This document provides an overview of ankle and foot anatomy, imaging, and common injuries. It describes: 1) The bones and joints of the ankle and foot, including the tibiotalar, subtalar, and tarsometatarsal joints. 2) Common ankle and foot injuries like fractures of the distal tibia and fibula, talus, and calcaneus. As well as ligament tears and dislocations. 3) Imaging techniques used to evaluate the ankle and foot, including standard radiographs, stress views, and arthrography. Key anatomical angles and measurements are also outlined.

1. Ankle and Foot
Dr. Tarique Ajij
JR, Department of Radio – Diagnosis,
Medical College, Kolkata

2. Anatomy
 tibiotalar and distal tibio-fibular
articulations (syndesmotic joint)
 talocalcaneal (subtalar) articulation

3. Anatomy

4. Anatomy
 foot is divided into three distinct
sections:
 Hindfoot
 Midfoot
 forefoot

5. Anatomy

6. Anatomy

7. Anatomy

8. Movements
 Adduction: medial deviation of the forefoot
 Abduction: lateral deviation of the forefoot,
motions occurring in the tarsometatarsal
(Lisfranc) joint
 adduction of the heel: inversion of the
calcaneus
 abduction of the heel: eversion of the
calcaneus
motions occurring in the subtalar joint
 Plantar flexion: caudad (downward) foot
motion
 Dorsiflexion: cephalad (upward) foot motion
motions occurring in the ankle (tibiotalar) joint

9. Movements
 Supination:
 Adduction & inversion of the forefoot
(motion in the tarsometatarsal and
midtarsal joints)
 inversion of the heel (motion in subtalar
joint)
 slight plantar flexion of the ankle
(tibiotalar) joint
 Pronation:
 abduction and eversion of the forefoot
(motion in the tarsometatarsal and
midtarsal joints)
 eversion of the heel (motion in the
subtalar joint)
 slight dorsiflexion (or dorsal extension)
of the ankle

10. Movements
Varus and valgus should not be used to describe motion
but should be reserved for the description of ankle or foot
position in case of deformity

11. Imaging of Ankle: Xray
AP View

12. Imaging of Ankle: Xray
MortiseView:15Internalrotation

13. Imaging of Ankle: Xray
Lateral View

14. Imaging of Ankle: Xray
Internal oblique view: 35 Internal rotation

15. Imaging of Ankle: Xray
External oblique view: 45 external rotation

16. Imaging of Ankle: Xray
degree of talar
tilt
Interpretation
< 5 Normal
5 – 15 May be
abnormal
15 – 25 S/O lig. injury
> 25 Always
abnormal
Inversion stress view

17. Imaging of Ankle: Xray
Anterior-draw stress
degree
transposition
Interpretation
< 5 mm Normal
5 – 10 mm May be
abnormal
> 10 mm Always
abnormal

18. Imaging of Ankle: Xray
Dorsoplantar View

19. Imaging of Ankle: Xray
Lateral view

20. Imaging of Ankle: Xray
Lateral view
 Boehler angle: determined by the intersection
of a line
 (a) drawn from the posterosuperior margin
of the calcaneal tuberosity (bursal
projection) through the tip of the posterior
facet of the subtalar joint, and a second line
 (b) drawn from the tip of the posterior facet
through the superior margin of the anterior
process of the calcaneus.
Normally, this angle ranges between 20 and 40
degrees.
 Calcaneal pitch is described by the
intersection of a line drawn tangentially to
the inferior surface of the calcaneus and one
drawn along the plantar surface of the foot.

21. Imaging of Ankle: Xray
 angle of Gissane: The greater values
suggest a fracture of the posterior
facet of the subtalar joint

22. Imaging of Ankle: Xray
Dorsi-plantar oblique (DPO)

23. Imaging of Ankle: Xray
Harris-Beath view

24. Imaging of Ankle: Xray
Broden view

25. Imaging of Ankle: Xray
Tangential view

26. Imaging of Ankle: Arthography
 Single contrast:
 Ligament injury
 OCD
 Osteo-cartilaginous bodies
localization
 Chondral and osteochondral fractures
 Double contrast:
 articular cartilage

27. Imaging of Ankle: Tenography
 evaluating tendon tears, particularly
tears of the Achilles tendon, peroneus
longus and brevis, tibialis posterior,
flexor digitorum longus, and flexor
hallucis longus
 Tear is indicated by the extravasation
of contrast agent from the tendon
sheath, abrupt termination of the
contrast-filled tendon sheath, or leak
of contrast into the adjoining
articulations
flexor hallucis longus
peroneus longus and brevis

