Prognostic Role of Lesion Morphology in Patellar Osteochondral Fixation: Influence of Localization and Size on Functional and Pain Outcomes

Background/Objectives: Osteochondral lesions are common after acute patellar dislocation, particularly in young, active individuals. Although fixation of osteochondral fragments is a preferred treatment to restore joint congruence and prevent cartilage degeneration, the prognostic effect of lesion localization and size on postoperative outcomes remains unclear. Methods: This retrospective clinical study included 75 patients (mean age 23.8 ± 6.1 years) who underwent osteochondral fixation after patellar dislocation between 2018 and 2024. Lesions were classified by location—medial patellar facet, lateral facet, trochlear groove/lateral femoral condyle, or multiple regions—and measured on preoperative MRI for size and depth. Functional outcomes were assessed using Kujala, Lysholm, Tegner, and VAS pain scores preoperatively and 12 months postoperatively. Associations between lesion characteristics and postoperative results were analyzed using t-tests, ANOVA, and Pearson correlation. Results: Lesions were most frequently located on the medial patellar facet (42.7%), followed by the trochlear groove/lateral femoral condyle (34.7%). Larger and deeper lesions were more common in trochlear or multiple-site involvement (p = 0.002 and p = 0.031, respectively). At final follow-up, all functional scores improved significantly (Kujala: 62.4 ± 11.3 to 86.7 ± 9.1; Lysholm: 64.1 ± 12.0 to 88.2 ± 8.3; VAS: 6.2 ± 1.3 to 2.1 ± 1.1; all p < 0.001). Patients with smaller lesions (<100 mm²) and medial facet involvement achieved higher Kujala scores (p = 0.020) and lower postoperative pain (p = 0.001). The overall return-to-sport rate was 78.7%, and postoperative complications occurred in 10.7% of cases, mainly recurrent dislocation or implant irritation. Conclusions: Lesion localization and size significantly affect postoperative outcomes after osteochondral fixation for patellar dislocation. Medial facet and smaller lesions are associated with better pain relief and functional recovery, whereas large or trochlear lesions carry a less favorable prognosis. Morphological assessment of lesion characteristics should therefore guide surgical planning, fixation strategy, and postoperative rehabilitation to optimize clinical outcomes.