Answer for BIR CoW 09 Nov 2025
AVASCULAR NECROSIS OF TALUS
Findings
Non united comminuted displaced fracture of talus with sclerosis of fracture fragments. Subchondral lucency noted in head and dome of talus with adjacent sclerotic changes. Joint space widening noted involving the subtalar joint. Multiple old linear pintracts noted along the medial aspect of tibia and calcaneum.-Postoperative changes Small bony protruberance noted arising from posterosuperior aspect of calcaneum and osteophyte noted arising from distal tibia IMPRESSION: Non united comminuted displaced fracture of talus with possibility of avascular necrosis.
Discussion
The talus is predisposed to avascular necrosis (AVN), or bone death due to ischemia, owing to its unique structure, characteristic extraosseous arterial sources, and variable intraosseous blood supply. Both traumatic and atraumatic causes have been implicated First signs can be observed 6–8 weeks post fracture. The Hawkins sign is a subchondral radiolucent band in the dome of the talus. This results from an increase in bone reabsorption relative to bone formation, and it manifests with active hyperemia of the bone. Ficat and Arlet scale for Talar Avascular Necrosis. Stage X-ray Findings I (Preradiographic) Normal II (Precollapse) Bone remodelling, subchondral cysts III (Post collapse) Crescent sign IV (Arthritis) Talar bone deformation, joint space narrowing
Reference: Pearce D, Mongiardi C, Fornasier V, Daniels T. Avascular Necrosis of the Talus: A Pictorial Essay. Radiographics. 2005;25(2):399-410.
Findings
Non united comminuted displaced fracture of talus with sclerosis of fracture fragments. Subchondral lucency noted in head and dome of talus with adjacent sclerotic changes. Joint space widening noted involving the subtalar joint. Multiple old linear pintracts noted along the medial aspect of tibia and calcaneum.-Postoperative changes Small bony protruberance noted arising from posterosuperior aspect of calcaneum and osteophyte noted arising from distal tibia IMPRESSION: Non united comminuted displaced fracture of talus with possibility of avascular necrosis.
Discussion
The talus is predisposed to avascular necrosis (AVN), or bone death due to ischemia, owing to its unique structure, characteristic extraosseous arterial sources, and variable intraosseous blood supply. Both traumatic and atraumatic causes have been implicated First signs can be observed 6–8 weeks post fracture. The Hawkins sign is a subchondral radiolucent band in the dome of the talus. This results from an increase in bone reabsorption relative to bone formation, and it manifests with active hyperemia of the bone. Ficat and Arlet scale for Talar Avascular Necrosis. Stage X-ray Findings I (Preradiographic) Normal II (Precollapse) Bone remodelling, subchondral cysts III (Post collapse) Crescent sign IV (Arthritis) Talar bone deformation, joint space narrowing
Reference: Pearce D, Mongiardi C, Fornasier V, Daniels T. Avascular Necrosis of the Talus: A Pictorial Essay. Radiographics. 2005;25(2):399-410.
Note:
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!