Ankle Fractures with Posterior Malleolar Fragment: Management and Results

Trimalleolar ankle fractures can be difficult to manage and convey a high risk of long-term morbidity. The question of whether internal fixation of the posterior malleolar fragment is warranted remains open. We conducted a retrospective cohort study involving 45 patients who underwent surgical repair of a trimalleolar fracture. Our goal was to study the effect of the size of the posterior fragment on outcomes. We defined small posterior malleolar fragments as being ≤ 25% of the distal tibial articular surface as viewed on the lateral radiograph. Outcome measures included the radiographic appearance of the reduction, as well as Olerud and Molander (O&M) scores and AOFAS scores. Overall better outcomes were obtained in patients whose fractures involved ≤ 25% of the articular surface, and the difference in outcomes was statistically significant in regard to the AOFAS scores (P = .05), although not statistically significant in regard to Olerud and Molander scores and the radiographic appearance of the reduction (P = .14 and P = .45, respectively). Anatomic reduction was achieved in 73.3% of patients, but they did not have better clinical results than nonanatomic reduction patients: AOFAS (P = .14), O&M (P = .38), radiographic appearance (P = .74).