The Dose-Response Effect of Medical Exercise Therapy on Impairment in Patients with Unilateral Longstanding Subacromial Pain

OBJECTIVES: The primary aim of this study was to investigate the effect of medical exercise therapy in shoulder impingement patients, along with possible correlations between impairment variables. STUDY DESIGN: A prospective unblended randomized clinical trial. METHODS: Over four months, 61 participants were randomly assigned into a high-graded exercise therapy group (HD) (n=31) and into a low-graded exercise therapy group (LD) (n=30). Prognostic variables were similar between the groups at baseline. Five (8%) patients dropped out during the treatment period, and another four (6%) dropped out before followup. Pain was a composite score of a visual analogue scale (VAS). Isometric strength was measured during four resisted break tests on the shoulder. Function was measured by means of a functional assessment questionnaire (Shoulder Rating Questionnaire, SRQ). Both groups trained three times per week for twelve weeks, with tests pre- and posttraining and six months follow-up. RESULTS: The HD group achieved significantly (p < 0.05) better outcome effects than the LD group for pain, range of motion, isometric functional strength and function, but both groups increased function from pretest to posttest. CONCLUSIONS: In patients with uncomplicated subacromial pain syndrome, medical exercise therapy is an efficient treatment alternative, where high-grade doses should be emphasized. A major limitation is that the measurements were not undertaken by another person than the treating physiotherapists.