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Special Radiographic Projections of the Foot and Ankle:
A Primer for Residents and Fellows
Arlene J. Richardson, MD, Michel A. Scott, RT(R), Gregory S. Stacy, MD
University of Chicago Medical Center, Department of Radiology, Chicago, IL USA
ABSTRACT
Purpose: The ACR-SPR-SSR Practice Guideline
for the Performance of Radiography of the
Extremities provides recommendations for “routine”
radiographic views of the foot and ankle. The
purpose of this exhibit is to present non-routine or
“special” radiographic projections of the foot and
ankle that are often useful for diagnosing
abnormalities not readily seen on routine views.
Methods Used: Cases of “routine” and “special”
radiographic views of the foot and ankle were
collected from the imaging database at our
institution, and are presented here.
Results: Following a brief review of anatomy
depicted on routine radiography of the foot and
ankle, as well as the limitations of these
projections, a variety of special radiographic views
of the foot and ankle commonly used at our
institution are discussed. Pictorial examples of
normal anatomy depicted on these non-routine
views, as well as examples of abnormalities better
seen on these projections, are provided.
Conclusions: Radiography is the mainstay of foot
and ankle imaging. Standard projections are
recommended for initial evaluation, with
supplemental special views obtained to evaluate a
specific problem or condition. These optional
radiographic views of the foot and ankle can allow
a more detailed and cost-effective evaluation of
various pathologic conditions, which may be
incompletely assessed by standard radiographic
views.
INTRODUCTION
Foot and ankle disorders are common, yet
potentially complex, representing a wide range of
conditions. Indications for radiography of the foot
and ankle include, but are not limited to, pain,
trauma, arthropathies, infections, neoplasms,
systemic diseases, congenital and developmental
disorders, and preoperative or postoperative
evaluation and follow-up. Routine radiographic
views of the foot and ankle are typically the first
line of imaging.
• Routine radiographs of the ANKLE include AP, lateral and oblique views. The
preferred oblique view is obtained with 15-20o of medial rotation of the leg and foot –
the “mortise” view, which provides the best assessment of mortise congruity and the
talar dome. An oblique view obtained with 45o of medial rotation of the leg and foot
is used in some practices.
AP view (left) allows evaluation of distal tibia and
fibula, tibiotalar joint, proximal talus, and peripheral
borders of tarsals. Note overlap of distal fibula and
anterior tibial tubercle, as well as overlap of distal
fibula and talus, limiting evaluation of tibiofibular and
talofibular articulations, but implying ligamentous
integrity.
Lateral view (right) allows evaluation of tibiotalar
joint congruity and potential effusion, talocalcaneal
relationships, and 5th metatarsal base. Medial and
lateral talar domes are superimposed, and fibula
overlies posterior half of tibia.
Medial oblique “mortise” view with 15-20o of
medial rotation (left) allows evaluation of congruity
of entire ankle mortise (arrows) with no overlap of
distal fibula with anterior tibial tubercle or talus.
Medial oblique view with 45o of medial rotation
(right) allows evaluation of lateral malleolus and
distal tibiofibular joint (arrow); distal tibia and fibula
are often superimposed with talus.
• REVERSE OBLIQUE VIEWS
• Obtained with LATERAL (rather than medial) rotation; also called “LATERAL or
EXTERNAL OBLIQUE” VIEWS
• For the reverse (lateral) oblique view of the FOOT, the patient is positioned
supine with the leg and foot rotated laterally until the plantar surface of foot
forms an angle of 30 degrees to image receptor (elevation of the medial aspect
of the foot). The central ray is directed to the 3rd metatarsal base,
perpendicular to the image receptor.
• This view can better demonstrate the bones of the medial aspect of the
midfoot, which typically overlap one another on routine views, and can
reveal subtle fractures of the 1st metatarsal base, medial cuneiform,
navicular, and accessory navicular, as well as assess 1st TMT joint fusion
following surgery.
Lateral view (left) allows
assessment of talus and
calcaneus, and their
relationship to midfoot and
ankle joint, although bones
of forefoot and midfoot
partially obscured due to
overlap.
•
•
•
•
AP (far left), medial
oblique (left) and lateral
(top) foot radiographs
show no fracture.
Reverse/lateral oblique
radiograph (right)
shows navicular fracture
(arrow).
• For the reverse (lateral) oblique view of the ANKLE, the leg and foot are
rotated 45o laterally. This view, which can add information about the medial
malleolus, is used infrequently.