28. Trauma : overview
 10% of all fractures  Bone
 Ligaments
 Tendons
 Muscle
 Neurovascular bundle

29. Trauma : overview
 type of fracture (Kleiger)
 position of the foot
 the direction and intensity of the
applied force
 the resistance of the structures
 history taking and clinical examination
 radiologic examination (site and
extent of injury)
 types of ankle trauma:
 inversion injuries
 eversion injuries
 complicated by internal or external
rotation, hyperflexion or
hyperextension, and vertical
compression forces

30. Trauma : overview
 Modes of injury:
 direct trauma (blow or a fall from a
height)
 indirect forces (abnormal stress or
strain of muscles or tendons)

31. Trauma : overview

32. Trauma : overview

33. Trauma : overview

34. Fractures About the Ankle Joint
 classified by the anatomic structure
involved

35. Fractures of Distal Tibia and Fibula

36. Fractures of Distal Tibia and Fibula

37. Fractures of Distal Tibia and Fibula

38. Fractures of Distal Tibia and Fibula

39. Fractures of Distal Tibia and Fibula

40. Fractures of Distal Tibia and Fibula

41. Fractures of the Distal Tibia: Pilon #
 Pilon (Pylon) Fracture when it involves
the tibio-talar articulation
 predominant force is vertical
compression

42. Pilon #
 associated fracture of the distal fibula,
talus, and subluxation in the ankle joint
 severe damage to the soft-tissue sleeve
of the distal leg
 confused with trimalleolar fractures
 Look for:
 the presence of profound comminution
of the distal tibia,
 intraarticular extension of tibial fracture
through the dome of the plafond
 usual association of fracture of the talus
 usual preservation of tibiofibular
syndesmosis

43. Pilon #

44.  Müller's widely accepted classification
of pilon fractures divides these injuries
into three groups, depending on the
displacement of the fragments and
the incongruity of the joint

45. Tillaux Fracture
 ankle fracture resulting from
abduction and external-rotation injury
 avulsion of the lateral margin of the
distal tibia
 fracture line is vertical and extends
from the distal articular surface of the
tibia upward to the lateral cortex

46. Tillaux Fracture

47. Juvenile Tillaux fracture,
 is actually a Salter-Harris type III

48. Tillaux Fracture
 If the fracture fragment is laterally
displaced more than 2 mm or if there
is an irregularity of the articular
surface of the distal tibia (a step-off),
then surgical rather than conservative
treatment is indicated
 CT is the best method

49. Tillaux Fracture

50. Wagstaffe-LeFort fracture
 the medial portion of the fibula
becomes detached and the anterior
tibiofibular ligament remains intact

52. Triplanar (Marmor-Lynn) Fracture
 Fractures involving the lateral aspect
of the distal tibial epiphysis
 complicated by extension of the
fracture line into two other planes
 MOI: plantar flexion and external
rotation
 combination of the juvenile Tillaux
fracture and a Salter-Harris type II
fracture
 should not be mistaken for a Salter-
Harris type IV fracture

53. Triplanar (Marmor-Lynn) Fracture

54. Triplanar (Marmor-Lynn) Fracture

55. Salter-Harris type IV fracture
 No horizontal # line

56. Triplanar (Marmor-Lynn) Fracture

57. Triplanar (Marmor-Lynn) Fracture

58. Fractures of the Fibula: Pott Fracture
 It is now recognized that this type of
fracture usually occurs as a result of
the disruption of the tibiofibular
syndesmosis.

59. Fractures of the Fibula: Dupuytren
Fracture
 fracture of the fibula occurring 2 to 7
cm above the distal tibiofibular
syndesmosis and including disruption
of the medial collateral ligament
 associated tear of the syndesmosis
leads to ankle instability

60. Fractures of the Fibula: Maisonneuve
Fracture
 eversion-type injury
 # in the proximal half of the bone
 tibiofibular syndesmosis is always
disrupted
 either tear of the tibiofibular ligament
or fracture of the medial malleolus is
also present
 The more proximal the location of the
fibular fracture, the more is the
damage to the interosseous
membrane

