A RADIOLOGICAL
APPROACH IAN
From
The because
subtalar their
joint
the
and
Department
eversion
and
presents
are
its
generally
adduction and the calcaneum
SUBTALAR
JOINT
ENGLAND
Manchester
Royal
radiological
technical
Infirmary
abnormalities
are
often
overlooked
difficulties.
thought
the foot, but it is at the talo-calcaneo-navicular (Wood Jones 1949). Active movements at this Hence inversion, “Movement of
THE
MANCHESTER,
of Radiology,
is complex,
demonstration
Inversion
ISHERWOOD,
TO
to be carried joint that are usually
level
out
at the
transverse
joint
of
most of these movements occur combined with ankle movement.
flexion under
occur together as do eversion, abduction and extension. the talus is essential to inversion and eversion and fixation of the calcaneum will for all practicable purposes these
prevent of this
fore
movements.”
(Inkster
1938.)
Abnormalities
region, whether congenital or acquired, a considerable effect on the function
foot. The object
and
have theremobility
of the
of this
paper
approach
to the demonstration
examples
of
the
is to
abnormalities
a radiographic
suggest
of this
illustrated
region,
by
exposed.
ANATOMY
The facets These joints
subtalar
separated The Lii
anterior A drawing
is formed
by an inter-articular posterior joint has
about 40 degrees to the complex but generally FIG.
1
same
of the upper
of the facets of and the sulcus calcanei
calcaneum.
joint
The
the calcaneum
three
surface
separated
and direction
middle and
its
mid-line curved
joint relation
ligament (Smith long axis set
sets
of
of the talus. and posterior are frequently 1894). obliquely
at
of the foot. Its contour is convexly upwards. The
facets of the calcaneum to the axis of the foot,
have the but their
curvature tends to be concave. Across the contiguous surfaces of the calcaneum and talus are grooves-the sulcus ca!canei and sulcus tali-which complete the canalis tarsi. This tunnel opens at its anterior
joint
are demonstrated. end into the interosseous about which
by three
on the ca!caneum and plantar surface may be termed the anterior, middle (Fig. 1). The anterior and middle joints
wide bay of the sinus tarsi. The talo-calcaneal ligament occupies gliding movements may occur.
canal the
is occupied sinus tarsi
by fat and small vessels. and represents a strong
The axis
RADIOGRAPHY
To involves particularly
establish multiple for
Palmer
a logical
(1948)
commented
lateral view from below and the end of the sinus tarsi. 566
radiographic
projections. injuries of the
Several calcaneum. on
the
posteriorly Slomann
approach projections difficulties
to
a joint
have
been
of
of demonstration
to give a clear view of the (1926) and Holland (1928) THE
this
suggested
JOURNAL
complexity
obviously
by previous
and
suggested
posterior facet had previously OF
BONE
AND
authors, an
oblique
as it reaches emphasised JOINT
SURGERY
A
the An
importance view
Anthonsen (1953)
this
for
projection
the
towards
the
with
Normal
to
for
toes,
produce
but
comparative
foot
tilts
an
attempt
reproduction
VOL.
K
43B,
to NO.
in
ray
the
together
it is felt
the film. Several oblique
from
tube
two
central
medial
demonstrate
lateral
3, AUGUST
on
that the difficult. and the
1961
tilts,
the 25
SUBTALAR
567
JOINT
many
caudally
to on
a
the
tubes.
angulation
middle lateral
facets.
30
degrees
dorsi-ventrally
below the medial malleolus It has not been found possible
just
film.
FIG. 4 Figure 3-Medial oblique axial projection. factors are given on page 568.