• Routine radiographs of the FOOT include AP, lateral and oblique views. The oblique
view is obtained with 30-40o of medial rotation of the foot (elevation of the lateral
aspect of the foot with a radiolucent support block)
AP view (left) allows evaluation of the phalanges,
metatarsals, and tarsal bones anterior to the talus,
although the second through fifth metatarsal bases,
lateral cuneiform and cuboid, and anterior process of
calcaneus are partially obscured due to overlap (red
box).
Oblique view (right) allows better assessment of
lateral tarsometatarsal articulations by reducing
overlap (green box). Note stress fracture (arrow).
“SPECIAL” RADIOGRAPHS OF THE
FOOT AND ANKLE (continued)
“SPECIAL” RADIOGRAPHS OF THE
FOOT AND ANKLE
ROUTINE RADIOGRAPHS OF
THE FOOT AND ANKLE
Normal Broden I view
(above). Note
visualization of subtalar
joint (arrow) and
calcaneus.
•
Reverse/lateral oblique
radiograph of ankle shows medial
malleolus (arrows) and superior
aspect of calcaneus.
•
•
•
SESAMOID VIEW
A tangential projection of the sesamoid bones at the 1st MTP joint can be
performed with the patient prone and the foot dorsiflexed so that the ball of the foot
is perpendicular to the horizontal plane; the toes are then dorsiflexed at the MTP
joints and placed on the image receptor (the Lewis Method). Alternatively, the
patient may be seated on the table with the back of the heel placed on the image
receptor and the plantar surface of the foot 75o relative to the horizontal; the
patient then uses a band to dorsiflex his/her toes. In either case, the central ray is
directed tangential to the ball of the foot and perpendicular to the image receptor.
This view can allow visualization of both sesamoids without overlap with other
bones, and hence can be useful for diagnosing fractures, arthritis, osteonecrosis
and osteomyelitis.
The Causton method involves placing the medial aspect of the foot on the image
receptor, and then directing the central ray to the 1st MTP joint at and angle of 40o
toward the heel; there is slight overlap of the sesamoids using this projection.
Routine AP, oblique and lateral radiographs of
the ankle show tri-malleolar “SER-IV” fractures
(arrows) and bullet fragment in lateral soft
tissues.
Tangential
projection
(above) showing
normal sesamoid
bones.
•
•
•
Routine AP, lateral
and oblique
radiographs of the
foot demonstrate
typical changes of
Charcot arthropathy
(arrows) of the
midfoot.
Axial radiographs of the right and left calcaneus
show abnormal slanting of the middle facet of
the left subtalar joint (arrow) suggestive of
nonosseous coalition, confirmed on CT
• Routine radiographs of the OS CALCIS include lateral and axial views. The axial
view can be obtained with the patient supine and the posterior aspect of the dorsiflexed
heel placed on the image receptor, with the central ray angled 40o cephalad from the
long axis of the foot (plantodorsal projection); alternatively, it can be obtained with the
patient prone and the sole of the foot placed on the image receptor perpendicular to
the tabletop with the central ray angled 40-45o caudally (dorsoplantar projection). A
similar dorsoplantar projection with the patient standing on the image receptor was
described by Harris and Beath in 1948. While the plantodorsal projection is often used
in trauma, the dorsoplantar projection typically better shows the subtalar articulations.
•
Lateral view (left) shows calcaneus in
profile and allows assessment of talus,
subtalar joint, and calcaneocuboid joint.
Axial view (right) obtained using
dorsoplantar projection shows posterior
and medial facets of subtalar joint
(arrows), as well as alignment of heel
Lateral view (left) shows slight
deformity of posterior tuberosity of
calcaneus and “double density”,
concerning for fracture.
Axial view (right) obtained using
plantodorsal projection better shows
fracture of posterior tuberosity (arrow),
without evidence of extension to
subtalar joint.
CANALE VIEW
The CANALE VIEW is a talar neck view described by Canale and Kelly for fracture
evaluation.
It is obtained by placing the ankle in maximal equinus with the foot pronated and
internally rotated 450. The x-ray beam is centered on the talar neck and angled 15
degrees cephalad.
Minimally displaced fractures of the talar neck may assume varus deformity at the
fracture site that is not appreciated on routine radiographs. The Canale view is
helpful for fracture detection as well as assessing degree of fracture angulation
and displacement and adequacy of reduction
Normal Canale view
(above). The talar
neck is well
visualized.
•
•
AP and lateral views (top left and center) show mild
irregularity of lateral sesamoid bone, which is obscured by
overlying bone. Tangential projection (top right) better
shows increased density of lateral sesamoid indicating
osteonecrosis (arrow).
