Health&Medicine.

1. Dr/ ABD ALLAH NAZEER. MD.
Radiological Film Reading of the Ankle Joint.

2. Disorders of the Achilles Tendon.

3. Disorders of the Achilles Tendon.
Axial T2-weighted MR image with fat suppression shows barbed-wire
appearance of fascicles (curved arrow). Also note partially circumferential
high signal (straight arrow) consistent with small degree of peritendonitis.

5. Sagittal T1-weighted (A) and sagittal short tau inversion recovery (B) MR images show bulbous thickening
(solid straight arrows) of Achilles tendon and that anterior and posterior margins of Achilles tendon are no
longer parallel. No internal signal can be seen. Note normal volume of retrocalcaneal bursa fluid (solid
curved arrow). Incidentally noted is cartilaginous calcaneal navicular coalition (open arrow).

7. Axial T2-weighted fat-suppressed MR image shows extensive thickening
of Achilles tendon with loss of normal concave anterior margin (arrows).

9. Sagittal T1-weighted MR image shows markedly thickened Achilles tendon (white arrows) caused by
rheumatoid arthritis. Also, note findings consistent with retrocalcaneal bursitis (straight black arrow)
and with subtalar joint disease (curved black arrow). Erosion of calcaneus can be seen as well.

11. Gout. Sagittal T1-weighted MR image shows thickening of Achilles tendon (straight arrows) representing
gouty infiltration. Gouty infiltration of anterior tibialis tendon (curved arrow) can also be seen.

13. 55-year-old woman with mucoid degeneration. Sagittal T1-weighted and sagittal short tau
inversion recovery MR images show thickened Achilles tendon with internal signal (arrows).
This signal was nonlinear and interrupted on T2-weighted image (not shown).

17. 58-year-old woman with mucoid degeneration. Sagittal F-short tau inversion recovery image :
inversion time, 150 msec) shows irregular longitudinal mucoid deposit in Achilles tendon (arrows).

19. 8-year-old man with mucoid degeneration. Axial T2-weighted fat-suppressed MR image shows thickened
Achilles tendon (arrows) with multifocal speckled appearance consistent with mucoid degeneration.

21. 47-year-old male runner with peritendonitis. Axial T2-weighted fat-suppressed MR image shows
thin rim of partially circumferential high signal (arrows), which represents mild peritendonitis.
Background mucoid degeneration within tendon and intratendon signal can be seen.

23. 45-year-old man with acute Achilles tendonitis. Fat-suppressed MR image
(TR/TE, 6000/80) shows edema in fat anterior to Achilles tendon (arrows).

25. 45-year-old man with interstitial tear. Sagittal short tau inversion recovery
image (TR/TE, 4000/48; inversion time, 150 msec) shows multiple longitudinal
lines (arrows) inside thickened Achilles tendon consistent with interstitial tear.

27. Achilles interstitial tear. Sagittal PD and PD FS and axial PDFS images reveal areas of T2 fluid signal parallel
to the long axis of the tendon (arrows). Interstitial tears are caused by coalescence of areas of degeneration.

29. Longitudinal area (arrowheads) inside distal
Achilles tendon consistent with insertional
interstitial tear. Small amount of reactive marrow
edema (straight arrow) is seen in calcaneus as well
as excessive retrocalcaneal bursitis (curved arrow).
Partial posterior Achilles tendon tear (black arrow).
Longitudinal interstitial tear (white arrows) and
evidence of underlying hypoxic degeneration with
thickened tendon can also be seen.

31. Partial Achilles tendon rupture. Axial PD and sagittal PD FS and PD
images of a partial rupture of the fibers of the Achilles tendon (arrows).

33. Complete Achilles tendon tear (arrows)
in typical location: 5 cm from its
insertion. Gap is approximately 1 cm.
Completely avulsed Achilles tendon (arrow) with
significant gap because proximal fibers have
been retracted. Fluid can be seen within gap.

35. Complete Achilles tendon rupture. Axial and sagittal PD FS and PD images of
a complete rupture of the Achilles tendon with tendon retraction (arrows).

37. Acute Achilles tendon tear and atrophy. Axial short tau inversion recovery image shows
evidence of edema within soleus muscle (arrows), which is consistent with acute atrophy.

39. 48-year-old man with symptomatic spur. Sagittal T1-weighted (A) and short tau inversion
recovery (B) MR images show subtle edema in posterior calcaneal spur (arrows).

41. MR images show degenerative cyst at posterior calcaneus (arrows) adjacent to thickened
Achilles tendon insertion. Small amount of reactive edema can be seen around cyst.

43. Edema (curved arrows) in Kager's fat pad anterior to Achilles tendon, which is consistent with
acute Achilles tendonitis. Extensive reactive marrow edema (straight arrows) can also be seen.

