Incidence, Risk Factors, and Location of Articular Malreductions of the Tibial Plateau.

OBJECTIVES To define the incidence, risk factors, and anatomic location of articular malreductions in operatively treated lateral tibial plateau fractures. DESIGN Prospective Cohort Study. SETTING Academic Level 1 Trauma Centre. PATIENTS/PARTICIPANTS Study subjects were patients entered into a prospective cohort study of tibial plateau fractures. INTERVENTIONS Surgical fixation of tibial plateau fractures and postoperative computed tomographies (CTs). MAIN OUTCOME MEASURES The primary outcome was incidence of articular malreduction. Secondary outcomes included risk factors for malreduction and a descriptive analysis of malreduction location. RESULTS Sixty-five postoperative CTs were reviewed. Twenty-one reductions (32.3%) had a step or gap more than 2 mm. The frequency of malreductions in patients undergoing submeniscal arthrotomy or fluoroscopic-assisted reduction alone was 16.6% and 41.4%, respectively (P = 0.0021). Age, body mass index, OTA/AO fracture type, operative time, use of bone graft or bone graft substitute, and use of locking plates were not predictive of malreduction. Malreductions were heavily weighted to the posterior quadrants of the lateral tibial plateau. CONCLUSIONS When examined using cross-sectional imaging the rate of articular malreductions was high at 32.3%. Fluoroscopic reduction alone was a predictor for articular malreduction. Most malreductions were located in the posterior quadrants of the lateral plateau. LEVEL OF EVIDENCE Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.