Arthroscopic surgery for degenerative knee: systematic review and meta-analysis of benefits and harms

Thorlund JB, Juhl CB, Roos EM, Lohmander LS · BMJ

Pooling each trial's primary endpoint between three and 24 months gave an effect size for pain of 0.14 (95% CI 0.03 to 0.26), which the authors convert to 2.4 mm (95% CI 0.4 to 4.3) on a 0-100 mm visual analogue scale. Analysed by time, the benefit was 3 to 5 mm at three and six months and absent from then to 24 months. Physical function did not separate (effect size 0.09, 95% CI -0.05 to 0.24). On the harms side, symptomatic deep vein thrombosis occurred at 4.13 events per 1,000 procedures (95% CI 1.78 to 9.60), alongside pulmonary embolism, infection and death.

Population

Nine randomised trials of arthroscopic surgery involving partial meniscectomy, debridement or both in middle-aged and older patients with knee pain and degenerative knee disease, with or without radiographic osteoarthritis, plus nine further studies reporting harms

Intervention

Arthroscopic knee surgery involving partial meniscectomy, debridement, or both

Comparator

Non-operative care, placebo surgery or sham

Limitations

The nine benefit trials mix partial meniscectomy with debridement and lavage, so the pooled estimate is for arthroscopic surgery of the degenerative knee rather than for meniscectomy alone. Harms come from cohort, registry and case-series data, which is the only place they are reported at usable scale but is not randomised. Searches close in August 2014, so the later placebo-surgery follow-ups and the exercise trials are not in it. One author is supported by the Swedish Research Council; the authors completed ICMJE disclosure forms.