Lateral wedge arch support does not reliably reduce knee load in medial knee osteoarthritis
A meta-analysis of nine studies (n=337) showed an overall pooled reduction in the first peak external knee adduction moments (EKAM; standard mean difference [SMD], -0.22; 95 percent CI, -0.37 to -0.07; p=0.005) due to LWAS.
On the other hand, subgroup analyses showed that LWAS significantly improved first peak EKAM when compared against neutral insoles (SMD, -0.27; -0.51 to -0.04; p=0.02) but not against control shoes (SMD, -0.17; -0.37 to 0.03; p=0.10) or flat insoles (SMD, -0.39; -1.28 to 0.49; p=0.39)
LWAS also showed an overall significant reduction in second peak EKAM (SMD, -0.26; -0.47 to -0.06; p=0.01) according to a meta-analysis of four studies.
However, subsequent subgroup analysis showed that LWAS improved second peak EKAM only against the shoe-only control (SMD, -0.25; -0.48 to 0.17; p=0.03) and not against neutral insoles (SMD, -0.30; -0.76 to 0.17; p=0.21).
Knee adduction angular impulse (KAAI) was analysed in six studies. Overall pooled estimates showed significant declines in KAAI using LWAS (SMD, -0.21; -0.39 to -0.02; p=0.03).
Subsequent subgroup analyses again showed no statistically significant improvements in KAAI as a result of LWAS use compared with neutral insoles (SMD, -0.23; -0.61 to 0.15; p=0.23) or shoe-only controls (SMD, -0.20; -0.41 to 0.01; p=0.06).
The meta-analysis included articles that compared the efficacy of LWAS against controls (control shoe, neutral insole or flat insole) in adults with medial knee osteoarthritis. The databases of Google Scholar, Cochrane Library, Wiley Online Library, Web of Science, Embase and Medline were accessed. Quality of the studies was assessed using the Quality Index.