Shoulder rotator strength in patients with stage I-II subacromial impingement: relationship to pain, disability, and quality of life.

The purpose of this study was two-fold: to determine the shoulder rotator strength in patients with stage I and II subacromial impingement syndrome and to explore its relationship with pain, disability, and quality of life. Thirteen patients with at least 2 positive tests (Neer, Hawkins, painful arc) on the dominant side and 25 unaffected control subjects were included. All individuals had an intact rotator cuff bilaterally, as evaluated by sonography. Isokinetic testing of the shoulder internal and external rotators was performed using Biodex System 3 during concentric/concentric shoulder rotations at a velocity of 60 degrees /s in the scapular plane. The Shoulder Pain and Disability Index, Simple Shoulder Test, and Nottingham Health Profile were self-reported by all subjects. Peak torque values of patients were found to be indifferent from those of controls'. External and internal rotation strength were negatively correlated with pain (r = .63, r = .66, P < .05). In spite of shoulder pain and disability, general health in stage I and II impingement patients did not show any deterioration.