Lateromedial oblique radiograph of calcaneus
shows calcaneal tuberosity (arrow), cuboid and
sinus tarsus
The REVERSE BRODEN (BRODEN II) is also useful for evaluating the
subtalar joint, as well as the posterior talus, which is seen in profile
• The foot is positioned as for an AP ankle radiograph and dorsiflexed,
but rotated 45o laterally. The central ray is angled cephalad 15o to a
point 2cm anterior and caudal to the medial malleolus.
Normal
Broden II
view (above).
Note that
posterior
process of the
talus is seen in
profile.
•
Posterior talar
fracture fixation
(arrow) is better
assesed on Broden
II view (right), in
comparison with the
lateral ankle
radiograph (left).
The ISHERWOOD method consists of radiographs of the subtalar joint
obtained with medial rotation of the foot (for the anterior facet), medial
rotation of the ankle (for the middle facet) and lateral rotation of the ankle
(for the posterior facet).
Normal Isherwood projections with
medial rotation of the foot (left),
medial rotation of the ankle (center)
and lateral rotation of the ankle
(right), demonstrating anterior, middle
and posterior facets, respectively.
•
•
WEIGHT-BEARING AND STRESS VIEWS
WEIGHT-BEARING VIEWS are used to assess structural changes such as
joint narrowing, subluxation and malalignment. Although considered
“special” views, some practices recommend weight-bearing radiographs for
all evaluations unless clinically contraindicated.
Lateral view of AP view of
foot obtained
foot obtained with
with patient
patient weightweight-bearing bearing (left) better
(top) better
demonstrates
demonstrates
LisFranc disruption
pes planus.
(arrow).
•
STRESS VIEWS may be obtained to assess ligamentous stability in
patients with suspected soft tissue injuries.
Medial oblique (left) and lateral (central) radiographs
show orthopaedic fixation of talus, but poor
visualization of talar neck fracture. Canale view (right)
better demonstrates talar neck fracture (arrow).
LATEROMEDIAL OBLIQUE PROJECTION OF CALCANEUS
This weight-bearing view of the calcaneus is obtained with the patient standing on
the image receptor. The central ray is directed to the lateral malleolus
lateromedially at a caudal angle of 45o.
Broden I radiographs in 3 different patients
showing intra-articular calcaneaus fracture (left),
subtalar dislocation (center) and subtalar fusion
(right).
Posterior talar fracture
is clearly seen on
Broden II view (right),
and not as well
visualized on lateral
ankle radiograph (left).
• Routine radiographs of the TOES also include AP, lateral and oblique views.
Enhanced detail and reduced superimposition of toes allows for better assessment of
phalanges and interphalangeal joints than with routine foot radiographs
AP, lateral and
oblique foot
radiographs (left,
cropped to show
forefoot) in kickboxer
with great toe pain
show no abnormality.
Great toe
radiographs (right) of
same patient show
avulsion fracture
(arrow).
SUBTALAR JOINT VIEWS
The complex anatomy of the subtalar joint presents a diagnostic challenge
that can require special views and advanced imaging for full evaluation.
A variety of projections for depiction of the subtalar joint and hindfoot have
been described, including the Broden and Isherwood methods.
At our institution, the BRODEN views are ordered most frequently.
• The foot is positioned as for an AP ankle radiograph, then dorsiflexed
and rotated 45o medially. In our practice, the central ray is angled
cephalad 20o to a point 2-3cm anterior and caudal to the lateral
malleolus; views at multiple angles (10-40o) can also be obtained.
• Allows visualization of the posterior facet of the subtalar joint and used
to evaluate intra-articular calcaneus fractures and subtalar fusions.
AP ankle radiographs without (left) and
with (right) eversion stress demonstrate
abnormal widening of medial joint
space indicating deltoid ligament tear
and unstable tibiotalar joint
AP foot radiograph without
stress (right) shows equivocal
LisFranc disruption. Radiograph
with stress (right) confirms TMT
joint offset and LisFranc injury
REFERENCES
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ACR–SPR–SSR Practice Guideline for the Performance of Radiography of the Extremities
Bontrager, KL. Textbook of radiographic positioning and related anatomy, 5th ed. 2001, Mosby,
Inc.
Slovenkai MP. Radiography of the ankle. Foot Ankle Clin 2000;5:149-164
Surgery of the Foot and Ankle, 8th Edition. Coughlin, Mann, Saltzman
George Koulouris, MD, and William B. Morrison, MD. Foot and Ankle Disorders: Radiographic
Signs. Seminars in Roentgenology Volume 40, Issue 4 , Pages 358-379, October 2005
Merrill’s Atlas of Radiographic Positioning and Procedures, 12th Edition. Frank, Long, Smith
R. Harris and T. Beath. Etiology of Peroneal Spastic Flat Foot. Journal of Bone and Joint
Surgery. June 1948