45. Insertional tendinosis. Sagittal PD FS and PD, and axial PD images of the ankle
revealing a thickened Achilles tendon insertion with increased internal signal (arrows).

47. Axial fast spin-echo MR image shows extensive retrocalcaneal bursitis (solid arrow) with
linear thick signal within Achilles tendon (open arrow) representing insertional tendonitis.

49. Grade 1 soleus muscle strain secondary to an Achilles rupture. Axial FS PD FSE image.

51. Sagittal T1-T2WI MR images show soft-tissue signal displacing fat posterior to thickened Achilles tendon
consistent with retro-Achilles bursitis (open arrow, B). Ill-defined fluid can be seen in retrocalcaneal
bursa, which is consistent with retrocalcaneal bursitis (curved arrows). Edema in enlarged tuberosity
(straight arrows) is seen as well. All these findings are suggestive of Haglund's disease.

53. Haglund’s syndrome. Sagittal PD, sagittal PD FS and axial T2 FS images of the posterior ankle.
Images show an enlarged bursal projection (black arrow), retrocalcaneal bursitis (white arrows),
Achilles insertional tendinosis (orange arrows) and adjacent calcaneal bone marrow edema
pattern (blue arrows), consistent with Haglund’s syndrome. Otherwise known as a “pump
bump”, an enlarged bursal projection or Haglund’s deformity predisposes to this syndrome.

55. Plantaris tendon tear.

56. Peroneal Tendon Injuries.

57. Peroneal Tendon Injuries.
(a) Axial T1-weighted MR image shows a flat to slightly concave retromalleolar groove (black arrow). Note the small,
triangular, labrum-like, low-signal-intensity ridge at the fibular SPR attachment site (white arrow) and the PB muscle
belly (arrowhead). (b) Axial T1-weighted MR image shows a convex retromalleolar groove (black arrow), with an
associated irregular partially torn PB tendon (white arrow). Note the mildly thickened PL tendon (white arrowhead),
a finding consistent with tendinopathy. The SPR is seen superficial to the peroneal tendons (black arrowhead).

59. Enlarged retrotrochlear eminence and peroneal tubercle. (a) Axial T1-weighted MR image shows a mildly
enlarged retrotrochlear eminence (arrow) posterior to the peroneal tendons. (b) Axial T1-weighted MR
image shows a markedly enlarged peroneal tubercle (black arrows). Note the attenuated PB tendon
(white arrow) and mildly thickened PL tendon (arrowhead). The prominent peroneal tubercle measures
more than 5 mm in width (double-headed arrow) relative to the lateral calcaneal cortex.

61. Sagittal T1-weighted MR image of the ankle shows a torn PL and retracted os peroneum (arrowhead)
to the level of the lateral malleolus and a longitudinal split tear of the PB tendon (arrows).

63. Axial fat-saturated T2-weighted MR image shows a markedly distended common peroneal tendon
sheath in the retromalleolar groove with an associated heterogeneous synovial fluid complex (white
arrow), consistent with tenosynovitis. The PB tendon (black arrow) is crescentic, boomerang-shaped,
irregular, moderately thickened, and heterogeneous, findings consistent with severe tendonopathy.
The PL tendon (arrowhead) is minimally thickened, a finding consistent with mild tendonopathy.

65. Axial fat-saturated T2-weighted MR image shows an increased heterogeneous
synovial fluid complex in the peroneal tendon sheath (arrowheads) with associated
linear low-signal-intensity bands, consistent with stenosing tenosynovitis.

67. Axial fat-saturated T2-weighted MR image shows a longitudinal split tear of the PB tendon with an
irregular appearance of two hemitendons (arrows) and the PL tendon (arrowhead) seen deep to
the PB split tendon. The findings are consistent with a Raikin type B intrasheath subluxation.

69. Severe tendonopathy of the PL tendon. (a) Sagittal STIR MR image shows a moderately thickened and irregular PL tendon
at the lateral aspect of the calcaneus (arrowheads), a finding consistent with severe tendonopathy. (b) Axial STIR MR
image shows bone marrow edema along the lateral aspect of the calcaneus (black arrowheads), with
associated PL tendonopathy (white arrowhead) and PB tendonopathy (arrow). A longitudinal split tear of the PB tendon
that extended to the level of the peroneal tubercle was seen in the inframalleolar region (not shown).

71. Longitudinal split tear of the PB tendon. (a) Axial T1-weighted MR image shows a longitudinal split tear of
the PB tendon (white arrows) in the fibular retromalleolar groove, with a grossly normal PL tendon (arrowhead). Note
the accessory peroneus quartus muscle at the posteromedial aspect of the peroneal tendons (black arrow), which is
causing crowding in the retromalleolar groove. (b) Coronal fat-saturated proton-density–weighted MR image shows
the grossly normal PL tendon (arrowhead) between two PB hemitendons (white arrows), with the peroneus quartus
tendon attaching onto the lateral aspect of the calcaneus at the retrotrochlear eminence (black arrows).