61. Fractures of the Fibula: Maisonneuve
Fracture

62. Weber classification
 based on the level of fibular fracture
and therefore on the type of
syndesmotic ligament injury
 The higher the fibular fracture, the
more extensive the damage to the
tibiofibular ligaments and, thus, the
greater the risk of ankle instability

63. Weber A

64. Weber B

65. Weber C

66. Fractures of the Foot: Fractures of the
Calcaneus
 sustained in falls from heights
 sometimes called lover's fractures
 whether the fracture line involves the
subtalar joint
 Determination of the Boehler angle
and angle of Gissane

67. Fractures of the Calcaneus

68. Fractures of the Calcaneus

69. Fractures of the Calcaneus

70. Fractures of the Calcaneus
 fall from a height, a radiograph of the
thoracolumbar spine is essential
 associated finding of compression
fracture of one of the vertebral bodies

71. Stress fracture of the calcaneus
 Sclerotic # line
 No H/O trauma

72. Stress fracture of the calcaneus

73. Fractures of the talus
 neck of the talus is the most
vulnerable site
 forced dorsiflexion of the foot
 dislocation in the subtalar and
talonavicular joints
 Hawkins classification

74. Fractures of the talus

75. Fractures of the talus

76. Osteochondritis Dissecans of the Talus
 Cause: familial, trauma, ischemia
 lesion involving the talar dome
 located in the anterolateral (inversion
and dorsiflexion injury) or in the
posteromedial (plantar flexion and
external rotation) aspect of the talar
dome
 associated with lesions of the lateral
collateral ligament complex

77. Osteochondritis Dissecans of the Talus
 Berndt and Harty classification of OCD
lesions:
 Stage I: Subchondral lesion with no
involvement of the subchondral bone
plate or articular cartilage
 Stage II: Partial osteochondral lesion
with one side of the lesion remaining
attached to the adjacent bone
 Stage III: Completely separated
osteochondral lesion with the
fragment in situ
 Stage IV: Completely separated
osteochondral lesion with a displaced
fragment

78. Osteochondritis Dissecans of the Talus

79. Osteochondritis Dissecans of the Talus

80. Navicular Fractures

81. Jones Fracture
 avulsion fracture of the base of the
fifth metatarsal
 inversion stress placed on the
peroneus brevis tendon

82. Jones Fracture

83. Dislocations in the Foot

84. Dislocations in the Subtalar Joint
 Two major types
 peritalar dislocation of the foot
 total dislocation of the talus

85. Peritalar dislocation of the foot
 simultaneous dislocations in the
talocalcaneal and talonavicular joints
with normal maintenance of the
tibiotalar relationship
 Four subtypes: medial, lateral,
posterior, and anterior
 look for associated fractures,
particularly of both malleoli, the
articular margin of the talus, and the
navicular and fifth metatarsal bones

86. Total Talar Dislocation
 complete disruption of both the ankle
(tibiotalar) and the subtalar joints
 serious of all talar injuries
 complicated by osteonecrosis

87. Tarsometatarsal Dislocation
 Also termed Lisfranc fracture-dislocation
 most common dislocation in the foot
 association with various types of
fractures (# base of the second MT)
 two basic forms of injury:
 homolateral— dislocation of the first to
the fifth metatarsal
 divergent—lateral displacement of the
second to the fifth metatarsals with
medial or dorsal shift of the first
metatarsal
 most common complications of ankle
and foot fractures are nonunion and
posttraumatic arthritis

88. Tarsometatarsal Dislocation

89. Tarsometatarsal Dislocation

90. Tarsometatarsal Dislocation

91. Posttraumatic Joint Effusion
 assessed on the lateral radiograph of
the ankle by
 appearance of focal soft-tissue density
anteriorly to the joint
 Encroachment of the Kager triangle,
also known as pre-Achilles fat pad

92. Soft Tissue Injury

93. Tear of the Medial Collateral Ligament
 eversion force
 associated with a tear of the
tibiofibular ligament and lateral
subluxation of the talus
 Xray: lateral shift of the talus in the
absence of a spiral fracture of the
fibula

94. Ligaments: Medial Ankle Ligaments
 It has several components—
 Tibiotalar
 Tibiocalcaneal
 talonavicular
 the spring ligament (between the
sustentaculum of the calcaneus and
navicular bone)

95. Tibiotalar Tear

96. Spring Ligament – part of deltoid

97. Torn Spring Ligament

98. Tear of the Lateral Collateral Ligament
 Xray: No fibular # with inversion-
stress film of the ankle by an increase
in talar tilt to 15 degrees or more

