Effects of backward walking exercise using lower body positive pressure treadmill on knee symptoms and physical function in individuals with knee osteoarthritis: a protocol for RCT

Objectives: The primary aim is to compare the effects of backward walking exercise to forward walking exercise on knee pain, knee functions, and thigh muscle strength in individuals with mild to moderate knee osteoarthritis using lower body positive pressure, in addition to mobility functions, balance, and self-reported health status. Methods: The study is a single blind randomized clinical trial with two independent groups. This study will enroll 26 participants with mild to moderate knee osteoarthritis. The participants will be randomized into either experimental group (backward walking exercise) or control group (forward walking exercise). Both groups will use lower body positive pressure treadmill for walking exercise. Both groups will perform regular conventional exercise and worm-up exercise before walking exercise. The treatment will be three times a week for six weeks. Walking session will be up to 30 min each session. Data collection will be collected during pre- and post- intervention including primary outcomes including numeric pain rating scale (NPRS), knee injury and osteoarthritis outcome score (KOOS), and thigh muscle strength test. The secondary outcomes include five times sit to stand test (FTSTS), 3-meter backward walk test (3MBWT), timed up and go test (TUG), four square step test (FSST), functional reach test (FRT), 10-meter walk test (10-MWT), six minute walk test (6MWT), medical outcomes study short form 12 (SF-12), patient health questionnaire -9 (PHQ-9), and rapid assessment of physical activity (RAPA). An independent t-test will be used to evaluate the effect of treatment on the outcome measures. Results: Not applicable. Conclusion: Using lower body positive pressure may have promising results against knee osteoarthritis. Moreover, walking backward exercise using lower body positive pressure might add more benefits to individuals with knee osteoarthritis and help clinicians in decision making. Trial registration: This study was registered in ClinicalTrails.gov (ID: NCT05585099).