Progressive strengthening exercises for subacromial impingement syndrome.

OBJECTIVE: To compare the effectiveness of specific exercises for the rotator cuff and scapular stabilizers with unspecific exercises in the treatment of subacromial impingement syndrome.

DESIGN: Randomized controlled trial with 3 months of follow-up. Participants and the single assessor were blinded to group assignment. Sample size was calculated with 80% power to show a minimum clinically important difference of 10% on the Constant–Murley score at P ≤ 0.05.

SETTING: Tertiary study in Linköping, Sweden, between January 2008 and February 2010.

PARTICIPANTS: Patients on the waiting list for arthroscopic subacromial decompression were recruited from the Department of Orthopaedics at University Hospital. Inclusion criteria were 30-65 years of age; a 6-month duration of the current episode of pain in the proximal-lateral aspect of the upper arm; lack of response to conservative treatment; and positive results on the Neer test and 2 of the following tests: Hawkins-Kennedy, Jobes, and Patte. Exclusion criteria were other conditions such as malignancy, osteoarthritis, osacromiale, joint instability, frozen shoulder,and symptoms originating in the spine; a history of fractures or surgery in the shoulder complex; and corticosteroid injections to the shoulder within the previous 3 months.

INTERVENTION: Both the intervention and control groups received a subacromial corticosteroid injection at the inclusion visit. Exercises supervised by a physiotherapist commenced 2 weeks after the injection. There were 7 sessions over the next 2 weeks, and participants were instructed to do the exercises daily at home for 12 weeks and to keep exercise diaries. The control exercise program included 6 unspecific nonprogressive movement and stretching exercises for the neck and shoulder with no external load. Exercises for the intervention group were 2 eccentric exercises for the rotator cuff, 3 concentric/eccentric exercises for the scapula stabilizers, and a posterior shoulder stretch. The strengthening exercises were repeated 15 times in 3 sets, twice daily, for 8 weeks, with the stretch repeated every set. During weeks 9 to 12, the exercises were repeated once a day. The exercises progressed with increasing external load modified by the level of pain that the patient reported. Good posture was emphasized. After 12 weeks, continuation of the exercises for 2 months was recommended.

MAIN OUTCOME MEASURES: The main outcome measure was shoulder function and pain assessed after 3 months by the Contant–Murley score (0-100, worst to best shoulder function). Additional measures were the disabilities of the arm,shoulder, and hand (DASH) score and visual analog pain scores. The patients rated their global impression of the effectiveness of their treatment, and they were asked whether they felt that they still needed arthroscopic subacromial decompression.The analysis included 97 of 102 randomized patients.

MAIN RESULTS: After 3 months were greater for the intervention group than the control group (72.5 vs 52.5) with the mean difference in change favoring the intervention group (mean difference,15 points; 95% confidence interval [CI], 8.5-20.6). The intervention group also improved more on the DASH score (mean difference between groups, 8 points; 95% CI, 2.3-13.7) and on pain at night but not on pain during activity or at rest. The groups did not differ in changes in health-related quality of life. More patient sin the intervention group than the control group reported a successful outcome of treatment (35/51 vs 11/46; odds ratio, 7.6; 95% CI, 3.1-18.9) and fewer chose subsequent surgery (10/51 vs 29/46; odds ratio, 7.7; 95% CI, 3.1-19.4).

CONCLUSIONS: A 3-month specifically tailored progressive strengthening exercise program was more beneficial in improving shoulder function in subacromial impingement syndrome than were non specific exercises. More patients felt their treatment was successful, and fewer subsequently chose surgery.