73. PL tendon rupture and longitudinal split tear of the PB tendon. (a) Sagittal STIR MR
image of the ankle shows a ruptured PL tendon retracted to the level of the lateral
malleolus (arrowhead) and a longitudinal split tear of the PB tendon (arrows).

75. Longitudinal split tear of the PL tendon, with an associated lateral ankle ligament injury and a type 1 SPR injury. (a) Axial fat-saturated T2-weighted
MR image shows preserved anterior (black arrowhead) and posterior (curved black arrow) syndesmotic ligaments, a flattened PL tendon (white
arrowhead), and a normal PB tendon (straight black arrow). Note the lateral positioning of the peroneal tendons, which invaginate into the small
undersurface SPR tear (white arrow), a finding secondary to a type 1 SPR injury. (b) Axial fat-saturated T2-weighted MR image shows thickening of
the PL tendon (white arrowheads), a finding consistent with tendonopathy, and a normal PB tendon (black arrow). Note the markedly thickened and
irregular anterior (black arrowhead) and posterior (white arrow) talofibular ligaments, findings consistent with a chronic injury or tear. (c) Axial fat-
saturated T2-weighted MR image shows a longitudinal split tear of the PL tendon (arrowheads) and a normal PB tendon (white arrow). Note the
marked thickening and increased signal intensity of the calcaneofibular ligament (black arrow), findings consistent with a tear.

77. Axial T1-weighted MR image at the level of the fibular retromalleolar groove shows an irregular torn SPR with increased
signal intensity and surrounding mild soft-tissue stranding. Note the fleck of bone (black arrowhead) avulsed off of the
lateral malleolus, a finding consistent with a type 3 SPR injury. The peroneal tendons are anteriorly subluxated from the
retromalleolar groove. There is a longitudinal split tear of the PB tendon (arrow). The mild thickening and minimal central
intermediate signal intensity of the PL tendon (white arrowhead) are consistent with tendonopathy.

79. Ganglion cyst at the lateral aspect of the ankle (hindfoot). (a) Axial fat-saturated T2-weighted MR image
shows a well-defined lobulated mass with fluid signal intensity (arrowheads) at the lateral aspect of the
calcaneus, a finding that involves the posterior aspect of the IPR and is consistent with a ganglion cyst.
Note the grossly normal peroneal tendons (arrow). (b) Long-axis US image shows the anechoic ganglion
cyst (arrowheads) and associated posterior acoustic enhancement (arrows). LM = lateral malleolus.

80. Disorders of the Anterior tibialis Tendon.

81. Peroneal Tendonitis / Tendonopathy.
Disorders of the Anterior tibialis Tendon.

83. Peroneal tenosynovitis and longitudinal split tear of the peroneus brevis tendon on the
axial images. A: Circumferential fluid collection is evident within the common peroneal
tendon sheath (arrow), in keeping with tenosynovitis. B: The peroneus brevis tendon has
been divided into two separate subtendons (short arrows) which partially envelope the
peroneus longus tendon (long arrow), in this case of peroneus brevis longitudinal split tear.

85. Tenosynovitis of the combined sheath of the paired peroneal tendons. A (proton density-
weighted axial sequence) and B (T2- weighted fat-suppressed axial sequence): An abnormally
large amount of fluid surrounding the peroneus brevis and longus tendons is shown (arrow).
Thickened synovium is present posteriorly, representing an inflammatory tenosynovitis.

87. MR images of tibialis anterior tendinosis - PD (upper left) and PD with fat saturation
(upper right and lower images). There is thickening and hypersignal of the tibialis
anterior tendon (arrows). There is also a small partial rupture of the tendon, noted
by higher signal intensity in the center of the tendon, similar to fluid signal.

89. Anterior tibial tendon partial rupture. Sagittal PD and PD FS images revealing discontinuity,
thickening and partial retraction of the anterior tibial tendon (arrows) secondary to laceration.

91. Insertional AT tendinosis and partial tear in a 68-year-old man. Short-axis (a) and long-axis (b) fat-
suppressed T2-weighted MR images show increased signal intensity of the AT tendon and longitudinal
splitting (white arrows). Midfoot medial column osteoarthritis demonstrated by productive changes,
marrow edema, and subchondral cysts (black arrows in a) may have predisposed toward the tear.

93. Partial ATT rupture with retraction. Sagittal and axial T2 FS images of the ankle showing partial discontinuity
and retraction of ATT fibers with associated tenosynovitis (arrows). Sagittal and transverse ultrasound images
in the same patient reveal the thickened ATT with partially retracted fibers and tenosynovitis.

