Root Repair Versus Partial Meniscectomy for Medial Meniscus Posterior Root Tears: Comparison of Long-term Survivorship and Clinical Outcomes at Minimum 10-Year Follow-up

Background: The importance of repair in medial meniscus posterior root tears (MMPRTs) has been increasingly recognized because it restores hoop tension. However, no study has compared the long-term outcomes between meniscectomy and repair. Hypothesis: Survivorship and clinical outcomes of repair would be better than those of meniscectomy after long-term follow-up. Study Design: Cohort study; Level of evidence, 3. Methods: Between 2005 and 2009, patients with MMPRTs who had been followed up for at least 10 years after partial meniscectomy (n = 18) or pullout repair (n = 37) were recruited. Clinical assessments, including the Lysholm score and International Knee Documentation Committee (IKDC) subjective score, were evaluated preoperatively and at the final follow-up. The final results in each group were compared with the preoperative results, and the final results of the groups were compared. Clinical failure was defined as conversion to total knee arthroplasty (TKA), and the final clinical scores were assessed just before TKA. Kaplan-Meier survival analysis was used to investigate the survival rates of surgical procedures. Results: Mean +/- SD follow-up period was 101.4 +/- 45.9 and 125.9 +/- 21.2 months in the meniscectomy and repair groups, respectively (P = .140). The mean Lysholm and IKDC scores, respectively, in the meniscectomy group were 50.8 +/- 7.7 and 37.6 +/- 7.0 preoperatively and 58.2 +/- 22.1 and 44.4 +/- 19.0 postoperatively (P = .124; P = .240). In the repair group, the mean Lysholm score and IKDC score, respectively, significantly increased from 52.3 +/- 10.9 and 41.0 +/- 9.6 preoperatively to 77.1 +/- 24.0 and 63.7 +/- 20.6 postoperatively (P < .001; P < .001). The final Lysholm and IKDC scores in the repair group were significantly better than those in the meniscectomy group (P = .004; P = .003). In cases of clinical failure, 10 patients (56%) in the meniscectomy group and 8 patients (22%) in the repair group converted to TKA in the follow-up period (P = .016). According to Kaplan-Meier analysis, the 10-year survival rates for the meniscectomy and repair groups were 44.4% and 79.6%, respectively (P = .004). Conclusion: In MMPRTs, root repair was superior to partial meniscectomy in terms of clinical results for at least 10 years of follow-up. From a long-term perspective, repair with restoration of hoop tension is more effective management than meniscectomy.