Fracture: Talus

Radiographic findings may include:

  • a linear or curvilinear decreased density dividing a bone into two or more segments
  • ill-defined increased density

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Here are presentations of talar fracture (with *interpretations):

  • Case 1
  • *Case 1
  • Case 2
  • *Case 2
  • Case 3
  • *Case 3
  • Case 4
  • *Case 4
  • Case 5a
  • *Case 5a
  • *Case 5b
  • Case 6
  • *Case 6
  • Case 7a
  • *Case 7a
  • *Case 7b
Fracture talar head
a Fracture avulsion talar head marked
b os supratalare

Lateral views.
a) An ill-defined flake of bone is present along the superior aspect of the talar head.
b) A well-defined ossicle is identified superor to the talar head.
Diagnoses: a) avulsion fracture. b) os supratalare versus nonunion avulsion fracture.

fralcture lateral process
fracture lateral talar process marked

Anteroposterior view.
Two flakes of bone (arrowhead) are identified lateral to the lateral talar process (ltp), which has an ill-defined margin.
Diagnosis: comminuted fracture of lateral talar process (Sneppen group 4).

beak fracture
beak fracture marked

Lateral view.
A large ossicle (F) is separate from an exostosis along the superior surface of the talar head & neck. Other findings include inferior and retrocalcaneal spurs.
Diagnosis: talar beak fracture. Enthesopathy.

osteochondritis dissecans
osteochondritis dissecans marked

Medial oblique ankle view.
An ossicle (o) is seen within a defect along the superomedial aspect of the talar dome.
Diagnosis: osteochondritis dissecans (Sneppen group 1).

a sheperd's fracture b sheperd's fracture lateral
a sheperd's fracture b sheperd's fracture lateral

a) Medial oblique (or, over-rotated mortise) and b) lateral ankle views.
a) An ill-defined ossicle (arrowhead) is seen lateral to the talar posterolateral process (arrow), which is also ill-defined.
b) The ossicle (o) seen posterior to the talus is separated from the posterior process by an ill-defined, linear decreased density (arrowhead). Other findings include an obliquely oriented decreased density (arrows) that runs from superoposterior to inferoanterior through the distal fibular metadiaphysis. A similar finding can be seen in the oblique view, a.
Diagnoses: avulsion fracture of the talar posterolateral process (aka Sheperd's fracture; Sneppen group 3). Oblique fracture of distal fibula.

os trigonum

Lateral view.
A well-defined ossicle articulates with the posterior talar process.
Diagnosis: os trigonum.

talar neck fracture
talar neck fracture marked

Lateral view.
The talar head/neck are separated from the talar body and displaced superiorly. The superior-inferior length of the body is decreased from normal, an ill-defined decreasd density (i) runs perpendicular to the neck, and there is narrowing of both the middle and posterior talocalcaneal joint spaces (arrows).
Diagnosis: talar neck fracture with impaction of the body at the talocalcaneal joints (Hawkins type 2, Sneppen group 5).

talar neck fracture healing
talar neck fracture marked

Lateral view.
An incomplete, curvilinear decreased density runs through the talar neck (arrowhead). Additionally, there is diffuse sclerosis thoughout the talar body and neck.
Diagnosis: healing talar fracture (Hawkins type 1, Sneppen group 2 type 1A).

hawkin's sign 2

Mortise ankle view.
A somewhat well-defined, curvilinear decreased density parallels the talar dome articular surfaces (arrows). A transversely-oriented decreased density runs across the tibial distal metaphysis.
Diagnosis: Acute osteopenia. Hawkin's sign (arrows), indicates an intact vascular supply to the talar body.

Should a radiographic study be ordered to assess the possibility of talar fracture?

Definitely yes.

What are the best views to order?

At a minimum order DP and lateral views. AP, mortise, and/or medial oblique ankle views may be valuable for medial or lateral fractures, including the posterolateral process.

CT may be necessary for pathology that is inconclusive on plain films. MRI may be indicated if additional soft tissue pathology is suspected.

Other information

Bone scintigraphy may be valuable for assessing vascular status.

References:

  1. Christman RA: Foot and Ankle Radiology, 2nd edition, Lippincott Williams & Wilkins, 2015.