Association between MRI-based anterior tibial translation and patellofemoral cartilage damage one year after anterior cruciate ligament reconstruction

Abstract

The patellofemoral joint is affected by biomechanical alterations to the knee joint following Anterior cruciate ligament (ACL) reconstruction. This study aimed to investigate the relationship between MRI-based Anterior Tibial Translation (ATT) measurements and patellofemoral joint chondral damage following ACL reconstruction. This retrospective study included 40 patients who underwent ACL reconstruction using an autograft between 2020 and 2024 were included in this study. The mean postoperative MRI acquisition time was 11.97 ± 3.23 months. Patellofemoral cartilage lesions were primarily evaluated using the MRI Osteoarthritis Knee Score (MOAKS) scoring system. Patients were classified into rotation groups according to the difference between their ATT-L and ATT-M values. The ATT-L-ATT-M difference was calculated and rotational groups defined: ± 2 mm, neutral; > 2 mm, internal; and < -2 mm, external rotation. The mean age of the patients was 28.93 ± 9.62 years, with 80% of the patients were male. Patellar cartilage damage was detected in 11 (27.5%) patients. The mean ATT-L was 6.075 ± 5.47 mm, whereas the mean ATT-M was 1.84 ± 4.39 mm. No significant association was observed between patellofemoral cartilage damage and either ATT-L or ATT-M (p = 0.575 and p = 0.228, respectively). The cartilage damage rate was 17.9% in the internal rotation group, compared to 50.0% in the neutral and external rotation groups. Cartilage damage was observed significantly less frequently in the internal rotation group than in the neutral and external rotation groups (p = 0.037). Early patellofemoral cartilage damage may be associated with patellofemoral morphology and tibial rotational profile rather than with isolated medial or lateral ATT measurements one year after ACL reconstruction.