Clinical Outcomes for Pilon Variant Posterior Malleolar Fractures: A Multicenter Retrospective Analysis

Currently, there is no consensus on surgical approach for posterior malleolar fracture fragments with significant posteromedial involvement. The Bartonicek type III/Haraguchi type II posterior malleolar morphologies typically involve large posteromedial fragments, behaving like a pilon injury and have been reported as pilon variant fractures. We performed a retrospective chart review at 2 large healthcare institutions, evaluating patients that underwent surgical management of pilon variant posterior malleolar fractures and determining clinical outcomes including: time to union, union rates, soft tissue complications, infection and time to weight bearing. A total of 68 patients were included (51 females, 17 males). A total of 51 direct (19 posterolateral, 31 posteromedial), 6 indirect, and 11 no-fixation approaches were identified. Significantly different time-to-union was found between direct fixation (mean = 85.1 days), indirect fixation (mean = 74 days) and no-fixation (mean = 174.3 days) (p < .001). A posteromedial approach (mean = 63.0 days, SD = 16.6) was associated with significantly shorter time to union when compared to a posterolateral approach (mean = 124.8 days, SD = 59.4; p < .001). Fixation (direct or indirect) was associated with significantly increased likelihood of union of the overall ankle fracture pattern (52/57 = 91%) when compared to no fixation of the posterior malleolar component (9/14 = 64%), p = .01. Patients who underwent direct fixation had significantly lower incidence of neurovascular damage (6%) when compared to patients who underwent indirect fixation (33%) or no-fixation (29%) (p = .02). There was no significant difference between the groups in terms of tendon damage (p = .54), infection rates (p = .45) and time to weight bearing (p = .66). The authors suggest that surgical management and specifically direct approaches have better outcomes in the short-term follow up.