Rotator Cuff Impingement Syndrome



  • Compression of rotator cuff tendons and subacromial bursa between the humeral head and the structures comprising the coracoacromial arch and proximal humerus
  • Most common cause of atraumatic shoulder pain in patients >25 years of age
  • Primary symptom is pain that is most severe when the arm is abducted between 60 and 120 degrees (the “painful arc”).
  • Classically divided into three stages:
    • Stage I: acute inflammation, edema, or hemorrhage of the underlying tendons due to overuse (typically in those aged <25 years)
    • Stage II: progressive tendinosis that leads to partial rotator cuff tear along with underlying thickening or fibrosis of surrounding structures (commonly, ages 25 to 40 years)
    • Stage III: full-thickness tear (typically in patients aged >40 years)



  • Shoulder pain accounts for 1% of all primary care visits.
  • Peak incidence of 25/1,000 patients per year occurs in patients aged 42 to 46 years.
  • Impingement responsible for 18–74% of shoulder pain diagnoses

Prevalence of shoulder pain in general population ranges from ~7% to 30%.

Risk Factors

  • Repetitive overhead motions (throwing, swimming)
  • Glenohumeral joint instability or muscle imbalance
  • Acromioclavicular arthritis or osteophytes
  • Thickened coracoacromial ligament
  • Shoulder trauma
  • Increasing age
  • Smoking

General Prevention

  • Proper throwing and lifting techniques
  • Proper strengthening to balance rotator cuff and scapula stabilizer muscles

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