95. Complete AT tendon tear in an 83-year-old man. (a) Sagittal T1-weighted MR image shows complete
disruption of the AT tendon with thickening and retraction of the proximal tendon stump (arrow). (b) Axial
fat-saturated T2-weighted MR image shows absence of the tendon (arrow) with surrounding edema.

97. Sagittal T2-weighted MR images show suspected intratendinous gout producing a high-
grade partial AT tendon tear. (a) Marked AT tendon thickening and heterogeneity (arrow)
is seen with suspected intratendinous gout involvement of the ankle joint (*). (b) Multiple
erosions and soft-tissue masses (*) are compatible with suspected gout arthropathy.

99. MR evaluation of tibialis anterior tenosynovitis - There is fluid distension involving the full circumference of the
tibialis anterior tendon (white arrows). Note the normal tendon just proximal to its insertion (yellow arrow).

101. AT tenosynovitis manifesting as a medial midfoot mass in a 42-year-old woman. Long-axis (a) and short-
axis (b) fat-suppressed fluid-sensitive MR images show fluid distending the AT tendon sheath (arrow)
near its distal course over the medial cuneiform and first metatarsal base. The tendon caliber is normal.

103. Tibialis anterior full-thickness tear - on the left, note the radiographic appearance of a soft-tissue
swelling anterior to the distal tibia (white arrows). MR images (T1 weighted and T2 weighted with fat
saturation) show the soft tissue mass to correspond to the retracted tendon (blue arrows) and fluid
(red arrows). There is complete tendon disruption, confirming full-thickness tear.

105. Tibialis anterior subtendinous bursitis - Note fluid distension only partially involving the
tendon (white arrows), in its distal portion, compared to the contralateral normal tendon
(asterisk). This partial involvement is necessary to differentiate from tenosynovitis.

106. Disorders of the Posterior tibialis Tendon.

107. Posterior tibial tendinosis. Axial images (A, B) exhibit moderate thickening
and intermediate signal in the distal posterior tibial tendon (arrows).
Disorders of the Posterior tibialis Tendon.

109. PTT hypertrophy (type 1 tear). Axial PD, coronal and sagittal PD FS images showing a hypertrophied
PTT with heterogenous signal intensity with tenosynovitis, consistent with a type 1 PTT tear. A
normal PTT should be twice the size of the FDL, the abnormal tendon in this case is much larger.

110. Longitudinal split tear of the posterior tibial tendon, creating the “four-tendon sign.” Axial
images (A, B) demonstrate four (instead of three) distinct tendons at the medial side of the
ankle joint. The two most anteromedial tendinous structures (arrows) represent
longitudinal splitting and separation of the original posterior tibial tendon.

111. Longitudinal split tear of the posterior tibial tendon, creating the “four-tendon sign.” Axial
images (A, B) demonstrate four (instead of three) distinct tendons at the medial side of the
ankle joint. The two most anteromedial tendinous structures (arrows) represent
longitudinal splitting and separation of the original posterior tibial tendon.

113. Multifocal split tears of the posterior tibial tendon. Axial images (A, B) demonstrate multiple
linear fluid-like signals within the distal posterior tibial tendon fragments (arrows).

115. Posterior tibial tendon tear in the presence of os naviculare. A: Axial image demonstrates an os
naviculare type II (arrow) with mild bone marrow edema at the posterior tibial tendon
insertion. B: More proximally, the posterior tibial tendon exhibits a longitudinal split tear (arrow).

117. Complete posterior tibial tendon disruption. A: In the axial plane, only fluid is identified at the
expected position of the posterior tibial tendon (arrow). B: Sagittal image shows complete
disruption of the posterior tibial tendon, with associated retraction of the torn fragments (arrows).

119. Retracted PTT tear. Sagittal PD FS images at the medial ankle
showing a type 3 PTT tear, with torn, retracted fibers (arrow).

121. Posterior tibial tenosynovitis. A: Circumferential fluid along the posterior tibial tendon (long arrow) is
indicative of tenosynovitis, in this case of rheumatoid arthritis. Note concurrent peroneus longus
tenosynovitis (short arrow). B: A large fluid collection along with multiple tiny hypointense foci within the
flexor hallucis tendon sheath (arrow) is due to synovial chondromatosis and stenosing tenosynovitis.

122. Disorders of the Flexor Hallucis longus Tendon.

123. Posteromedial ankle pain. Sagittal fast short T1 inversion recovery image shows enlarged
os trigonum tarsi (open arrow) with loculated fluid in flexor hallucis longus tendon sheath
(solid arrow) proximal to os. Flexor hallucis longus tendon was normal (not shown).
Disorders of the Flexor Hallucis longus Tendon.

125. Clawing of great toe after penetrating injury. Axial proton density—weighted MR image shows
scarring (arrow) at myotendinous junction of flexor hallucis longus tendon 1 cm above talar dome.

