Posterior Column Involvement in AO/OTA 41B3 Lateral Split-Depression Tibial Plateau Fractures Leads to Worse Outcomes

The purpose of this study was to compare outcomes in patients who sustained isolated lateral column tibial plateau fractures and combined lateral and posterolateral column tibial plateau fractures (AO/OTA 41B3 lateral split-depression fractures). Fractures were classified according to the three-column classification system of tibial plateau fractures. The primary outcome was the difference in Short Musculoskeletal Function Assessment (SMFA) function index at 12 months postoperatively between patients with lateral column plateau fractures and patients with combined lateral and posterolateral column plateau fractures. Seventy-eight patients were included (mean age: 48.8 ± 14.1 years). Thirty-two patients (41.0%) were in the isolated lateral column group (L), and 46 patients (59.0%) were in the lateral column plus posterolateral column group (L + PL). At 1 year following injury and fixation, the L + PL group demonstrated significantly worse SMFA function index than the L group (19.1 ± 17.7 vs. 9.1 ± 12.5, p = 0.005). Similarly, the L + PL group was significantly more bothered by the sequelae of their injury compared to the L group at 1 year based on the SMFA bothersome index (20.7 ± 23.7 vs. 8.6 ± 12.3, p = 0.005). Patients with combined lateral and posterolateral column tibial plateau fractures demonstrate worse outcomes compared to isolated lateral column fractures 1 year after fixation. The study provides level III evidence.