High Rate of Recurrent Meniscus Tear and Lateral Compartment Osteoarthritis in Patients Treated for Symptomatic Lateral Discoid Meniscus: A Long-Term Population-Based Study

Abstract

Objectives: Little is known about the natural history and long-term outcome of a surgically treated symptomatic lateral discoid meniscus. The goals of this study were to describe the rate and factors associated with recurrent lateral meniscus tears and progression to symptomatic lateral compartment osteoarthritis (OA) in patients surgically treated for a symptomatic lateral discoid meniscus. Patients with surgically treated lateral discoid meniscus have a high incidence of meniscus re-tear and progression to lateral compartment OA. Methods: A large, geographic database was reviewed to identify and confirm patients presenting with symptomatic lateral discoid meniscus between 1998 and 2015. Charts were reviewed to document treatment and outcomes at a minimum clinical follow-up of two years. Results: 70 discoid meniscus patients (30 F, 40 M) with a mean age of 27 years (Range: 2.0-66.0) were followed for an average of 5.8 years (Range 2.0-23.7). Sixty patients underwent surgical management: 49 (82%) patients underwent partial lateral meniscectomy and 11 (18%) underwent meniscus repair (including saucerization). Tear-free survival following surgery was 93% at 2 years, 69% at 5 years, and 40% at 8 years. Overall progression to symptomatic lateral compartment OA in the surgical group was 10% at 2 years, 23% at 5 years, and 48% at 8 years. Of those patients who developed lateral compartment OA, 55% (11/20) had a Kellgren-Lawrence score 2 or greater at last radiographic follow-up. Young age and open growth plates were associated with increased incidence of postoperative re-tear (HR: 0.96, CI: 0.93-0.99, p = 0.01). Increased age at diagnosis and BMI ≥ 30 were associated with increased risk of progression to lateral compartment OA on final radiographs. Conclusion: Patients with a surgically treated lateral discoid meniscus tear had a high rate of recurrent meniscus tear at long-term follow-up (60% at 8 years) that was associated with young age. Approximately 48% of surgically treated patients developed symptomatic lateral compartment OA at eight years from initial presentation. The risk of progression to OA increased with older age at diagnosis and BMI ≥ 30.