The Increased Tibiofemoral Rotation: A Potential Contributing Factor for Patellar Maltracking in Patients with Recurrent Patellar Dislocation

Abstract

Abstract Objective The purpose of this study was to analyze the relationship between tibiofemoral rotation and patellar maltracking in patients with recurrent patellar dislocation. Methods A total of 143 consecutive knees (118 patients) with clinically diagnosed recurrent patellar dislocation from January 2018 to December 2019 were retrospectively analyzed. Patellar tilt angle and bisect offset index were recorded on axial CT to assesses the severity of patellar maltracking. Tibiofemoral rotation angle is measured by comparing the angle between the posterior femoral and tibial condylar lines on three‐dimensional CT. The Pearson correlation was calculated to investigate the association between tibiofemoral rotation angle and patellar maltracking. Patients were divided into the rotation group (≥15°) and control group (20 mm, the increased TT‐TG distance was mainly caused by tibiofemoral rotation angle in group C (TT‐TG > 20 mm, TT‐PCL 20 mm, TT‐PCL > 24 mm). Bisect offset index and patellar tilt angle were significantly higher in the group C than group D. Conclusion The increased tibiofemoral rotation angle is associated with patellar maltracking in patients with recurrent patellar dislocation. Patients with increased tibiofemoral rotation angle usually have more severe patellar maltracking.

Keywords

• patellar dislocation
• patellar maltracking
• tibial tubercle‐trochlear groove
• tibiofemoral rotation