Mid-Term Osteoarthritis Prevalence After Partial Meniscectomy in Knees With High Posterior Tibial Slope

Abstract

Background: While meniscal repair and partial meniscectomy are common treatments for meniscal tears, their comparative influence on mid-term osteoarthritis (OA) progression, particularly in relation to patient-specific anatomic factors, such as posterior tibial slope (PTS), and lesion-specific characteristics, such as tear morphology, remains incompletely understood. Purpose: To compare mid-term OA development and clinical outcomes after meniscal repair versus partial meniscectomy, evaluating the influence of PTS and tear morphology. Study Design: Cohort study; Level of evidence, 3. Methods: This retrospective comparative cohort included 378 knees treated with partial meniscectomy (n = 202) or meniscal repair (n = 176), with a minimum 5-year follow-up. The primary outcome was incident radiographic OA, defined as progression from a baseline Kellgren-Lawrence (K-L) grade of 0 or 1 to a K-L grade of ≥2 at final follow-up. Secondary outcomes included revision rates, complications, and patient-reported outcome measures (International Knee Documentation Committee [IKDC], Lysholm). High PTS was defined as >10°; and PTS, tear morphology, and the procedure-by-PTS interaction were evaluated using multivariable models. Results: At a mean follow-up of 8.1 ± 2.4 years, the incident radiographic OA was more frequent after partial meniscectomy than meniscal repair (47.5% vs 24.4%; P < .001). High PTS was associated with an increased incidence of radiographic OA (62.7% vs 22.5%; P < .001), and a significant procedure-by-PTS interaction was observed (P = .01), suggesting that this association differed between partial meniscectomy and meniscal repair. Compared with partial meniscectomy, meniscal repair was associated with higher final IKDC and Lysholm scores (both P < 0.001), but also with a higher revision rate (15.9% vs 6.4%; P = .003) and a shorter mean time to revision (2.6 vs 4.1 years; P = .02). Early complication rates were comparable (P = .68). Conclusion: Partial meniscectomy was associated with greater mid-term radiographic OA progression than meniscal repair. PTS and tear phenotype should be considered in preoperative decision-making, although these findings should be interpreted in light of the retrospective study design and potential residual confounding.