The purpose of this study is to evaluate the incidence of ankle injury in ipsilateral tibial shaft fractures and to assess the risk factors for ankle injury associated with tibial shaft fractures.

Sixty patients with tibial shaft fractures were enrolled in this retrospective study. The incidence and characteristics of ankle injury were evaluated, and fracture classification, fracture site, and fracture pattern of the tibial shaft fractures were analyzed for assessment of the risk factors for ankle injury combined with tibial shaft fractures.

Ankle injury occurred in 20 cases (33%). There were four cases of lateral malleolar fracture, four cases of posterior malleolar fracture, two cases of distal tibiofibular ligament avulsion fracture, and 10 cases of complex injury. Fourteen cases (70%) of 20 cases of ankle injury were diagnosed from x-ray films, and the other six cases were recognized in ankle computed tomography (CT). Ankle injury occurred in 45.1% of distal tibial shaft fractures and found in 41.4% of A type, but there was no statistical significance. Ankle injury was observed in 54% of cases of spiral pattern of tibial shaft fracture and the incidence was statistically higher than 19% of cases of non-spiral pattern tibial shaft fracture.

Ankle injury was observed in 33% of tibial shaft fractures; however, only 70% could be diagnosed by x-ray. Ankle injury occurred frequently in cases of spiral pattern of tibial shaft fracture, and evaluation of ankle injury with CT is recommended in these cases.