Change in patient-reported outcomes in patients with and without mechanical symptoms undergoing arthroscopic meniscal surgery: A prospective cohort study.

Objective: Patients with degenerative or traumatic meniscal tears are at high risk of developing knee osteoarthritis. We investigated if younger (≤40 years) and older (>40 years) patients with preoperative mechanical symptoms (MS) improved more in patient-reported outcomes after meniscal surgery than those without MS.
Design: Patients from Knee Arthroscopy Cohort Southern Denmark (KACS) undergoing arthroscopic surgery for a meniscal tear completed online questionnaires before surgery, and at 12 and 52 weeks follow-up. Questionnaires included self-reported presence of MS (i.e., sensation of catching and/or locking) and the Knee injury and Osteoarthritis Outcome Score (KOOS). We analyzed between-group differences in change in KOOS ₄ from baseline to 52 weeks, using an adjusted mixed linear model.
Results: 150 younger patients (mean age 31 (SD 7), 67% men) and 491 older patients (mean age 54 (SD 9), 53% men) constituted the baseline cohorts. Patients with MS generally had worse self-reported outcomes before surgery. At 52 weeks follow-up, younger patients with preoperative MS had improved more in KOOS ₄ scores than younger patients without preoperative MS (adjusted mean difference 10.5, 95% CI: 4.3, 16.6), but did not exceed the absolute postoperative KOOS ₄ scores observed for those without MS. No difference in improvement was observed between older patients with or without MS (adjusted mean difference 0.7, 95% CI: -2.6, 3.9).
Conclusions: Younger patients (≤40 years) with preoperative MS experienced greater improvements after arthroscopic surgery compared to younger patients without MS. Our observational study result needs to be confirmed in randomized trials.
(Copyright © 2018 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)