127. Posterior ankle pain. MR image inferior to A shows enlarged os trigonum tarsi (thin arrow)
with adjacent cystic changes in talus (thick arrow) suggestive of altered biomechanics. There
is abrupt change in amount of fluid in flexor hallucis longus tendon sheath at level of os.

129. FHL tendinosis and tear. Axial PD FS and axial and
sagittal PD images revealing FHL tendinosis at the level
of the sustanaculum tali (white arrows), with distal
degeneration and tearing of the tendon fibers (orange
arrows). FHL tendinosis is commonly seen in ballet
dancers due to repetitive plantar flexion. If associated
with nodularity, the FHL tendon may cause triggering,
snapping or even a persistent plantar flexed position.

131. Flexor hallucis longus Tear.

133. FHL injuries are associated with extreme plantarflexion and push-off maneuvers, as occur in football players and
ballet dancers. There is chronic muscle strain of the FHL just proximal to the sustentaculum tali. (A) Axial FS PD FSE
with FHL muscle chronic strain (hyperintense signal). (B) Sagittal T1-weighted image showing extreme plantarflexion
in the en pointe position with proximity of the transverse ligament and posterior process.

135. FHL tear proximal to the master knot of Henry. (a) Sagittal inversion-recovery image in a 58-year-old man
shows FHL retraction to the ankle joint (arrow). (b) Short-axis proton-density–weighted MR image at the
master knot of Henry (circled) shows absence of the FHL (black arrow) adjacent to the FDL (white arrow).

137. Tenosynovitis of the flexor hallucis longus.

139. Flexor Hallucis Longus Tenosynovitis.

141. FHL tenosynovitis with a ganglion in a 22-year-old female ballet dancer. Sagittal fat-
suppressed T2-weighted MR image shows FHL tenosynovitis (white arrows) with
secondary ganglion formation distally (black arrow) plantar to the interphalangeal joint.

143. Stenosing tenosynovitis; sagittal PD-fat-saturation-weighted sequence (A and B). Stenosing
tenosynovitis of the FHL tendon (arrows) secondary to os trigonum syndrome (arrowhead in B).

145. Post-traumatic synovitis and stenosing tenosynovitis. A: Axial image acquired after recent ankle injury
demonstrates circumferential fluid (arrow) around the posterior tibial tendon and diffuse soft tissue edema,
corresponding to post-traumatic tenosynovitis. B: Sagittal image exhibits focal fluid distensions and
septations within the flexor hallucis longus tendon sheath, which are indicative of stenosing tenosynovitis.

147. FHL stenosing tenosynovitis (STS). Sagittal T2 FS image showing a large amount of fluid
distending the FHL tendon sheath proximal to the talar fibro-osseous tunnel, suggesting
stenosing tenosynovitis. A flexor digitorum longus accessorious may cause crowding and
contribute to STS. STS may also occur in isolation or in combination with posterior impingement.

149. Gouty involvement of the FHL tendon in a 38-year-old man. Short-axis
contrast material–enhanced fat-suppressed T1-weighted MR image shows
enhancing soft tissue (*) surrounding and invading the FHL tendon (arrows).

151. Giant cell tumour enveloping flexor hallucis longus tendon.

152. Disorders of the Extensor Hallucis Longus Tendon.

153. Chronic partial tear of the extensor hallucis longus in a 25 year old female basketball
player with history of previous injury. An axial fast spin echo T2-weighted image at the
level of the tibiotalar joint reveals a small T2-hyperintense focus (arrow) in the EHL tendon.
Disorders of the Extensor Hallucis Longus Tendon.

155. Chronic rupture of the extensor hallucis longus in a 43 year-old female with anterior pain and inability to extend
the great toe. Sagittal T1-weighted (left) and fat saturated fast spin echo proton density-weighted images (right)
show abrupt termination of the EHL over the anterior talus (arrows), without associated edema or fluid

157. Tendinosis of the extensor hallucis longus. A 17 year-old male basketball player reports anterior right ankle pain. Axial fast
spin echo T2-weighted (left) and sagittal fat saturated fast spin echo T2-weighted (right) images show focal thickening of the
extensor hallucis longus over the anterior tibiotalar joint (arrows), with mild surrounding peritendinous edema.

159. A lateral radiograph of the ankle with
well defined calcification projected along
the dorsal surface of the hind foot.
Sagittal MRI confirming abnormal calcification within
the extensor hallucis and digitorum longus tendons
(arrow) with inflammatory change within the
surrounding soft tissues (arrow).

161. Complete EHL tear in a 41-year-old woman with a midfoot laceration injury. Sagittal
MR image of the forefoot at the level of the first toe shows abrupt EHL tendon
discontinuity (arrows) and a 4-cm tendon gap (*). Lacerations from sharp objects that
fall on the dorsum of the foot are a frequent cause of extensor tendon tears.