99. Tear of the Lateral Collateral Ligament:
Arthography
• Leakage around the tip of the fibula
indicates a tear of the anterior talofibular
ligament
• filling of the peroneal tendon sheath
indicates a tear of the calcaneofibular
ligament
• leak of contrast into the tibiofibular
syndesmosis indicates a tear of the distal
anterior tibiofibular ligament
• Filling of the posterior facet of the subtalar
joint indicates a tear of the posterior
talofibular ligament

100. Tear of the Lateral Collateral Ligament:
Arthography

101. Lateral Collateral Ligament
 Superior Group
 Anterior and posterior tibiofi bular
ligaments
Seen at top of ankle joint on axial images
 Inferior Group
 Anterior to posterior: Anterior
talofibular, posterior talofibular, (Seen
on axial images at level of malleolar
fossa of fibula) calcaneofibular
(coronal)

102. Lateral Collateral Ligament

103. Tibiofibular ligament: tear

104. Lateral ankle ligament tears
association with sinus tarsi syndrome, anterolateral impingement syndrome, and
longitudinal split tears of the peroneus brevis tendon

105. Muscles and Tendons

106. Tendon Ruptures: Tendo Achilles
 severe tenderness at the tendon's
insertion
 limitation of plantar flexion
 Avulsion of this tendon from its
calcaneal insertion

107. Tendon Ruptures: Tendo Achilles

108. Tendon Ruptures: Tendo Achilles

109. Tendon Ruptures: Tendo Achilles

110. Tendon Ruptures: Posterior Tibial

111. Tendon Ruptures: Posterior Tibial

112. Tendons

113. Achilles
 largest tendon in the body
 confluence of tendons from the
gastrocnemius and the soleus muscles
 No tendon sheath - it cannot have changes of
tenosynovitis, but only of paratendinitis
 paratenon present on the dorsal, medial, and
lateral aspects of the Achilles tendon that
allows smooth gliding of the tendon
 flat or concave anterior margin on axial
images
 posterior margin of the Achilles has a convex
contour
 7 mm AP diameter
 anterior and posterior margins are parallel on
true sagittal images through the tendon

114. Achilles and Plantaris
 plantaris tendon lying anteromedial to
the Achilles tendon, which inserts
onto the Achilles tendon, or to the
posterior calcaneus, or to the flexor
retinaculum

115. Achilles tendon

116. Haglund’s deformity
 AKA “pump bumps”
 ill-fi tting footwear, and from
inflmmatory arthropathies
 triad of retro-Achilles bursitis,
retrocalcaneal bursitis, and thickening
of the distal Achilles tendon

117. Posterior Tibial Tendon
 attaches to the medial navicular bone,
the three cuneiforms, and the bases of
the first to fourth metatarsals
 attachment to the navicular bone is
generally the only portion of the
attachment identified by MRI
 Normal high signal on T2 near the
attachment

118. Posterior Tibial Tendon

119. Posterior Tibial Tendon
 loss of the longitudinal arch, resulting
in a flat foot deformity
 Middle-aged or older women and
rheumatoid arthritis
 Tears of this tendon also are
associated with the sinus tarsi
syndrome and degenerative joint
disease of the posterior subtalar joint
and abnormal spring ligament

120. Flexor Hallucis Longus
 attach to the base of the distal
phalanx of the great toe
 synovial tendon sheath is in
communication with the ankle joint in
20% of individuals
 fluid surrounding the tendon is
common and may have no
significance if an ankle joint effusion
also is present

121. Flexor Hallucis Longus
 Focal, asymmetric pooling of fluid
within the tendon sheath is indicative
of stenosing tenosynovitis
 associated with the os trigonum
syndrome

122. Flexor Hallucis Longus

123. Peroneal Tendons
 share a common tendon sheath
proximally, but have separate sheaths
distally
 Brevis anterior or medial to longus
 brevis eventually attaches to the base of
the fifth metatarsal
 longus has a broad-based insertion on
the plantar surface of the base of the
firrst metatarsal and medial cuneiform,
after traversing the plantar aspect of the
foot
 Flat is acceptable (for many things), but
if the brevis becomes C-shaped, it is
considered abnormal.

