Evaluation of an exercise concept focusing on eccentric strength training of the rotator cuff for patients with subacromial impingement syndrome

Objective: To evaluate the effect on pain intensity and function of an exercise concept focusing on specific eccentric strength training of the rotator cuff in patients with subacromial impingement syndrome. Design: Single-subject research design with baseline and treatment phases (AB design). Setting: Home-based training programme supervised and supported by visits to physiotherapy clinic. Subjects: Ten patients, mean (SD) age 54 (8.6) years, symptom duration 12 (9.1) months. Intervention: Daily eccentric strengthening exercises of the rotator cuff during 12 weeks. Main measures: Primary outcome measures: Pain intensity, assessed with a visual analogue scale, and function, using the Patient-Specific Functional Scale. Secondary outcome measures: Shoulder function evaluated with the Constant score, and shoulder-related quality of life evaluated with the Western Ontario Rotator Cuff Index. Results: Pain intensity decreased significantly in eight of the ten subjects. Function improved significantly in all ten subjects. Constant score increased in nine subjects and Western Ontario Rotator Cuff Index increased in seven subjects. Mean Constant score for the whole group increased significantly from 44 to 69 points (P = 0.008). Mean Western Ontario Rotator Cuff Index increased from 51 to 71% (P = 0.021). Conclusion: A 12-week eccentric strengthening programme targeting the rotator cuff and incorporating scapular control and correct movement pattern can be effective in decreasing pain and increasing function in patients with subacromial impingement syndrome. A randomized controlled trial is necessary to provide stronger evidence of the method.