The
foot
together
joint projections
She
coalition.
commended by Warrick and middle facets. The technique and
point
projection. Radiographic
x-ray
double The
highly and
posterior
degrees
position
lateral projection.
oblique joint
THE
projection
directed
being
FIG. 3 joint. Figure 2-Oblique 4-Lateral oblique axial
these
this,
described an oblique value in demonstrating
involves
the
dorsiflexed
subtalar Figure
counter
its
TO
view in the diagnosis of calcaneo-navicular in some centres (Chambers 1950).
an
is
(1943)
Bremner
APPROACH
oblique lateral standard procedure
of
oblique
RADIOLOGICAL
suggested
facet
position
with is also
can
foot
at
were
suggested
that
the
limb
be adjusted
positioning
its
greatest by Clark
be rotated
to
makes distance (1956) medially
in
568
I. ISHERWOOD
45 degrees
and the tube
tilted
40 degrees,
30 degrees
or 10 degrees.
be rotated
laterally 45 degrees with a tube tilt of 12 to In a busy orthopaedic department also undertaking
available
Alternatively,
18 degrees. accident
work
the limb
it is of value
may
to have
a routine
procedure that can be applied to both static and traumatic lesions arising at the subta!ar joint. It should be a method applicable to immobilised patients and to painful stiff feet. It should also be a method which can be used with any x-ray tube and with as little wastage
of time
as possible.
An
attempt
has
demonstrating all sections of the subtalar A disarticulated skeleton foot with establish a resilient joint oval periphery of all three ajoint
is with
tangentially on the complex
its contiguous to each
film confirmed curved surface
forward
Oblique
made
The
surfaces
between
in profile.
superimposition
The
of the
economic
talus
the
method
and
of
calcaneum
to
fixed in turn to the method of viewing
ray
was
margins
therefore of the
directed
oval
Since the posterior of it at right angles.
were also technique
as an approach to the subtalar joint. (oblique lateral) to demonstrate film and anterior
central
the joint. two views
wire markers in position By this experimental
on the 1 inch
the
opposite
dorso-plantar
border of the foot is placed is centred 1 inch below and
an
Wire markers were The most advantageous
the profile projection of it is advantageous to obtain foot with authors.
to establish
rubber
was radiographed. of the calcaneum.
articular
joint.
of the disarticulated described by previous put
space facets
been
joint. foam
marker
joint has Radiographs
a
obtained in all the projections the following projections are
anterior
joint
the sole inclined 45 degrees to the lateral malleolus.
(Fig.
2).
to the
film.
The
inner
The
tube
Medial oblique axial to demonstrate the middle joint and also to give a tangential view of the convexity of the posterior joint (Fig. 3). The foot is dorsiflexed and when possible inverted, the position being maintained by a broad bandage held by the seated patient. The limb is
rotated
medially
axially,
tilted
the lateral adduction
60 degrees
easily
the
towards
malleolus. and flexion,
foot the
rested
head
an end-on of placing the “
reproduced
centred
completes by an
view of the sustentaculum
“
by a fixed
on a 30 degrees
and
Inversion, which can be maintained
This projection gives the added advantages being
and
10 degrees
angulation
broad
bandage. the
foot
The rested
limb
on
is laterally
canalis tali
of the
rotated
a 30 degrees
and but
axial projections it is suggested
above
should Multiplane
have
that
may be necessary when interest
be routine. tomography
and
(see
degrees, tube
tube
is directed
1 inch
anterior
of broad
have
view but has detail and of
below). (Fig. 4). The foot by asymmetrical flexing
the
is directed
knee
axially,
the tuber-joint subtalarjoint
been
to
inversion, bandage.
is dorsiflexed pull on the
when
necessary,
tilted
10 degrees
medial malleolus. The tube direction radiographic factors used are 60-65 film. Standard views of the tarsus
to demonstrate is directed to the
stereoscopy
and
as in Anthonsen’s to the film for bone
in profile maintained
The
towards the head and centred 1 inch below the may be fixed for both oblique axial views. The and 50 mAs, at 36 inches using Ilfex non-screen
tarsi close
tube
60
wedge.
