Lower Positive Body Pressure Walking Significantly Improves Pain and Function In Individuals With Knee Osteoarthritis: A Pilot Randomized Clinical Trial.

Abstract

Objectives: Body weight-supported (BWS) walking therapies, lower-body positive pressure (LBPP) treadmills, or aquatic pool walking could provide a treatment to reduce pain in individuals with knee osteoarthritis (OA). Our objective was to examine the potential benefits of BWS for individuals with knee OA.

Design: Parallel group randomized clinical trial. Forty-nine (n=49) participants, aged above 50 with knee OA, were randomly assigned to 1 of 3 groups: (1) control (n=16), (2) aquatic (n=17), and (3) LBPP (n=16). Interventional groups had two 30-minute walking sessions for 8 weeks. The control group received no active treatment. The primary outcome was the change in Knee Injury and Osteoarthritis Outcome Score (KOOS)-Pain from baseline to 8 weeks. Secondary outcomes included other KOOS subscales, 6-minute walk test (6-MWT), joint kinematics, and serum cytokine concentration.

Results: Forty-one participants completed the trial. Changes in KOOS-Pain from baseline to 8 weeks were statistically significant and clinically relevant in the LBPP group (15.3, 95% CI: 5.0, 25.6). Changes in the other groups were not statistically significant [aquatic 0.9 (95% CI: -7.8, 9.6); and control -3.3 (95% CI: -12.3, 5.7). Post hoc analyses indicated improvements were significantly larger with LBPP. This group improved in 6-MWT (58.9 m, 95% CI: 26.1, 91.7) and most KOOS subscales. Improvements in KOOS-Pain at 8 weeks in the LBPP group were associated with increased knee flexion ( P =0.02). Only the control group had significant increases in IL-1β ( P =0.04) and IL-1RA ( P =0.02) concentration at 8 weeks.

Conclusions: This is the first randomized controlled trial of BWS for knee OA and showed the benefits of LBPP treadmill walking. Future, larger studies should assess the effect size, sustained benefits, and cost-effectiveness.