Better outcome from arthroscopic partial meniscectomy than skin incisions only? A sham-controlled randomised trial in patients aged 35–55 years with knee pain and an MRI-verified meniscal tear

Abstract

ObjectiveCompare arthroscopic partial meniscectomy to a true sham intervention.MethodsSham-controlled superiority trial performed in three county hospitals in Denmark comparing arthroscopic partial meniscectomy to skin incisions only in patients aged 35–55 years with persistent knee pain and an MRI-confirmed medial meniscus lesion. A computer-generated table of random numbers generated two comparison groups. Participants and outcome assessors were blinded to group allocation. Exclusions were locking knees, high-energy trauma or severe osteoarthritis. Outcomes were collected at baseline, 3 and 24 months. We hypothesised no difference between groups. The primary outcome was the between-group difference in change from baseline to 2 years in the mean score across all five normalised Knee injury and Osteoarthritis Outcome Score (KOOS) subscales (KOOS5).ResultsForty-four patients (of the estimated 72) underwent randomisation; 22 in each group. Sixteen participants (36%) were non-blinded and eight participants (36%) from the sham group crossed over to the surgery group prior to the 2-year follow-up. At 2 years, both groups reported clinically relevant improvements (surgery 21.8, skin incisions only 13.6), the mean difference between groups was 8.2 in favour of surgery, which is slightly less than the cut-off of 10 prespecified to represent a clinically relevant difference; judged by the 95% CI (−3.4 to 19.8), a possibility of clinically relevant difference could not be excluded. In total, nine participants experienced 11 adverse events; six in the surgery group and three in the skin-incisions-only group.ConclusionWe found greater improvement from arthroscopic partial meniscectomy compared with skin incisions only at 2 years, with the statistical uncertainty of the between-group difference including what could be considered clinically relevant. Because of the study being underpowered, nearly half in the sham group being non-blinded and one-third crossing over to surgery, the results cannot be generalised to the greater patient population.Trial registration numberNCT01264991.

Validity and generalizability of findings of randomized controlled trials on arthroscopic partial meniscectomy of the knee

“…Altogether, 7 randomized controlled trials (RCTs) fulfilling the inclusion criteria were found (Table ) . Of the 7 RCTs, 5 have been carried out in the Nordic countries, one in USA, and one in South Korea.…”

“…All studies reported the proportion of patients crossing over to surgical treatment, but none of the studies reported reasons for the crossover. In 5 trials, the proportions of patients crossing over to surgery were highest and varied between 19 and 36 percent. No trial reported prespecified criteria for crossing over to surgical treatment.…”

“…None of the studies based their primary conclusions on the actualized intervention contrast between the treatment arms. Double blinding was indicated in the trial by Sihvonen et al and by Roos et al for the assessment of biological effectiveness of APM, while other trials assessed effectiveness in real‐world healthcare circumstances, where the patients and practitioners are not blinded.…”

“…Other trials used outcomes primarily intended for patients with knee osteoarthritis or trauma. The trials reported outcomes according to the protocols published a priori at the ClinicalTrials.gov or according to the methods sections of their papers . All trials used similar follow‐up time‐points between groups, and appropriate statistical analyses.…”

“…Cochrane CENTRAL, Ovid MEDLINE, and Web of Science databases till October 2017 were used to find the eligible articles by the author, who checked the search findings to exclude misclassifications (Appendix ). Finally, the very recently published RCT was added to the material …”