163. Tenosynovitis of the
extensor hallucis longus. A
77 year-old female patient
reported difficulty walking
and anterior ankle pain.
Axial fast spin echo T2-
weighted (left), coronal fat
saturated proton density-
weighted (right) and
sagittal fat saturated
proton density-weighted
(bottom) images show
fluid signal and a
mesotendon in the
extensor hallucis longus
tendon sheath.

165. Ganglion cyst displacing the EHL tendon in a 33-year-old woman with a 1-month history of
foot pain. Sagittal (a) and short-axis (b) fat-suppressed T2-weighted MR images of the
midfoot show a multilobulated mass of fluid signal intensity displacing the EHL dorsally
(arrow). A ganglion at that site could also cause entrapment of the medial branch of the DPN.

166. Disorders of the Flexor Digitorum Longus Tendon.

167. FDL tear following hammer toe repair in a 76-year-old woman. (a) Short-axis fat-suppressed proton-
density–weighted MR image shows absence of the FDL tendon slip to the second toe
(arrow). (b) Long-axis fat-suppressed T2-weighted MR image shows the distal tendon stump (arrow).
Disorders of the Flexor Digitorum Longus Tendon.

169. FDL tenosynovitis.

171. Tenosynovitis. (a) Axial T2 FS. Increased T2 weighted signal intensity is visualized about the
FHL (blue arrow) greater than the FDL (red arrow) and PT (yellow arrow) tendons. (b)
Sagittal T2 FS. Increased fluid is again noted within the FHL tendon sheath (blue arrow).
(c) Sagittal T2 FS. A trace amount of increased fluid is noted within the PT tendon sheath.

172. Disorders of the Extensor Digitorum Longus Tendon.

173. Tendinosis of the extensor
digitorum longus. A 40 year-
old female presented with a
palpable anterior ankle mass.
Axial T1-weighted (left) and
fast spin echo T2-weighted
(right) images through a skin
marker placed on the
palpable abnormality reveal
focal thickening of the
extensor digitorum longus
tendon (arrows), with mild
increased signal in the tendon
on the T1-weighted image. A
sagittal fat saturated T2-
weighted image (bottom)
also shows the area of focal
thickening, without increased
intrasubstance signal.
Disorders of the Extensor Digitorum Longus Tendon.

175. Partial tear of the extensor digitorum longus.

177. Tenosynovitis of the distal second and third EDL tendon slips in a 63-year-old woman. Short-axis fat-
saturated proton-density–weighted MR image at the level of the metatarsal shafts shows fluid distending
the tendon sheaths of the second and third EDL divisions (arrows). Unlike in the flexor compartment of the
ankle, fluid in the extensor tendon sheaths, even when minimal, is almost always pathologic.

179. EDL tenosynovitis. Axial and sagittal PD FS images revealing fluid distending the tendon
sheath of the EDL (white arrows). Note the normal appearing ATT (blue) and EHL (orange).

181. Extensor digitorum longus tenosynovitis

183. Tenosynovitis of the extensor
digitorum longus and peroneus
tertius in a 73 year-old male
with anterior ankle pain. Axial
fast spin echo T2-weighted (left)
and sagittal fat saturated
proton density-weighted (right)
images show prominent
distention of the shared tendon
sheath of the EDL and PT
(arrows). Fluid in the tendon
sheath delineates the five
separate tendons of the EDL and
PT on the axial image; the most
lateral tendon is the PT (short
arrow), and the four medial
tendons of the EDL
(arrowheads) insert on the
second through fifth toes.

185. EDL tenosynovitis.

187. Tuberculous tenosynovitis. (a) Pre-contrast - coronal T1-weighted images with gadolinium
enhancement show tenosynovitis in the distal portion of the lower limb - thickening of the
extensor digitorum longus (white arrows) and anterior tibial (arrow heads) tendons.

189. Reactive arthritis and tenosynovitis of multiple tendons in a 38-year-old man. Axial fat-suppressed T2-
weighted MR image shows synovitis and sheath distention of the AT (straight white arrow), EDL (curved
white arrow), and peroneal tendons (black arrow) with debris or synovial hypertrophy. Involvement of
multiple tendons and debris within tendon sheaths usually reflect inflammatory arthritis.

191. Painful swelling in the right ankle diagnosed with tuberculous tenosynovitis. Axial T1-
weighted images at the level of the right tibiotalar joint demonstrate contrast enhancement
of the extensor digitorum longus (black arrows) and tibialis anterior tendons (arrow heads)
and surrounding smooth tissue. The extensor hallucis longus tendon is normal (white star).

