Neurophysiology of Weakness and Exercise in Rotator Cuff Tendinopathy

Patient Inclusion Criteria: * pain with passive provocative maneuvers (positive Hawkins or Neer test) * pain with active elevation (positive painful arc) * pain with isometric resisted movements (Jobe's "empty can" test or resisted shoulder external rotation with the arm at the side) * demonstrate weakness (\>10% force deficit in external rotation) Patient Exclusion Criteria: * shoulder surgery on the symptomatic side * positive Spurling test * traumatic shoulder dislocation or instability in the past 3 months * reproduction of shoulder pain with active or passive cervical range of motion * signs of rotator cuff tear (drop-arm test, lag signs, gross external rotation weakness, or positive image findings) * current musculoskeletal, neurologic or cardiovascular compromise Control Inclusion Criteria: * no current or previous shoulder injury * matched for age (within 5 years) and sex * meet Patient Exclusion Criteria (minus musculoskeletal, neurologic, or cardiovascular compromise) Control Exclusion Criteria: * pain with active arm elevation * positive Hawkins, Neer, or Jobe's test