Pain with disruption of cartilaginous synchondrosis between os trigonum & lateral tubercle of posterior talar process Anatomical variations: 1. normal tubercle 2.stedia’s process or enlarged tubercle 3.accessory bone or os trigonum 4.fused os trigonum via synchondrosis with talus. Fusion o os trigonum -- 8 to 11 yrs Ossification -- 2nd decade Pain syndrome -- 20 to 35 yrs PROTOCOL: sagittal view T1 , FS PD FSE MRI: T1: Hyointense sclerosis,edema b/w os trigonum & talus T2:Hyperintense marrow edema and edema posterior to talus & superior to os trigonum Differential diagnosis: Fracture lateral tubercle Posterior soft tissue impingement FHL tenosynovitis Dancer’s foot FHL checkrein deformity Accessory navicular: Unattached accessory bone or synchondrosis within medial navicular Types: 1. 4 to 6 mm 2. unossified zone of 1 to 3 mm 3.cornuate or enlarged navicular tuberosity Ossify at 9 to 11 yrs Symptoms after 5 yrs PROTOCOL: direct axial T1 & FS PD FSE or STIR MRI: T1: 1. small (4-6mm) marrow fat containing ossicle within TP tendon (seperated from navicle by 5-7 mm) 2. triangular or heart shaped ossicle with direct connection to medial navicular 3.cornuate extension of medial navicular with no synchondrosis T2: In types 1 & 2 – suppressed marrow fat signal in type 3 - normal marrow fat characteristics Differential diagnosis: Navicular tuberosity fracture TP tendon tear Midfoot arthritis Sesamoid dysfunction: Bipartite, fracture, turf toe , osteochondritis, sesamoiditis Altered signal & morphology of sesamoids Mc – within the double tendons of flexor hallucis brevis , articulating with 1st metatarsal head Bipartite- rounded edges Fracture- discrete hypointense frcture line Turf toe- capsular disruption Dd: stress fracture , synovitis Compartment syndrome: Compartments MRI: T1: intermediate signal in edematous muscle, loss of normal muscle striations T2:hyperintensity of involved muscles D/d: DVT Gastrocnemius-soleus muscle strain Cellulitis Tumour Myositis ossificans Gastro-soleus strain: Diffuse hyperintensity of medial head of gastro & soleus MRI: T1: intermediate signal edema laxity of intermuscular septum b/w the 2 muscles T2: hyperintense edematous muscle fibers GRADES: 1. no myofascial disruption edema,swelling + 2. weakness variable seperation of muscle from tendon orfascia 3. complete myofascial seper

1. Overuse
syndromes of
ankle

2. Os trigonum syndrome
• Pain with disruption of cartilaginous
synchondrosis between os trigonum
& lateral tubercle of posterior talar
process
• Anatomical variations:
1. normal tubercle
2.stedia’s process or enlarged
tubercle
3.accessory bone or os trigonum
4.fused os trigonum via
synchondrosis

3. • Fusion o os trigonum -- 8 to 11 yrs
• Ossification -- 2nd decade
• Pain syndrome -- 20 to 35 yrs
• PROTOCOL:
sagittal view
T1 , FS PD FSE

4. Os trigonum syndrome

5. MRI:
T1: Hyointense
sclerosis,edema b/w
os trigonum & talus
T2:Hyperintense marrow
edema and
edema posterior to talus
& superior to os trigonum

6. Differential diagnosis
• Fracture lateral tubercle
• Posterior soft tissue impingement
• FHL tenosynovitis
• Dancer’s foot
• FHL checkrein deformity

7. Accessory navicular

8. Accessory navicular
• Unattached accessory bone or
synchondrosis within medial
navicular
• Types:
1. 4 to 6 mm
2. unossified zone of 1 to 3
mm
3.cornuate or enlarged
navicular

9. • Ossify at 9 to 11 yrs
• Symptoms after 5 yrs
• PROTOCOL:
direct axial
T1 & FS PD FSE or
STIR

