AVN of the talus is least likely to occur in patients who demonstrate radiographic evidence of Hawkins sign at 6 to 8 weeks postinjury. Hawkins type II talar neck fractures have a 20% to 50% risk of AVN. However, the increased subchondral radiolucency in the dome of the talus represents an increase in bone reabsorption, which indicates active hyperemia in the bone and the presence of vascular perfusion, making AVN unlikely. After surgical open reduction with internal fixation, nonunion and delayed union can occur, but the rates are low (4% and 10%, respectively).3 Persistent slight displacement of the talus after open reduction with internal fixation is difficult to recognize and occasionally results in varus malunion with poor joint mechanics. One common postsurgical complication is ankle stiffness, which can be minimized with range of motion exercises. Another common result is subtalar, ankle, and talonavicular arthritis due to initial traumatic osteoarticular damage to the joints of the proximal foot.3
- AVN of the talus.
3. Vallier HA, Nork SE, Barei DP, et al. Talar neck fractures: results and outcomes. J Bone Joint Surg Am 2004;86-A:1616-24.
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