A Study on the Effects of Lateral-Wedge Insoles on Plantar-Pressure Pattern for Medial Knee Osteoarthritis Using the Wearable Sensing Insole

Patients with knee osteoarthritis have a unique plantar-pressure pattern during walking, and lateral-wedge insoles are one of the treatment options. Participants were randomly assigned to either the lateral-wedge insole group or the ordinary insole group. The Visual Analog Scale (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and plantar-pressure test scores were evaluated at the baseline and at 20 weeks. Plantar pressure data were collected using a pressure insole with 89 sensing locations. In the ordinary insole group, the function and total WOMAC scores decreased significantly (function score, 24.8 (baseline) to 16.5 (week 20); total score, 34.9 (baseline) to 24.6 (week 20)). During walking, the transverse width of the center of pressure as a percentage of foot width (%Trans) significantly increased in the ordinary insole group (baseline, 6.3%; week 20, 14.8%). In addition, the values of partial foot pressure as a percentage of body weight (%PFP) on the forefoot (baseline, 30.3%; week 20, 39.2%) and heel (baseline, 28.1%; week 20, 16.9%) also increased significantly in the ordinary insole group. Significant group-by-time interaction effects were observed for partial foot pressure per body weight in the forefoot (p = 0.031) and heel (p = 0.024). In the ordinary insole group, the plantar pressure on the heel significantly decreased (p = 0.011) and that on the forefoot significantly increased (p = 0.023). In contrast, plantar pressure remained stable in all regions in the lateral-wedge insole group. Thus, lateral-wedge insoles may protect against plantar pressure deterioration in patients with knee osteoarthritis.

Automated summary

Patients with knee osteoarthritis have a unique plantar-pressure pattern during walking, and lateral-wedge insoles may protect against plantar pressure deterioration in these patients. In a study comparing lateral-wedge insoles with ordinary insoles, it was found that the ordinary insole group experienced significant decreases in function and total WOMAC scores, and significant increases in %Trans, %PFP on the forefoot, and %PFP on the heel. In contrast, plantar pressure remained stable in all regions in the lateral-wedge insole group.