The
below
the composite movement asymmetrical pull on the
Lateral oblique axial to demonstrate the posteriorjoint and when possible everted, the position again being and
wedge.
1 inch
the
investigated
and tilt kilovolts in lateral
angle or other features projections described
to a limited
extent
and
potentialities. ABNORMALITIES
The projections
following were
abnormalities
abnormalities-Two
spastic flat Talo-calcaneal
foot” aspect
OF
been
THE
SUBTALAR
demonstrated
JOINT
by
oblique
views
when
standard
inadequate.
Congenital
posterior
have groups
of structural
anomalies
have a direct relation to the subtalar bridge-The bridge may be osseous, of
the
sustentaculum
tali
with
the
which
may
produce
a “peroneal
or
fibrous,
uniting
joint. cartilaginous talus.
Movement TIlE JOURNAL
of the joint OF
BONE
AND
the
is impeded JOINT
SURGERY
A
and
inversion oblique be
may
APPROACH
is impossible. Symptoms because late sequelae may
is valuable medial
RADIOLOGICAL
the
axial only
view.
when
feature
TO
THE
SUBTALAR
569
JOINT
often do not occur until adolescence, but early be reduced. The bony bar may be demonstrated
Narrowing the fusion
of the middle is cartilaginous
joint
space (Fig.
is also
usually
diagnosis in the
present
and
5).
FIG. 5 Talo-calcaneal bridge. The bridge demonstrated in the medial oblique axial view unites the posterior aspect of the middle joint with the talus. The joint space is narrowed.
FIG.
Calcaneo-navicular calcaneo-navicular
Calcaneo-naricular
bridge-A
developmental
factors
develop. tarsal
joint
fusion
Symptoms is more
is best
It has presence
voi. 43 B,
of
NO.
of this vulnerable
in the suggested
these 3,
anomalies
AUGUST
early
type of differentiation
fusion
1961
may occur mesenchyme.
of
coalition are often found earlier, to stress than the subtalar joint
oblique lateral view (Fig. 6). that many feet show some
seen
been
similar
in the
6
bridge. A pseudarthrosis is present in the bridge, demonstrated in the oblique lateral view.
has
been
overlooked
degree
because
due
probably to A pseudarthrosis
similar may
because, it is thought, the in childhood (Jack 1954). of valgus
of the
deformity
difficulty
and
of visualisation
that
midThis the on
570
I. ISHERWOOD
routine
radiographs
(Webster
lateral aspect of the congenital anomalies including at the
Jack
and
(1954),
however,
joint
of whatever
midtarsal
Roberts
head of the (Harris and
talus Beath
1951,
Harris
as representing origin.
Spur
1955).
has been considered 1948). It has been the
effects
formation
significant described
of long
It is to be emphasised
standing
the dorso-
on
of the by some
presence authorities
valgus
therefore
that
of
deformity
this
sign
when
on the dorso-lateral surface of the talus seen in the lateral projection. A subsequent medial oblique axial radiograph demonstrated a talo-calcaneal bridge.
formation
standard
Fracture
of the calcaneum.
I
seen
a routine
of
joint
in
view
(Fig. 7). Extra-articular
8 and 9he medial ob..que axial and the lateraloblique axial demonstrate the subtalar joint to be intact.
the
arthrodesis
foot
is an
of the
indication
subtalar
joint
for
by introducing
tarsi has been employed in the correction of some Maintenance of the graft in position post-operatively
cases
essential. while the
for
The foot
medial still
is
oblique in
axial
view
is valuable
further
investigation bone
of paralytic as an effective confirming
of the grafts
into
subtalar the
sinus
flat foot (Grice 1952). block to eversion is
this
and
may
OF
BONE
AND
be employed
plaster. THE
JOURNAL
JOINT
SURGERY
A
Traumatic or
RADIOLOGICAL
lesions-Fractures
may
Warrick
and
Bremner
lateral portion fragment
of
the
(1953)
the
of
the
of
joint,
the subtalar
involve
by
TO
calcaneum
the
when
compression
FIG.
