Effects of surgical approaches and morphological characteristics on the follow up outcomes of patients with posterolateral tibial plateau fractures

This study aimed to study the effects of surgical approaches and identify the morphological characteristics associated with the 1-year follow-up outcome of patients with posterolateral tibial plateau fractures after successful surgery. We followed 200 postoperative patients for 1 year. The modified Hospital for Special Knee Surgery score (HSS score) was used to evaluate the functional recovery of the knee. We supposed 4 morphological characteristics in CT images acting as possible risk factors, including the anteroposterior diameters of posterolateral broken bone fragments (fragment-diameter), the damage to the posterolateral cortex of the tibial head (cortex-damage), the combinational fracture of the proximal fibula (fibula-fracture) or fracture of the medial tibial condyle (medial-condyle-fracture). Multivariate regression models were used to analyze the effect of these factors on the HSS score after adjusting the 2 surgical approaches and other confounders. The average HSS score was 85.1 ± 5.8 for all the patients. We treated 155 patients with the anterolateral approach and 45 patients with the posterolateral approach. The surgical approach, fragment-diameter, fibula-fracture, and medial-condyle-fracture were correlated with the HSS scores (P < .05). After adjusting for the above factors, the Schatzker type, age and gender, compared with anterolateral approach, the posterolateral approach could improve the HSS scores by an average of 3.7 points. The fragment-diameter <20 mm and posterolateral approach interacted on the HSS scores. Comparing posterolateral and anterolateral approaches, we found that the HSS scores of patients with fragment-diameter <20 mm increased by 6.1 points (95% CI: 4.1–8.2) in the posterolateral approach, while those with fragment-diameter ≥20 mm did not significantly improve the HSS scores. The surgical approach, fragment-diameter, fibula-fracture, and medial-condyle-fracture were independent risk factors associated with the follow-up outcome of patients with posterolateral tibial plateau fractures after successful surgery. The posterolateral approach could significantly improve the HSS score in the studied hospital.