[Is the Hawkins sign able to predict necrosis in fractures of the neck of the astragalus?].

OBJECTIVE To assess if the Hawkins sign can predict whether or not astragalus fractures of the neck will develop avascular necrosis. It is also assessed whether the occurrence of this complication is related to the displacement of the fracture, soft tissue injury, or delay in the reduction or surgery. The results were compared with those found in the literature. MATERIAL AND METHODS A retrospective study was conducted on 23 talar neck fractures recorded over a a period of thirteen years. The following variables were analysed: displacement of the fracture, soft tissue injury, delay and type of treatment, complications, observation of the Hawkins sign, and functional outcome. RESULTS There were 7 type I Hawkins fractures, 11 type II, and 4 type III and 1 type IV. Four cases developed avascular necrosis (2 Hawkins type II and 2 type III). Hawkins sign was observed in 12 cases, of which none developed necrosis. Four cases with negative Hawkins sign developed necrosis. No statistically significant differences were found when comparing the development of avascular necrosis with the displacement of the fracture, soft tissue injury, or delay in treatment. Differences were found when comparing the development of avascular necrosis with the Hawkins sign (P=.03). CONCLUSION A positive Hawkins sign rules out that the fractured talus has developed avascular necrosis, but its absence does not confirm it.