Revision rates are similar after surgical treatment of acute chondral and osteochondral injuries following patellar dislocation: A multicentre cohort study

PURPOSE: Optimal treatment strategies for (osteo-)chondral injuries following patellar dislocation remain unclear. This retrospective multicentre study aimed to compare outcomes between chondral and osteochondral lesions and to explore factors associated with revision surgery. METHODS: Patients who underwent surgical treatment for (osteo-)chondral injuries secondary to patellar dislocation over a 10-year period were included. The primary endpoint was revision surgery; secondary endpoints included patient-reported outcome measures (PROMs) (Banff Patellofemoral Instability Instrument 2.0, EuroQol 5-Dimension [EQ-5D], International Knee Documentation Committee [IKDC-2000] and Marx Activity Rating Scale). Outcomes were compared between chondral and osteochondral lesions using multivariable regression models to adjust for clinically relevant confounders. RESULTS: A total of 208 patients with chondral and/or osteochondral defects were included (chondral: 27.4%; osteochondral: 71.2%; combined chondral and osteochondral: 1.4%). Only patients with purely chondral or osteochondral lesions were further analysed (n = 205). Treatment strategies differed between groups, with fragment refixation more commonly performed in osteochondral lesions (62.8% vs. 19.3%, p < 0.001). Overall, 11.2% of patients underwent revision surgery, with no significant difference between lesion types. Concomitant stabilising procedures were associated with lower odds of revision surgery (adj. p = 0.005). Patients with chondral lesions had higher scores in the Marx Activity Rating Scale (adj. p = 0.017). CONCLUSIONS: No significant difference in revision rates was observed between chondral and osteochondral lesions following patellar dislocation. Concomitant stabilising procedures were associated with lower odds of revision surgery. Given the retrospective design and limited number of events, these findings should be considered exploratory and require confirmation in prospective studies. LEVEL OF EVIDENCE: Level III.