RESUMO
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.
RESUMO
Posterior malleolar fractures are often part of complex ankle fracture patterns. Radiographs and computed tomography are often obtained in the preoperative setting. In this study, we compared measurements from lateral ankle radiographs with measurements on axial computed tomography. We hypothesize that there is an association between measurements taken on lateral XR and certain fracture morphology such as medial extension and that measurements taken on lateral XR can be used to predict likelihood of medial extension type fractures. A multi-center retrospective analysis was performed involving patients with trimalleolar ankle fractures treated at two large urban healthcare systems ranging from January 1, 2010 to November 1, 2019. A total of 279 patients met criteria including 186 females and 93 males aged 18 to 90 with an average age 55. Four reviewers measured continuous variables on lateral radiograph and axial computed tomography: posterior malleolus fracture height, articular surface length, medial-lateral width, and anterior-posterior depth and then agreement was assessed via intraclass correlation coefficient. Pearson correlations were calculated for all pairwise combinations of measurements. Two fracture classification systems were then evaluated for association with the continuous variables. Lateral height was divided into quartiles and analyzed for the degree of association. Positive correlation was found between lateral height and axial depth/axial width. Taller lateral height values were statistically associated with medial extension type fractures. Lateral height 24.5mm-29.5mm is 3.1x higher, and lateral height >29.5mm is 8.6x more likely to have medial extension when compared to shorter lateral heights(<20.5mm). Based on these findings we suggest increased usage of pre-operative CT and evaluation for the use of posteromedial approaches in the setting of taller lateral height fracture patterns(>24.5mm) as seen on lateral XR.