193. Tuberculous tenosynovitis. Axial fat-suppressed T2-weighted MR images at the level of the right tibiotalar
joint shows thickening of the extensor digitorum longus (arrows) and tibialis anterior tendons (arrow
heads), peritendinous edema and minimal fluid within the synovial sheath, edema in the surrounding
subcutaneous tissues with loss of fat planes and increased signal intensity within the tendons.

194. Sinus tarsi syndrome.

195. Sinus tarsi ganglion mimicking EDL tenosynovitis in a 43-year-old man. Sagittal (a) and axial (b) fat-
suppressed T2-weighted MR images show a sinus tarsi ganglion (straight white arrows in a) insinuating
between the retinacular roots (black arrow in a) and partially enveloping the EDL tendon (curved white
arrow). A tear of the anterior talofibular ligament (black arrow in b) is seen with fluid distending the
sheaths of the flexor and peroneal tendons (* in b), findings related to a recent inversion injury.
Sinus tarsi syndrome.

197. Sinus Tarsi Syndrome.

199. Subtalar arthritis with sinus tarsi syndrome.

203. Retinacular injury after ankle inversion injury in a 29-year-old woman. Axial
proton-density–weighted MR image of the distal aspect of the ankle shows marked
thickening and heterogeneity of the inferior extensor retinaculum (arrows).

204. Disorder of the lateral ankle ligaments.

206. T1-weighted spin-echo image demonstrates thickening and contour irregularity of the anterior inferior tibiofibular
ligament (arrow). (b) Fat-suppressed T2-weighted fast spin-echo image shows intraligamentous edema, contour
irregularity, and surrounding edema involving the anterior inferior tibiofibular ligament (arrow).

208. Axial STIR MRI image showing rupture of the
anterior inferior tibiofibular ligament (AITFL)

210. Complete anterior talofibular ligament injury.

214. Disorder of the Medial ankle ligaments.

215. Axial T1-weighted (left) and coronal proton density-weighted fat-suppressed (right) images demonstrate loss
of the normal striations of the PTTL with increased signal indicating edema and contusion (asterisks).
Disorder of the Medial ankle ligaments.

217. Coronal proton density fat-suppressed (left), axial T2-weighted FSE (middle), and sagittal T2-weighted fat-
suppressed (right). In this pattern the anterior superficial ligaments fail initially. Proximal (type I) avulsion of
the tibionavicular ligament is demonstrated at the anterior margin of the anterior colliculus (arrows) and ill-
defined, lax and edematous distal ligament fibers (arrowheads) are apparent. The patient also had a tear of
the anterior inferior tibiofibular ligament and a non-displaced spiral fracture of the distal fibular shaft.

219. Coronal fat-suppressed images through the posterior (left) and anterior (right) portion of the anterior colliculus
demonstrate a chronic partial avulsion of the tibial spring ligament (arrowheads). On the more anterior slice the
tibionavicular ligament (arrow) is abnormally thickened and low in signal indicating fibrosis from remote trauma.
The posterior tibial tendon (PT) and superomedial portion of the spring ligament complex (SL) are labeled.

221. Coronal proton density fat-suppressed (left) and axial T2-weighted FSE (right) images demonstrate bare
cortex at the intercollicular sulcus (arrowheads) with fluid signal filling the ligament defect (asterisk). In
addition the superficial ligaments are scarred and appear abnormally thickened and irregular compatible
with a chronic tear. The posterior tibial (PT) and flexor digitorum longus (FDL) tendons are indicated.

223. Coronal proton density-weighted fat-suppressed (middle), and axial T1-weighted images
demonstrate distortion and thickening of the posterior tibiotalar ligament containing
embedded ossicles (arrowheads) compatible with posteromedial impingement.

226. Deltoid ligament sprain. (a, b) Coronal and axial T2 FS. Increased T2
weighted signal intensity is visualized within the posterior deep fibers of
the deltoid ligament (yellow arrows), compatible with grade 2 sprain.

228. Multi-ligamentous injuries. (a) Axial T2 FS. Intermediate T2 weighted signal intensity within and irregularity of
the anterior tibiofibular ligament (blue arrow) is compatible with a partial tear. (b) Axial T2 FS. Complete
disruption of the ATFL is evident (red arrow). The PTFL is intact, but appears mildly thickened with increased T2
weighted signal intensity (yellow arrow), consistent with partial tear. (c) Coronal T2 FS. Intermediate T2 weighted
signal intensity is visualized within the deep posterior deltoid ligament (orange arrow), compatible with a partial
tear. Opposing contusions are seen within the medial malleolus and medial talar dome (green arrows).

229. Osteochondral lesions.

230. Lateral OLT with intact overlying chondral surface. Subchondral trabecular fracture and adjacent marrow edema
are demonstrated on a coronal T1-weighted image (A). Mid-lateral talar dome location is shown with a cross-
sectional area of reactive marrow edema. The edema associated with OLT should not be misinterpreted and
result in overestimation of the area of trabecular bone involved. Coronal T1-weighted image. (B) Coronal FS PD
FSE image. (C) Axial FS PD FSE image. (D) Color illustration with the capsule cut and the tibia and fibula reflected.
Compression-type OLT corresponding with an area of subchondral trabecular compression in a stage I lesion.
Osteochondral lesions.

