Effectiveness of scapular mobilization in people with subacromial impingement syndrome: A randomized controlled trial

Background: Scapular mobilization is a manual therapy technique widely used in the management of musculoskeletal disorders of the shoulder. Objective: To determine the effects of scapular mobilization in addition to an exercise program in people with subacromial impingement syndrome (SIS). Methods: Seventy-two adults with SIS were randomly allocated to 1 of 2 groups. The control group (n=36) participated in a 6-week exercise program, and the intervention group (n = 36) participated in the same exercise program plus passive manual scapular mobilization. Both groups were assessed at baseline and 6 weeks (end of treatment). The primary outcome measure was upper limb function assessed using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire. Secondary outcome measures were the Constant-Murley questionnaire, pain (visual analog scale [VAS]), and scapular upward rotation. Results: All participants completed the trial. The between-group difference in DASH was -1.1 points (Cohen d = 0.05; p = 0.911), Constant-Murley 2.1 points (Cohen d = 0.08; p = 0.841), VAS rating of pain at rest -0.1 cm (Cohen d = 0.05; p = 0.684), and VAS rating of pain during movement -0.2 cm (Cohen d = 0.09; p = 0.764); scapular upward rotation at rest (arm by the side) was 0.6° (Cohen d = 0.09; p = 0.237), at 45° shoulder abduction was 0.8° (Cohen d = 0.13; p = 0.096), at 90° was 0.1° (Cohen d = 0.04; p = 0.783), and at 135° was 0.1° (Cohen d = 0.07; p = 0.886). Most differences were in favor of the intervention group; however, the effect sizes were weak and not statistically significant. Conclusions: In the short-term, the addition of scapular mobilization did not provide significant clinical benefits in terms of function, pain or scapular motion in participants with SIS. Trial registration: Brazilian registry of clinical trials UTN number U1111-1226-2081. Registered February 25, 2019.