fractures
compression
of identifying be depressed
may
571
JOINT
crack
shearing
importance
which
facet
secondary
SUBTALAR
be simple
in
the
articular
THE
may
particularly
emphasised
posterior
calcaneum
APPROACH
the
fracture
(Figs. 8 and 9) type of fracture.
the position into the main runs
obliquely
of the lateral across
10
Fracture of the calcaneum. Depression of the posterior articular facet with a horizontal split of the tuberosity demonstrated by the medial oblique axial view.
of the subtalar joint. Involvement of the anterior compartment demonstrated by the oblique lateral view (note involvement of the calcaneo-cuboid joint). Oblique axial views showed the remainder of the subtalar joint to be relatively spared. Tuberculosis
the
posterior
lateral
facet.
portion
may
The
be
facet
may
continuous
with
be demonstrated by the Many fractures of the calcaneum varying functional disability.
VOL.
43 B,
features
can
NO.
3,
AUGUST
1961
be
depressed
with media!
the
with
the
tuberosity and
underlying
which
lateral
oblique
with severe joint involvement
It
seems
to
be
of
some
is split axial
bone
or
the
horizontally.
depressed These
views (Fig. 10). may lead to bony ankylosis importance prognostically,
572
I.
however,
to
demonstrate
anticipated
when
severe
14).
(Fig.
Arthritis. may
the
Tuberculous
be produced
any joint articular
Gout
in the
involvement margins
(Fig.
arthritis
but
early
ISLIERWOOD
because
have
been
11)-In
stages
degenerative disrupted.
tuberculous
the
infection
change
arthritis
may
may
Traumatic
complete
be limited
frequently
arthritis
be be
may
disorganisation
to part
of the joint
and
of the subtalar joint. Involvement of the middle compartment demonstrated in the medial oblique axial projection.
FIG.
13
Rheumatoid compartment oblique
arthritis. Almost complete loss of joint space in the middle of the subtalar joint is demonstrated by the medial axial view. The posterior compartment is relatively spared. (Note involvement of the talo-navicular joint.)
be
demonstrable by oblique views. Clinical differentiation (Fig. 12)-Urate deposits in gout may be demonstrated before any major arthritic change has developed. Rheumatoid Gout
mainly deformity
involving the small joints by involvement of the
distally, subtalar
at this stage may be difficult. in relation to the subtalar joint arthritis (Fig. 13)-Although
rheumatoid arthritis may joint. Standard views are THE
JOURNAL
produce usually OF
BONE
a rigid confined AND
JOINT
valgus to the SURGERY
A
forefoot are
and
foot.
proximal
demonstrable.
secondary joint
early
RADIOLOGI(’AL
Early
may
be seen
space
clearly
SUBTALAR
is often only
confined
in oblique
and
in
It is capable
573
JOINT
Erosions
l4)-Osteoarthritis
or to trauma.
of the joint
therefore
TIlL
TO
be overlooked.
(Fig.
deformity
narrowing will
changes
Osteoarthritis
to structural
and
APPROACh
the
joint
of producing
to one axial
space
subtalar
a stiff
or two
narrowing
joint
may
and
compartments
be
painful of the
views.
FIG. 14 Gross osteoarthritis after injury. Several tarsaljoints are involved,
particularly the posterior demonstrated in the
compartment
lateral
FIG.
of
oblique
the
axial
subtalar
joint
projection.
15
Osteitis deformans of the calcaneum. Secondary narrowing the middle compartment of the subtalar joint, demonstrated the medial oblique axial projection.
Local
bone
change
in
disease-Many the
subtalar
other
conditions,
joint-for
example,
primarily osteitis
affecting deformans
bone, (Fig.
in in
may
produce
secondary
15).
SUMMARY
The
subtalar
joint
projections
are
described
VOL.
43 B,
NO.
