2. PLAN OF STUDY 2.1) Assessment 1: Patients selected for study are those referred to our outpatient musculoskeletal physiotherapy with a diagnosis of impingement syndrome grade II and grade III. All will be evaluated by a blinded investigator, who uses the Visual Analogue Scale (VAS), the rating scale of Constant and University of California, Los Angeles (UCLA) shoulder rating scale, and measurement of rotator cuff muscle force (external and internal rotation) and shoulder elevation.