The cumulative incidence and risk factors associated with 5-year conversion to knee arthroplasty following primary meniscus repair or primary meniscectomy.

ABSTRACT

Background: This study aimed to observe the 5-year knee arthroplasty conversion incidence rate and associated risk factors in patients who underwent meniscus procedures. Methods: Using a national database, we analyzed patients who had undergone primary meniscus repair or meniscectomy without prior knee surgeries. The cumulative knee arthroplasty conversion incidence was determined via Kaplan Meier analysis. Risk factors for conversion within 5 years were assessed using a Cox proportional hazard ratio model, with results as hazard ratios (HR). Results: 8125 patients had meniscus repair, while 240,209 had meniscectomy. 5-year conversion rates repair 1.7%, meniscectomy 8.4%. Arthroplasty likelihood decreased as age decreased for repair (70+ [HR 162.20]; 60-69 [HR 81.64]; 50-59 [HR 49.85]; 40-49 [HR 17.79]; p < 0.001 all). Additional risk factors included male sex (HR 0.35; p < 0.001) and higher Charlson Comorbidity Index (CCI) (CCI1 [HR 1.28; p = 0.012]). For meniscectomy, arthroplasty likelihood also decreased with age (70+ [HR 99.41]; 60-69 [HR 84.57]; 50-59 [HR 66.60]; 40-49 [HR 36.15]; 30-39 [HR 10.18]; p < 0.001 all). Additional risk factors included male sex (HR 0.68; p < 0.001), obesity (HR 1.18; p < 0.001), smoking (HR 0.1.12; p = 0.010), and higher CCI (CCI1 [HR 1.25]; CCI2 [HR 1.39]; CCI3+ [HR 1.46]; p < 0.001 all). Conclusion: This study revealed the national 5-year conversion incidence following primary meniscus repair (1.7%) and meniscectomy (8.4%). It also enhanced understanding of age, sex, obesity, smoking, comorbidities (CCI), and knee arthroplasty likelihood after meniscus procedures.