Effects of exercise therapy on joint instability in patients with osteoarthritis of the knee: A systematic review

Kawabata S, Murata K, Nakao K, Sonoo M, Morishita Y, Oka Y, Kokubun T, Kanemura N, et al. · Osteoarthritis and Cartilage Open

Training aimed specifically at knee instability produced no additional benefit over muscle maintenance and strength training on instability ratings. Exercise therapy for knee osteoarthritis did influence muscle strength and pain, but the instability-targeted component added nothing measurable on top. One signal survives the null: stabilisation therapy tended to help patients who had many instability episodes and already had strong muscles, which led the authors to suggest that for patients with weak muscles, strengthening before stabilisation work may be what adds the value.

Population

6 studies of patients with knee osteoarthritis and joint instability, from 14 screened across PubMed, Cochrane and the Physiotherapy Evidence Database

Intervention

Exercise therapy aimed at joint instability — muscle maintenance and strength training, plus training specifically targeting knee stabilisation through proprioceptive, neuromuscular, agility and perturbation work

Comparator

General exercise therapy or usual care

Limitations

Six studies, of which only two were pooled, and publication bias could not be assessed because so little has been published on instability in knee osteoarthritis. The review did not examine fear of movement, varus-valgus alignment or whether one knee or both were affected, any of which could carry the instability signal. Instability itself was largely captured from patient interview rather than measured, which the authors name as the first thing the field needs to fix. Japanese public funding (JSPS KAKENHI Grant-in-Aid for Young Scientists); the authors report no conflicts of interest.