Exercise for osteoarthritis of the knee

Fransen M, et al. · Cochrane Database of Systematic Reviews

High-quality evidence from 44 trials (3,537 participants) that land-based therapeutic exercise reduced knee OA pain immediately after treatment (SMD -0.49, 95% CI -0.39 to -0.59), equivalent to 12 points (95% CI 10 to 15) against a control-group pain of 44 on a 0-100 scale. Moderate-quality evidence from 44 trials (3,913 participants) that it improved physical function (SMD -0.52, 95% CI -0.39 to -0.64), about 10 points (8 to 13), and high-quality evidence from 13 studies (1,073 participants) that it improved quality of life (SMD 0.28, 95% CI 0.15 to 0.40), about 4 points (2 to 5). Benefit was sustained at least two to six months after formal treatment ended, and withdrawal was as common in the exercise arms as in the controls (14% against 15%, OR 0.93). The reviewers call the effect moderate immediately and small at two to six months, and comparable with published estimates for simple analgesics and non-steroidal anti-inflammatory drugs taken for knee pain.

Population

54 RCTs in people with knee OA

Intervention

Land-based therapeutic exercise (strengthening, aerobic, mixed)

Comparator

No exercise / usual care

Limitations

Participants cannot be blinded to an exercise programme, and physical function and quality of life were self-reported. Symptom outcomes only; no structural endpoint anywhere in the review. The programmes were heterogeneous enough that the reviewers state no specific recommendation can be made about optimal dose - frequency, intensity or duration.