124. Peroneal Tendons
 Calcaneal fractures can be associated
with entrapment of the peroneal
tendons between bone fragments,
tendon tears, tendon displacement, or
impingement on tendons by fracture
fragments

125. Peroneus brevis splits
 Asymptomatic in old age
 Pain and swelling in youngs
 Peroneus brevis longitudinal tears occur
during dorsiflexion, when the brevis tendon is
wedged between the lateral malleolus and
the peroneus longus tendon
 torn or lax superior peroneal retinaculum, a
flat or convex (rather than normal concave)
posterior aspect of the lateral malleolus, low-
lying peroneus brevis muscle belly (extending
to the tip of the lateral malleolus), and the
presence of an accessory muscle called the
peroneus quartus.
 A sharp posterolateral fibular spur may be
seen

126. peroneus quartus

127. Peroneal tendons: dislocation.
 shallow or hypoplastic retromalleolar
groove of the fibula may predispose
to subluxation of the peroneal
tendons
 inversion injury with plantar flexion

128. Anterior tibial tendon: tear

129. Nerves

130. Tarsal Tunnel Anatomy
 a fibro-osseous tunnel located on the
medial side of the ankle and hindfoot

131. Tarsal Tunnel Syndrome

132. Tarsal Tunnel Syndrome

133. Tarsal Tunnel Syndrome

134. Tarsal Tunnel Syndrome

135. Tarsal Tunnel Syndrome
 Even if MRI shows no abnormality affecting the tarsal tunnel, it is valuable
because it means that surgery is not indicated and would not benefit the patient

136. Morton Neuroma
 previously was believed to represent a
neoplastic process of the nerve
 but now is thought to be secondary to
chronic nerve entrapment
 with subsequent perineural fibrosis,
neural degeneration, and often
adjacent intermetatarsal bursitis
 around the plantar digital nerve of the
second or third intermetatarsal space

137. Morton Neuroma

138. Morton Neuroma

139. Morton Neuroma

140. Morton Neuroma
 Treatment may consist of modifcation
of footwear, percutaneous neurolysis,
surgical release by dividing the
transverse metatarsal ligament, or
excision.

141. Baxter Neuropathy
 caused by compression of the inferior
calcaneal nerve (known as Baxter
nerve)
 entrapment by a hypertrophied
abductor hallucis muscle particularly
in runners, compression by inferior
calcaneal enthesophyte/ thickened
plantar fascia, and stretching
secondary to a hypermobile pronated
foot
 MR imaging findings include
denervation edema or fatty atrophy of
the abductor digiti minimi muscle

142. Painful Soft-Tissue Abnormalities

143. Sinus Tarsi Anatomy
 The sinus tarsi, or tarsal sinus, is a
cone-shaped space formed between
the calcaneus and talus
 The narrow end of the cone is located
medially, whereas the large end is
located laterally, beneath the lateral
malleolus.
 The sinus tarsi contains fat, several
ligaments, neurovascular structures,
and portions of the joint capsule of
the posterior subtalar joint
 Nerve endings in the sinus tarsi are
important for proprioception of the
hindfoot
 slips from the lateral extensor
retinaculum;
 cervical ligament
 most medial is the interosseous
ligament

144. Sinus Tarsi Syndrome

145. Sinus Tarsi Syndrome

146. Sinus Tarsi Syndrome

147. Sinus Tarsi Syndrome
 If only part of the fat has been
replaced, it is unlikely to be associated
with the sinus tarsi syndrome
 One must not confuse a large joint
effusion of the ankle or subtalar joint
extending into the sinus tarsi as
evidence of an abnormal sinus tarsi.
 The fat in the sinus tarsi can be
obscured by fl uid or hemorrhage in
acute ankle sprains; a diagnosis of
sinus tarsi syndrome should not be
made in the setting of acute trauma.
 Alawys correlate clinically that patient
has symptoms
 Treated by steroid injection,
reconstruction of the ligaments of the
sinus tarsi, surgical débridement, and,
rarely, triple arthrodesis

148. Anterolateral Impingement Syndrome

149. Anterolateral Impingement Syndrome

150. Anterolateral Impingement Syndrome

151. Painful Accessory Navicular Bone
Syndrome
 os navicularis or os tibiale externum is
present in about 10% of the
population
 It is united to the medial aspect of the
navicular bone with a synchondrosis
 Athletic activities may lead to
inflammation of this accessory ossicle
and associated tendinosis of the
posterior tibialis tendon.
 MRI is the imaging technique of
choice to demonstrate the signal
alterations of the bone and the
morphologic changes of the posterior
tibialis tendon

