Interventions for osteoarthritis pain: A systematic review with network meta-analysis of existing Cochrane reviews

To conduct a network meta-analysis comparing all treatments for osteoarthritis (OA) pain in the Cochrane Library.

The Cochrane Library and Epistemonikos were searched for randomized controlled trials (RCTs) about treatments for hip and knee OA. We constructed 17 broad categories, comprising drug treatments, exercise, surgery, herbs, orthotics, passive treatments, regenerative medicine, diet/weight loss, combined treatments, and controls. In addition to a full network analysis, we compared the direct/indirect effects, and studies with shorter-/longer follow-up. CINeMA software was used for assessing confidence in network meta-analysis estimates.

We included 35 systematic reviews including 445 RCTs. There were 153 treatments for OA. In total, 491 comparisons were related to knee OA, less on hip OA, and only nine on hand OA. Six treatment categories showed clinically significant effects favoring treatment over control on pain. "Diet/weight loss" and "Surgery" had effect sizes close to zero. The network as a whole was not coherent. Of 136 treatment comparisons, none were rated as high confidence, six as moderate, 13 as low, and 117 as very low.

Direct comparison of different available treatment options for OA is desirable, however not currently feasible in practice, due to heterogeneous study populations and lack of clear descriptions of control interventions. We found that many treatments were effective, but since the network as a whole was not coherent and lacked high confidence in the treatment comparisons, we could not produce a ranking of effects.