232. Stage II (IIB) OLT with a shallow and wafer-shaped fragment and incomplete separation from the lateral talar dome. (A) Coronal
T1-weighted image. (B) Coronal FS PD FSE image. (C) Sagittal FS PD FSE image. (D) A nondisplaced partial fracture shown in a
color graphic corresponding to either a communication with the talar dome or an open articular surface lesion with incomplete
separation of the fragment. Subchondral cystic lesions are associated with extension of a fracture to the talar chondral surface.

234. (a) Coronal T1. A subcentimeter osteochondral fracture of the medial talar dome is present (red
ellipse). (b) Coronal T2. A rim of T2 weighted hypointense signal is visualized along the margin of the
osteochondral defect (yellow arrow). No intervening fluid is present to suggest an unstable injury.

236. Nondisplaced fragment in a stage III OLT with intermediate-signal-intensity granulation tissue
at the fragment—talus interface. (A) Sagittal T1-weighted image. (B) Sagittal FS PD FSE image.

238. (A) Stage IV OLT with interruption of the subchondral plate, subchondral cystic change, and medially displaced chondral
fragment on a coronal section color illustration. (B, C) Stage IV OLT with the displaced fragment located in the anterior
tibiotalar joint capsule. The lateral OLT is the donor site. Arthroscopy is performed on all stage III and IV lesions and stage I and
II lesions that fail conservative treatment. (B) Coronal T1-weighted image. (C) Axial FS PD FSE image. (D) Displaced fragment
from a medial talar dome donor site in OLT on a color graphic superior view of the talus with the tibia and fibula resected.

240. Osseous contusions. (a) Sagittal PD FS. Increased T2 weighted signal intensity is identified
within the talus (blue arrow) and cuboid (red arrow). (b) Coronal T2. Again identified is
increased T2 weighted signal intensity within the talus, consistent with contusion.

242. Talocalcaneal coalition. (a) Sagittal PD FS. The middle facet of the subtalar joint is broadened,
with osseous (blue arrow) and fibrocartilagenous (yellow arrows) bridging identified. Associated
mild edema is also noted in the talus and calcaneus (green arrows). Axial T2 FS. Talocalcaneal
coalition of the middle facet is again evident (orange arrow). Increased T2 weighted signal
intensity within the adjacent talus and calcaneus (orange arrows) is compatible with edema.

243. Os trigonum syndrome.
Os Trigonum syndrome.

244. Os Trigonum syndrome.

246. Os trigonum syndrome. Sagittal PD FS. A prominent os trigonum is evident (blue arrow). Significant
surrounding soft tissue edema is present (yellow arrows). Increased signal intensity is also visualized
within the accessory os and posterior talus (orange arrows), consistent with marrow edema.

248. Os trigonum syndrome.

253. Tarsal tunnel syndrome.

254. Tarsal tunnel syndrome.

258. Tarsal tunnel syndrome. (a) Axial
T1. There is marked enlargement
of the tibial nerve (blue ellipse).
(b) Axial T1. Post-surgical changes
of prior flexor retinaculum release
are visualized (red arrow), as
evidenced by thickening and
discontinuity of the retinaculum
and overlying scarring of the
subcutaneous tissues. (c) Axial T2
FS. Enlargement of and
intermediated T2 weighted signal
intensity within the abductor
hallucis muscle (yellow arrow) are
evident. (d) Sagittal PD FS.
Enlargement of and edema within
the flexor digitorum brevis muscle
(purple arrow) are also identified.
This constellation of findings is
consistent with tarsal tunnel
syndrome and compression of the
plantar branch of the tibial nerve.

260. Baxter Neuropathy. (a,b) Sagittal and axial T1. Isolated fatty atrophy of the abductor
digiti minimi muscle, consistent with chronic compression of the inferior calcaneal nerve.

262. RHEUMATOID ARTHRITIS OF ANKLE JOINT. sagittal T1-weighted without an with
contrast administration shows active inflammatory pannus affecting posterior
subtalar joint, marginal bone erosions and subcutaneous rheumatoid nodule are seen.

263. Plantar Fasciitis.

264. Plantar Fasciitis.
Plantar Fasciitis.

266. Plantar Fasciitis.

268. Plantar Fasciitis.

269. Bursa.

270. Bursa.

275. Avascular necrosis.

276. Köhler disease.
Avascular necrosis.

278. Köhler disease

280. Köhler disease.

282. Mueller-Weiss syndrome.

284. Avascular necrosis of navicular bone.

285. Thank You.