152. Painful Os Peroneum Syndrome
 os peroneum is a sesamoid bone
located within the peroneus longus
tendon just proximal to the entrance of
the tendon into the cuboid tunnel
 Pain in the lateral aspect of the foot
 acute or chronic fracture or diastasis of a
bipartite or multipartite os peroneum;
tendinosis or tear of the peroneus
longus tendon or presence of a large
peroneal tubercle in the lateral aspect of
the calcaneus
 MRI can demonstrate fragmentation
and edema of the os peroneum and
associated pathology of the peroneus
longus tendon

153. Plantar Fasciitis
 plantar fascia originates on the plantar
aspect of the calcaneus
 It extends over the intrinsic muscles of
the foot, the abductor digiti minimi
(lateral cord), the flexor digitorum brevis
(central cord), and the abductor hallucis
(medial cord)
 present with pain in the plantar aspect
of the heel on weight bearing
 Predisposing factors include obesity,
enthesopathy, pes cavus, systemic
disease (inflammatory arthritis), overuse,
altered gait, and trauma

154. Plantar Fasciitis

155. BONE ABNORMALITIES: Tarsal
Coalition
 6% of the population
 failure of proper segmentation of the
tarsal bones
 acquired secondary to rheumatoid
arthritis or trauma
 The two most common types are
calcaneonavicular & talocalcaneal
 limited motion in the subtalar joint >
increased stresses elsewhere in the
tarsus > spasm of the peroneals and
extensors, with an associated flatfoot
deformity

156. Tarsal Coalition
 Coalitions may be osseous, fibrous,
cartilaginous, or a combination.
 MRI:
 presence of the coalition, which type,
and how extensive it is
 surrounding structures for
impingement by the hypertrophic
bony mass, such as displacement of
the tibialis posterior and flexor hallucis
longus tendons in the tarsal tunnel
 Secondary degenerative joint disease
in the posterior subtalar joint is
common and can be documented with
MRI.
 MRI shows narrowing and irregularity,
or osseous fusion, of the middle facet
of the subtalar joint. The angle of this
joint is often abnormal, with a
coalition being directed inferiorly

157. Tarsal Coalition

158. Tarsal Coalition

159. Os Trigonum Syndrome
 Clinical: Repetitive plantar flexion (ballet,
basketball, kicking football, running on hills)
 Etiology: Os trigonum/trigonal process and flexor
hallucis tendon trapped between calcaneus and
tibia
 Pathology: Marrow edema/fracture of trigonal
process or synchondrosis of os trigonum; flexor
hallucis longus irritation (stenosing
tenosynovitis)
 MRI:
 T1W: Low signal in marrow of posterior talus
 T2W:
 High signal marrow in talus
 High signal fracture of synchondrosis, os trigonum
 Focal, loculated high signal fluid around flexor
hallucis (stenosing tenosynovitis)
 Loose bodies

160. Os Trigonum Syndrome

161. Accessory Navicular
 Large cornuate process of navicular or
accessory navicular bone
 Marrow edema, overlying bursitis,
degenerative joint disease between
accessory bone and navicular,
associated posterior tibial tendon
tears
 T2W MRI shows high signal of all
abnormalities
 much higher incidence of posterior
tibial tendon tears in the presence of
an accessory navicular bone, caused
by altered stresses

162. Hallux Sesamoids
 Located in flexor hallucis brevis tendons
at first metatarsal head
 Abnormalities: Acute or stress fractures,
osteonecrosis, infection, sesamoiditis
(inflammation), dislocation, participate
in inflammatory and degenerative joint
disease
 MRI is sensitive, but nonspecific; low
signal on medial sesamoid more likely
to be traumatic in origin; lateral
sesamoid is more likely osteonecrosis
 Turf Toe: hyperdorsifl exion of the fi rst
metatarsophalangeal joint with
disruption of the plantar capsular tissues

163. Hallux Sesamoids

164. Osteonecrosis of the Foot and Ankle
 Navicular (unrecognized fracture)
 Metatarsal heads, especially second
and third (repetitive stresses,
highheeled shoes)
 Talar dome (talar neck fracture)
 Lateral hallux sesamoid
 serpiginous low signal intensity lines
creating a geographic pattern, or
diffuse low signal on T1W images that
may or may not become higher signal
on T2W images

