BACKGROUND & OBJECTIVE
The purpose of this study was to compare the effect of a pain free (NPEE) and painful eccentric exercise (PEE) program for the shoulder on pain, active range of motion (AROM), and shoulder function in those with subacromial pain syndrome (SS). While certain studies find no significant differences between eccentric and concentric exercise in SS, several studies support the EE (eccentric exercise) application. However, there is no evidence on the role of pain during exercise. This study was conducted to elucidate the differing degree of efficacy, if any, between painful vs non-painful EE for SS.
The study design was a prospective, parallel-group, randomized clinical trial which included a total of 22 subjects (11 per group) between 25 and 70 years old. Subjects were referred to a physiatrist, and to rehabilitation services after visiting the medical center with a diagnosis of SS and painful arc upon active lifting of the arm. Exclusion criteria were patients with rotator cuff tears, patients who had undergone surgery of the shoulder in the last 3 months, those with frozen shoulder, shoulder prosthesis, fibromyalgia, or malignant neoplasm, and a history of rheumatic or chronic inflammatory disease.
After baseline testing, subjects were randomly assigned into a non-painful EE group (0mm on the VAS during exercise) or a painful EE group (< 40 mm on the VAS during exercise). The study design employed use of a 4-week EE program comprising 5 training sessions per week, each session lasting approximately 30 minutes. Both groups completed follow-up testing 1 day after completing the EE program.
The results of this study suggest that performing EE with or without pain during exercise results in statistically similar changes in VAS, AROM, and CMS (Constant-Murley Score -“ a shoulder specific functional outcome measure). No statistically significant differences were found