Level 2 [mid-level] evidence

Arthroscopic surgery for knee pathology is the most commonly performed orthopedic surgery worldwide despite growing evidence from multiple clinical trials questioning its efficacy in a variety of clinical settings. A recently published multicenter randomized noninferiority trial in the Netherlands compared early meniscectomy to physical therapy (PT) for adults age 45 to 70 with knee pain and nonobstructive meniscal tear found on magnetic resonance imaging (MRI).1 The primary outcome was change in patient-reported knee function from baseline over 24 months (included data from all interval time points) based on the Subjective Knee Form of the International Knee Documentation Committee (IKDC) with scale from 0 to 100, where 100 represented no functional limitation. Researchers randomly assigned 321 patients to either arthroscopic partial meniscectomy (APM) or sixteen 30-minute sessions of PT over 8 weeks. Patients in the APM group did not undergo postoperative PT unless indicated by the surgeon for treatment failure or functional decline. 

Participants in each group were similar in age (mean 57 years), body mass index (mean 27), and comorbidities. Most had “doubtful” to “minimal” osteoarthritis on plain radiography. Loss to follow-up was lower than predicted at 10%. The crossover rate from the PT group to APM was 29% (45 of 141 patients). Both groups had an overall improvement from baseline during the 2 years of follow-up. In both the as-treated and intention-to-treat analyses, PT met the predefined noninferiority margin when data from 3, 6, 12, and 24 months were combined. However, PT did not meet the noninferiority threshold at 12 or 24 months when taken individually.

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It is worth pointing out that the language describing the primary outcome was changed from “change from baseline to 24-month follow-up” to “change from baseline over 24-month follow-up.” This is important because the change in knee function from baseline to 24-month follow-up did not meet noninferiority criteria for PT based on the predefined one-tailed analysis (P <.025). Rather than demonstrating overall noninferiority at 24 months as reported, these data may actually point to noninferiority only up until 6 months, which overlaps with the postoperative period of the APM group. However, even when the difference was not within the noninferiority margin, the difference was less than the prespecified minimal clinically important difference of 8 points in the IKDC score. At follow-up, the greatest within-group difference over the 24-month time interval in IKDC score was only 5.7 points. These findings are consistent with those from the METEOR2 trial that found starting with physical therapy and having surgery only if that failed was as effective as immediate surgery in patients with osteoarthritis of the knee. In addition, the FIDELITY3 trial compared arthroscopic surgery to sham surgery with exercises in both groups after the procedure and found no significant differences in outcomes at 12 months, which further questions the value of surgery.

Alan Ehrlich, MD, is a deputy editor for DynaMed, Ipswich, Massachusetts, and assistant clinical professor in family medicine, University of Massachusetts Medical School, Worcester.

DynaMed is a database that provides evidence-based information on more than 3000 clinical topics and is updated daily through systematic surveillance covering more than 500 journals.

References

  1. van der Graaf VA, Noorduyn JCA, Willigenburg, NW, et al; for the ESCAPE Rescue Group. effect of early surgery vs physical therapy on knee function among patients with nonobstructive meniscal tears: the escape randomized clinical trial. JAMA. 2018;320(13):1328-1337.
  2. Katz JN, Chaisson CE, Cole B, et al. The MeTeOR trial (Meniscal Tear in Osteoarthritis Research): rationale and design features. Contemp Clin Trials. 2012;33(6):1189-1196.
  3. Sihvonen R, Paavola M, Malmivaara A, Jarvinen TL. Finnish Degenerative Meniscal Lesion Study (FIDELITY): a protocol for a randomised, placebo surgery controlled trial on the efficacy of arthroscopic partial meniscectomy for patients with degenerative meniscus injury with a novel ‘RCT within-a-cohort’ study design. BMJ Open. 2013;3(3).