3,
AUGUST
is not
easy
including 1961
to visualise medial
and
by lateral
standard oblique
radiographic axial
views
methods. to demonstrate
Several the
574
I. ISHERWOOD
three compartments of the joint. It is suggested that when visualisation is required these views should be routine. Various conditions affecting the subtalar joint and their demonstration axial
views
are
of the
subtalar
by these
joint oblique
discussed.
I should
like to thank Dr E. Duff Gray, Director of the Department of Radiology, and Mr D. Lloyd Griffiths, of the Department of Orthopaedic Surgery, Manchester Royal Infirmary, for their valuable advice and encouragement. I am indebted to Dr R. 0. W. Ollerenshaw and the Department of Medical Illustration of the Manchester Royal Infirmary for the preparation of the prints, and to Mr R. A. H. Neave for the drawing in Figure 1. I should alsolike toacknowledge theenthusiasticcooperation ofMiss E. McRae, Senior Radiographer
Director
in the
Orthopaedic
X-ray
Department.
REFERENCES W.
ANTHONSEN,
Particularly
(1943) Regarding
A. E., and
BREMNER,
: An
Oblique
Projection
Intra-articular
WARRICK,
for
Fracture
C. K. (1951)
Roentgen
of the
: Fractures
Examination
Calcaneus.
Acta
of the Calcaneus.
of
the
Radiologica,
Journal
ofthe
British
Journal
Talo-calcanean 24, 306. Faculty
Joint,
of Radiologists,
2, 235. C. H. (1950):
CHAMBERS,
Congenital
Anomalies
of the Tarsal
Navicular.
of Radiology,
N.S.
23,
580. K. C. (1956): Positioning in Radiography. Seventh edition. Ilford Limited. London: Wm. Heinemann (Medical Books) Ltd. GRICE, D. S. (1952): An Extra-articular Arthrodesis of the Subastragalar Joint for Correction of Paralytic Flat Feet in Children. Journal ofBone and Joint Surgery, 34-A, 927. HARRIS, R. I. (1955): Rigid Valgus Foot due to Talocalcanea! Bridge. Journal of Bone and Joint Surgery, 37-A, 169. HARRIS, R. I., and BEATH, T. (1 948) : Etiology of Peroneal Spastic Flat Foot. Journal of Bone and Joi,it Surgery, 30-B, 624. HOLLAND, C. Thurstan (1928): The Accessory Bones of the Foot. In The Robert Jones Birthday Volume, p. 157. CLARK,
London:
Humphry
Milford
Oxford
University
Press.
R. G. (1938): Inversion and Eversion ofthe Foot and the Transverse Tarsal Joint. Journal of Anatomy, 72, 612. JACK, E. A. (1954): Bone Anomalies of the Tarsus in Relation to “ Peroneal Spastic Flat Foot.” Journal of Bone and Joint Surgery, 36-B, 530. JONES, F. Wood (1949): Structure and Function as Seen in the Foot. Second edition. London: Bailli#{234}re,Tindall INKSTER,
and
Cox.
I. (1948): The Mechanism and Treatment of Fractures of the Calcaneus. Journal of Bone and Joint 30-A, 2. SLOMANN, H. C. (1926): On the Demonstration and Analysis of Calcaneo-Navicular Coalition by Roentgen Examination. Ada Radiologica, 5, 304. SMITH, E. Barclay (1894): The Astragalo-Calcaneo-Navicular Joint. Journal of Anatomy and Physiology, 30,390. WARRICK, C. K., and BREMNER, A. E. (1953): Fractures of the Calcaneum. Journal of Bone and Joint Surgery, 35-B, 33. WEBSTER, F. S., and ROBERTS, W. M. (1951): Tarsal Anomalies and Peroneal Spastic Flatfoot. Journal of the American Medical Association. 146, 1,099. PALMER,
Surgery,
THE
JOURNAL
OF
BONE
AND
JOINT
SURGERY
