Compression of Myofascial Trigger Points With a Foam Roller or Ball for Exercise-induced Anterior Knee Pain: A Randomized Controlled Trial.

Objective: The study aimed to evaluate the effectiveness of compression of myofascial trigger points (MTrPs) with a foam roller or ball, combined with static stretching of knee muscles, on exercise-induced, anterior knee pain in fitness runners. Design: The research team designed a randomized controlled trial. Setting: The study took place in the Department of Sports Medicine and Rehabilitation Center of the School of Kinesiology at Shanghai University of Sport in Shanghai, China. Participants: A total of 80 participants, 28 males and 52 females with an average age of 37.2 ± 2.9 years, were recruited at the center. Intervention: The participants were randomly assigned to one of 4 groups, with 20 participants in each group: (1) the MG+SG group, which received compression with a foam roller or ball (MG) and static stretching (SG); (2) the MG group, which received compression only; (3) the SG group static, which received static stretching only; or (4) the control group (CG), which attended a 30-min class about nutrition or exercise once a month and received no intervention. For the MG intervention, participants' MTrPs were compressed with a foam roller or ball for 30 minutes once every 5 days for 2 months. After each compression, the MG+SG group received static stretching immediately. Outcome Measures: A visual analog scale (VAS) and a participant's range of motion (ROM) of the knee were assessed at baseline, after 4 weeks of the intervention, immediately postintervention, and at a follow-up at 8 weeks postintervention. The effectiveness of the treatment in the different groups was also compared. Results: Immediately postintervention, 18 participants (90%) in MG+SG group, 12 (60%) in MG group, and 8 (40%) in the SG group were pain free. Compared with those at baseline, the VAS scores of the MG+SG group significantly improved between baseline and postintervention and were unchanged at the eight-week follow-up. In all groups, the VAS scores and ROMs of the knee increased, but only the MG+SG group's values increased significantly. Conclusions: Compression of MTrPs with a foam roller or ball, combined with static stretching, was more effective than either the compression only or static stretching only.