Is Anterior Cruciate Ligament Reconstruction Effective in Preventing Secondary Meniscal Tears and Osteoarthritis?

Background: Reconstruction of anterior cruciate ligament (ACL) tears may potentially prevent the development of secondary meniscal injuries and arthritis. Purpose/Hypothesis: The purpose of this study was to (1) evaluate the protective benefit of ACL reconstruction (ACLR) in preventing subsequent meniscal tears or arthritis, (2) determine if earlier ACLR (<1 year after injury) offers greater protective benefits than delayed reconstruction (≥1 year after injury), and (3) evaluate factors predictive of long-term sequelae after ACLR. The hypothesis was that the incidence of secondary meniscal tears, arthritis, and total knee arthroplasty (TKA) would be higher in patients treated nonoperatively after ACL tears than patients treated with surgical reconstruction. Study Design: Cohort study; Level of evidence, 3. Methods: This retrospective study included a population-based incidence cohort of 964 patients with new-onset, isolated ACL tears between 1990 and 2000 as well as an age- and sex-matched cohort of 964 patients without ACL tears. A chart review was performed to collect information related to the initial injury, treatment, and outcomes. A total of 509 patients were treated with early ACLR, 91 with delayed ACLR, and 364 nonoperatively. All patients were retrospectively followed (range, 2 months to 25 years) to determine the development of subsequent meniscal tears, arthritis, or TKA. Results: At a mean follow-up of 13.7 years, patients treated nonoperatively after ACL tears had a significantly higher likelihood of developing a secondary meniscal tear (hazard ratio [HR], 5.4; 95% CI, 3.8-7.6), being diagnosed with arthritis (HR, 6.0; 95% CI, 4.3-8.4), and undergoing TKA (HR, 16.7; 95% CI, 5.0-55.2) compared with patients treated with ACLR. Similarly, patients treated with delayed ACLR had a higher likelihood of developing a secondary meniscal tear (HR, 3.9; 95% CI, 2.2-6.9) and being diagnosed with arthritis (HR, 6.2; 95% CI, 3.4-11.4) compared with patients treated with early ACLR. Age >21 years at the time of injury, articular cartilage damage, and medial/lateral meniscal tears were predictive of arthritis after ACLR. Conclusion: Patients treated with ACLR have a significantly lower risk of secondary meniscal tears, symptomatic arthritis, and TKA when compared with patients treated nonoperatively after ACL tears. Similarly, early ACLR significantly reduces the risk of subsequent meniscal tears and arthritis compared with delayed ACLR.