165. Osseous Tumors
 malignant primary and metastatic
lesions are rare

168. BONE MARROW EDEMA SYNDROME
 young patients
 generalized pain not attributable to
any source
 Bilateral, selflimiting
 Patchy increased T2 signal is often
seen scattered about multiple bones
in the foot and ankle

169. Soft tissue tumors
 MRI is useful to confirm the
presence and extent of a soft
tissue mass, and to
determine the precise
anatomic location, which aids
in surgery; in some cases, the
appearance is specific for a
particular lesion

170. Plantar Fibromatosis
 benign proliferation of fi brous tissue along
the plantar aspect of the foot
 arising in the plantar fascia
 manifests as a nodule on the sole of the foot,
usually medial in location
 Painless
 a single or multiple small nodular thickenings
of the plantar fascia that appear as low to
intermediate signal intensity on T1W and
T2W sequences, enhance with intravenous
gadolinium
 The upper margin: infiltrative and can grow
into the deeper compartments of the foot,
the lower margin usually is well defined and
outlined by the subcutaneous fat
 lesions often are not biopsied or surgically
removed, unless they are large.

171. Synovial Sarcoma
 most common
 extraarticular soft tissue mass
 Xray : scattered calcifications,
infiltrative and destroy adjacent bone
 well defined and benign by imaging
criteria, sometimes creating a pressure
erosion on adjacent bone
 MRI: Necrosis and haemorrhage &
T1C+ heterogeneous enhancement

172. Accessory soleus
 anatomic normal variant
 pain
 secondary to ischemia that occurs
during exercise as a form of a
localized compartment syndrome
 may compress the posterior tibial
nerve in the tarsal tunnel, resulting in
tarsal tunnel syndrome

173. Peroneus quartus muscles
 lies in the posterior ankle, just anterior and
lateral to the Achilles tendon
 Asymptomatic or lateral ankle pain and ankle
joint instability
 predispose to subluxation of the peroneal
tendons because of its mass effect within the
confi ned space created by the peroneal
retinaculum and subsequent stretching and
laxity of the retinaculum
 manifest as a mass or be an incidental finding
on MRI
 The peroneus quartus runs posteromedial to
the peroneus longus and brevis tendons and
usually attaches to the retrotrochlear
eminence on the calcaneus, which is located
posterior to the peroneal tubercle.

174. Accessory flexor digitorum longus
 compressive neuropathy of the
posterior tibial nerve in the tarsal
tunnel
 The tendon from another accessory
muscle, the peroneocalcaneus
internus, runs parallel to a portion of
the fl exor hallucis longus tendon and
may simulate a longitudinal split of
that tendon

175. Pressure Lesions
 Usually asymptomatic, occasionally
painful
 Probably related to adventitious bursa
formation
 Common locations:
 Plantar to first and fifth metatarsal heads
 Plantar to plantar fascia at calcaneal
tuberosity
 Posterior to distal Achilles (bursa of
Achilles tendon)
 Medial to metatarsal head in hallux
valgus
 transfer lesions: after operation, stresses
have been transfer to new site
 MRI: Low signal all sequences, usually
 mimic a soft tissue tumor, especially
before developing cystic changes
 Typical locations, the MRI characteristics
are not entirely typical of a true mass
lesion, and fat often is intermixed

176. Pressure Lesions

177. Diabetic Foot
 multifactorial etiology: small vessel
ischemia, neuropathic arthropathy,
fractures, and infections
 usually have developed a soft tissue
ulcer over a pressure area in the foot
 differentiating osteomyelitis from soft
tissue infection
 Differentiation is difficult clinically, but
is important and affects the therapy
the patient receives, including the
length of antibiotic treatment and the
decision for surgical débridement
 role of imaging:
 detect osteomyelitis or soft tissue
abscesses
 assess the extent
 useful in the planning of any surgical
procedure or biopsy
 MRI to be more cost-effective than
the standard three-phase radionuclide
bone scan and indium-labeled white
blood cell scans
 MRI can detect sinus tracts, cellulitis,
abscesses, and tendon abnormalities.

178. Diabetic Foot

179. Diabetic Foot

180. Diabetic Foot

181. Diabetic Foot

182. Diabetic Foot

183. Foreign bodies
 not radiopaque and cannot be seen
on radiographs.
 Small foreign bodies often migrate
from the site of entry through the skin
to a distant site
 Most foreign bodies are linear and
low signal intensity on T1W and T2W
sequences
 Surrounded by high signal intensity
on T2W sequences

184. Thank
You