Arthroscopic partial meniscectomy versus placebo surgery for a degenerative meniscus tear Sihvonen

Objective to assess if arthroscopic partial meniscectomy (ApM) is superior to placebo surgery in the treatment of patients with degenerative tear of the medial meniscus. Methods In this multicentre, randomised, participantblinded and outcome assessor-blinded, placebosurgery controlled trial, 146 adults, aged 35–65 years, with knee symptoms consistent with degenerative medial meniscus tear and no knee osteoarthritis were randomised to ApM or placebo surgery. the primary outcome was the between-group difference in the change from baseline in the Western ontario Meniscal Evaluation tool (WoMEt) and Lysholm knee scores and knee pain after exercise at 24 months after surgery. Secondary outcomes included the frequency of unblinding of the treatment-group allocation, participants’ satisfaction, impression of change, return to normal activities, the incidence of serious adverse events and the presence of meniscal symptoms in clinical examination. two subgroup analyses, assessing the outcome on those with mechanical symptoms and those with unstable meniscus tears, were also carried out. results In the intention-to-treat analysis, there were no significant between-group differences in the mean changes from baseline to 24 months in WoMEt score: 27.3 in the ApM group as compared with 31.6 in the placebo-surgery group (between-group difference, −4.3; 95% CI, −11.3 to 2.6); Lysholm knee score: 23.1 and 26.3, respectively (−3.2; −8.9 to 2.4) or knee pain after exercise, 3.5 and 3.9, respectively (−0.4; −1.3 to 0.5). there were no statistically significant differences between the two groups in any of the secondary outcomes or within the analysed subgroups. Conclusions In this 2-year follow-up of patients without knee osteoarthritis but with symptoms of a degenerative medial meniscus tear, the outcomes after ApM were no better than those after placebo surgery. no evidence could be found to support the prevailing ideas that patients with presence of mechanical symptoms or certain meniscus tear characteristics or those who have failed initial conservative treatment are more likely to benefit from ApM. IntrOduCtIOn Arthroscopic partial meniscectomy (APM) is one of the most common orthopaedic operations, with an incidence that has increased steadily from 1990s until late 2010s. Most APMs are carried out in middle-aged and older patients with knee symptoms and degenerative knee disease. 2 Several recent meta-analyses based on randomised controlled trials (RCTs) have failed to show a treatment-benefit of APM over conservative treatment or placebo surgery for these patients. Aligned with the evidence, most guidelines and expert opinion now refrain from recommending APM as the first-line treatment for patients with a degenerative meniscus tear, but still advocate surgery after a failed attempt of conservative treatment. Such recommendations rest on three issues: generally favourable clinical experience, some before-after studies on patients undergoing APM due to persisting symptoms despite conservative treatment 18 and particularly the evidence from three RCTs in which one-third of participants initially allocated to non-surgical treatment opted for crossing over to APM due to persisting knee symptoms or insufficient improvement. After undergoing APM, participants achieved similar outcomes compared with those initially assigned to surgery and those responding favourably to initial non-surgical/conservative treatment. These findings have been interpreted as evidence that APM should be performed after failed conservative treatment. Although such hypotheses might well be true, an alternative accounting can explain the number of crossovers and the beneficial treatment effects of surgery after failed conservative treatment: lack of blinding (participants’ knowledge of not having undergone surgery) may drive conservatively treated patients to request surgery and also make them feel more content with the outcome once having undergone surgery. 24 In addition to patients failing to improve after conservative treatment, other subgroups considered to benefit from APM are those with so-called ‘mechanical symptoms’ or those with ‘unstable’ meniscal tear. 17 28 to cite: Sihvonen r, paavola M, Malmivaara A, et al. Ann Rheum Dis 2018;77:188–195. For numbered affiliations see end of article. Correspondence to professor teppo L n Järvinen, department of orthopaedics and traumatology, University of Helsinki and Helsinki University Hospital, töölö Hospital, topeliuksenkatu 5, Helsinki 00260, Finland; teppo. jarvinen@ helsinki. fi received 19 January 2017 revised 3 April 2017 Accepted 13 April 2017 published online First 18 May 2017 ► http:// dx. doi. org/ 10. 1136/ annrheumdis2017211664 group.bmj.com on February 26, 2018 Published by http://ard.bmj.com/ Downloaded from