10. • MRI:
T1:
1. small (4-6mm) marrow
fat containing ossicle within TP
tendon (seperated from navicle by 5-
7 mm)
2. triangular or heart
shaped ossicle with direct connection
to medial navicular
3.cornuate extension of
medial navicular with no

11. • T2:
In types 1 & 2 – suppressed
marrow fat signal
in type 3 - normal marrow
fat characteristics

16. Differential diagnosis
• Navicular tuberosity fracture
• TP tendon tear
• Midfoot arthritis

17. Sesamoid dysfunction
• Bipartite, fracture, turf toe ,
osteochondritis, sesamoiditis
• Altered signal & morphology of
sesamoids
• Mc – within the double tendons of
flexor hallucis brevis , articulating
with 1st metatarsal head

18. • Bipartite- rounded edges
• Fracture- discrete hypointense
frcture line
• Turf toe- capsular disruption
• Dd:
stress fracture , synovitis

19. Sesamoid dysfunction

24. Compartment syndrome
• Compartments
• MRI:
T1: intermediate signal in
edematous muscle, loss of normal
muscle striations
T2:hyperintensity of involved
muscles

25. Posterior compartment
synd..

27. Differential diagnosis
• DVT
• Gastrocnemius-soleus muscle strain
• Cellulitis
• Tumour
• Myositis ossificans

29. Gastro-soleus strain
• Diffuse hyperintensity of medial head of
gastro & soleus
• MRI:
T1: intermediate signal edema
laxity of intermuscular septum
b/w
the 2 muscles
T2: hyperintense edematous muscle
fibers

30. • GRADES:
1. no myofascial disruption
edema,swelling +
2. weakness
variable seperation of
muscle
from tendon or fascia
3. complete myofascial
seperation
lack of muscle function

31. • DD:
1.plantaris tendon rupture
2.DVT
3.posterior compartment synd..

32. Gastrocnemius soleus strain

34. Plantaris rupture
• MRI:
T1: intermediate signal mass
b/w medial head of gastrocnemius &
soleus
T2: hyperintense hemorrhage
with hypointense hemosiderin rim
“comet sign”

36. Diff.diagnosis
• Gastro-soleus muscle strain
• Posterolateral corner sprain
• Posterior compartment synd..

37. Plantaris rupture

39. Tarsal tunnel synd..
• Etiology: fracture, ganglion, lipoma,
neurilemmoma, idiopathic.
• Mean age- 47 yrs, female
• Dd: morton’s neuroma, L5 & S1
radiculopathy, tarsal coalition, tibialis
posterior tenosynovitis

40. Tarsal tunnel syndrome

41. Abductor hallucis
denervation

43. Plantar fascitis
• Site
• MRI:
T1: hypointense thickening of
fascia
T2: intermediate to
hyperintense
thickening

44. Diff.diagnosis
• Plantar fibromatosis
• Tarsal tunnel synd.
• Calcaneal stress frcture

45. Plantar fascitis

49. Plantar fibromatosis
• Nodular thickening
• Definitive plantar margin with
infiltrative dorsal margin
• >65 yrs, male
• dd: plantar fascitis, lipoma, ganglion
cyst

50. Plantar fibromatosis

53. Morton’s neuroma
• 3rd common digital branch of medial
plantar nerve
• 40 – 60 yrs, female
• MRI: T1: hypo to intermediate signal tear
drop shaped mass
T2: intermediate to yperintense
mass
T1 C+ : diffuse enhancement

54. Morton’s neuroma

55. Diff.diagnosis
• Metatarsal stress fracture
• Osteochondrosis
• Tarsal tunnel synd.

58. Diabetic foot
• Diabetic foot ulcers, infection, neuropathic
arthropathy
• MRI:
T1: neuropathic arthropathy –
hypointense replacement of fat marrow
T2: neuropathy & osteomyelitis -
hyperintense

59. Diabetic foot

60. Diff.diagnosis
• Osteo arthritis
• Osteonecrosis
• infection

66. Thank you
DR.G.Surekha Babu,
Resident, BIR