Summary

The study shows overall excellent mid-term postoperative outcomes following MPFL reconstruction. It demonstrates a significant influence of BMI on mid-term postoperative outcomes, while age and gender did not have a significant impact.

Abstract

In cases of patellar dislocation, the medial patellofemoral ligament (MPFL) is always injured. The influence of various risk factors, particularly bony anatomy, on postoperative outcomes is well-documented and addressed in the treatment of patellofemoral instability (PFI). However, the impact of gender, age, and BMI on isolated MPFL reconstruction remains unclear. This study aims to investigate outcomes following isolated MPFL reconstruction and assess the effects of gender, age, and BMI on these outcomes.
This monocentric study included patients over 12 years of age who underwent isolated MPFL reconstruction for PFI between January 2017 and January 2022. Exclusion criteria included pathological risk factors such as increased TTTG distance, high-grade trochlear dysplasia, leg axis deviation (> 5°), distortion errors, and patella alta.
Preoperative patient-reported outcome measures (PROMs) (KOOS, IKDC, Tegner Activity Score (TAS), and VAS) were collected and compared with postoperative PROMs (KOOS, IKDC, TAS, VAS, BANFF-Score) during follow-up. A logistic regression analysis was conducted to identify relevant factors influencing postoperative outcomes.
A total of 105 patients (67 women, 38 men) with an average follow-up of 49.1 months (range: 22.3-83.2 months) were included. The mean age at surgery was 23.44 years (range: 12-46 years), and the average BMI was 25.5 ± 4.8. 87.6% (n=92) of patients reported being subjectively satisfied with the surgical outcome. There was a significant improvement in KOOS, IKDC, and TAS scores postoperatively (p<0.001). Gender did not significantly affect postoperative outcomes (KOOS p>0.31, Kujala p>0.33, BANFF p>0.55, IKDC p>0.73, TAS p>0.1, VAS p>0.75). Age at the time of surgery did not have a significant impact on postoperative outcomes (KOOS p>0.37, Kujala p>0.93, BANFF p>0.57, IKDC p>0.41, TAS p>0.06, VAS p>0.87). Higher BMI showed a significant negative correlation with postoperative outcomes (KOOS p<0.004, IKDC p<0.03, Kujala p<0.005, BANFF-Score p<0.16, TAS p<0.06, VAS p<0.70).