results have been noted in these studies in patients with symptom duration longer than two years and in patients with worker compensation claims.40 Endoscopic techniques lack the ability to address related pathology (e.g. entrapment of the FBLPN) and carry the risk of iatrogenic nerve injury due to poor visualization compared with open techniques. Operative management for plantar fasciitis remains reserved for chronic, recalcitrant cases, although many of these patients clearly benefit from surgery. Additional high-quality studies are needed to determine which surgical techniques provide the greatest benefit in terms of pain relief and functional improvement, with the fastest recovery and the lowest risk of complications.

Summary Plantar fasciitis affects approximately two million people in the US and is  the most common cause of plantar heel pain.1 Fortunately, most cases are self-limited and resolution of symptoms with non-operative measures can be expected in 90% of patients within 10 months. The goal of non-operative treatment is to relieve pain, improve function, and shorten the duration of symptoms. Based on our experience and the available literature, including recent level I and level II evidence studies, our initial approach to these patients involves multimodality nonoperative treatment with an emphasis on PFSS. Those who fail an

1. 2. 3. 4. 5. 6. 7. 8. 9.

Riddle DL, Schappert SM, Foot Ankle Int, 2004;25:303–10. Wright JG, et al., J Bone Joint Surg Am, 2003;85:1–3. Cheng HY, et al., J Biomech, 2008;41:1937–44. Benjamin M, et al., J Anat, 2006;208:471–90. Abreu MR, et al., Skeletal Radiol, 2003;32:13–21. Williams PL, et al., Foot Ankle, 1987;7:345–9. Alshami AM, et al., Foot Ankle Int, 2007;28:499–505. Alshami AM, et al., Man Ther, 2008;13:103–11. Levy JC, et al., Foot Ankle Int, 2006;27:427–30.

10. Karabay N, et al., J Foot Ankle Surg, 2007;46:442–6. 11. Narvaez JA, et al., Radiographics, 2000;20:333–52. 12. American Orthopaedic Foot and Ankle Society, Position Statement: Endoscopic and Open Heel Surgery, aofas.org, 2010. 13. DiGiovanni BF, et al., J Bone Joint Surg, 2003;85A:1270–77. 14. DiGiovanni BF, et al., J Bone Joint Surg, 2006;88A:1775–81. 15. Flanigan RM, et al., Foot Ankle Int, 2007;28:815–22.

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optimized course of non-operative treatment, generally after at least nine to 12 months, may benefit from surgery. Associated pathologies, including nerve entrapment and/or gastrocnemius equinus contracture, may be especially common in this population, however, and must be recognized and addressed surgically in order to obtain the best results for these patients. n

Benedict F DiGiovanni, MD, is Director of the Foot and Ankle Fellowship Program at the University of Rochester Medical Center Orthopaedics and Director of the Musculoskeletal Curriculum at the University of Rochester School of Medicine. He is a board-certified orthopaedic surgeon and Associate Professor of Orthopaedics. He is an active researcher, with a particular interest in plantar fasciitis and chronic ankle pain in the athlete, and has authored numerous medical articles and orthopaedic surgery textbook chapters. Dr DiGiovanni received his MD from Case Western Reserve University School of Medicine, where he also completed a residency in orthopaedic surgery and research. He then completed foot and ankle fellowships at the Medical College of Wisconsin and the American Sports Medicine Institute in Birmingham, Alabama.

Andrew M Moore, MD, is an Orthopaedic Foot and Ankle Fellow at the University of Rochester Medical Center. He has authored several scientific manuscripts and book chapters on conditions of the foot and ankle. He will be starting private practice this year in Bowling Green, KY. Dr Moore attended medical school at the University of North Carolina before completing his residency training in orthopaedic surgery at the University of Michigan.

16. Powell M, et al., Foot Ankle Int, 1998;19:10–18. 17. Roos E, et al., Foot Ankle Int, 2006;27:606–11. 18. Schippert DW, et al., Current Orthopaedic Practice, 2009;20:130–35. 19. Landorf KB, et al., Arch Intern Med, 2006;166:1305–10. 20. Pfeffer G, et al., Foot Ankle Int, 1999;20:214–21. 21. Donley BG, et al., Foot Ankle Int, 2007;28:20–23. 22. Crawford F, et al., Rheumatology, 1999;38:974–7. 23. Acevado JI, Beskin JL, Foot Ankle Int, 1998;19:91–71.

31. Rompe JD, et al., Br Med Bull, 2007;81–82:183–208. 32. Thomson CE, et al., BMC Medical Discord, 2005;6:19. 33. Chilvers M, Rocco JJ, Manoli A, II, Gastrocnemius recession for chronic plantar fasciitis, Annual Summer meeting of the American Orthopaedic Foot and Ankle Society, July 2007, Toronto, Canada. 34. Maskill JD, et al., Foot Ankle Int, 2010;31:19–23. 35. Baxter DE, Thigpen CM, Foot Ankle, 1984;5:16–25. 36. Davies MS, et al., Foot Ankle Int, 1999;20:803–7.

Sellman JR, Foot Ankle Int, 1994;15:376–81. Gudeman SD, et al., Am J Sports Med, 1997;25:312–16. Osborne HR, Allison GT,Br J Sports Med, 2006;40:545–9. Hausdorf J, et al., Brain Res, 2008;1207:96–101. Buchbinder R, et al., JAMA, 2002;288(11):1364–72. Rompe JD, et al., J Bone Joint Surg Am, 2002;84-A(3): 335–41. 30. Ogden JA, et al., J Bone Joint Surg Am, 2004;86-A(10):2216–28.

37. 38. 39. 40. 41. 42. 43.

24. 25. 26. 27. 28. 29.

Conflitti JM, Tarquinio TA, Foot Ankle Int, 2004;25:482–7. DiGiovanni BF, et al., Tech Foot Ankle Surg, 2003;2:254–61. Cheung JT, et al., Foot Ankle Int, 2006;27:125–32. Brugh AM, et al., J Foot Ankle Surg, 2002;41(6):365–71. Bazaz R, Ferkel RD, Foot Ankle Int, 2007;28:549–56. Hogan KA, et al., Foot Ankle Int, 2004;25:875–81. Tomczak RL, Haverstock BD, J Foot Ankle Surg, 1995;34(3):305–11.

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