I. The three anatomic layers of the shoulder:

  1. "Power" layer: Outermost--Includes deltoid, rhomboid, pec major, trapezius
  2. "Dynamic stability" layer: Middle--Includes rotator cuff mm. (supraspinatus, infraspinatus, teres minor, subscapularis)
  3. "Static stability" layer: Inner: Consists of the joint capsule which includes the glenohumeral ligaments; too tight = Adhesive Capsulitis; too loose = Instability

II. Common causes of shoulder sx

  1. Fracture
    1. More likely in elderly
  2. Dislocation
    1. More likely in young
  3. Instability--Can cause dislocation
    1. Classified into two categories--"AMBRI" and "TUBS"
    2. "AMBRI"--these pts may have general ligamentous laxity
      1. Atraumatic
      2. Multidirectional
      3. Bilateral
      4. Rehab is the best tx
      5. Inferior capsular shift is the preferred surgery if surgery is needed
    3. "TUBS"
      1. Traumatic
      2. Unidirectional
      3. Bankart lesion is common (detachment of labrum off glenoid)
      4. Surgery usually needed; results are very good
      5. Other notes:
        1. Those caused by a direct blow are more likely to recur than those caused by twisting or abduction
        2. Young pts-immobilize 6-12wks then ROM/strength exercises
        3. Pts >50yo; higher risk of loss of mobility, so immobilize less time
    4. Points of hx to clarify: h/o trauma, position of arm when went out of joint, whether relocation was required, whether previous dislocation occurred
    5. NOTE--Posterior dislocations are rare, BUT can be missed on plain AP x-rays of shoulder; often can be seen on axillary view
    6. NOTE--Make sure to check for axillary nerve damage in pts with dislocation of shoulder (deltoid strength; sensation over lateral shoulder)
  4. Impingement
    1. Consists of impingement of rotator cuff, subacromial bursa, and/or biceps tenden between the humeral head and the "coracoacromial arch" (acromian, coracoacromial ligament, and AC joint)
    2. Can be due to instability, to natural shape of the acromion, or to spurs on undersurface of the acromion or AC joint
    3. Supraspinatus is us. the first structure to be impinged upon
    4. Hx-Usually pain w/overhead activity, radiating to deltoid +/- biceps
    5. Px-Passive ROM is usually normal though pain with abduction of shoulder
    6. Tx-Stop offending activities; ice; NSAIDs (may help to shrink the cuff); Physical Therapy to strengthen humeral head depression; Injections of the subacromial bursa (see below); Surgery (acromioplasty) as last resort.
  5. Rotator cuff tears
    1. More common in elderly
    2. Can be a result of impingement syndrome
  6. Arthritis of glenuhumeral joint
    1. Osteoarthritis of GH rarer than osteoarthritis at other joints
    2. Inflammatory arthritis can occur
  7. Acromioclavicular joint problems
    1. Osteoarthritis
    2. Traumatic separation
  8. Adhesive capsulitis, aka "Frozen Shoulder"
    1. Peak incidence 40-60yo
    2. Risk factors include diabetes mellitus
    3. Clinical presentation includes stiffness, pain (often worse at night), and loss of both active and passive ROM
    4. Generally no h/o sig. injury
    5. Often self-limited but lasts for many years, gradually improving
    6. Workup-X-rays are unrevealing; MRI not useful except to r/o rotator cuff tear
    7. Tx-Stretching, intra-articular steroids, surgical release (rarely done), radiation therapy
    8. Glenohumeral steroid injections ass'd with sig. greater improvements in pain and disability scores at 6wks than physiotherapy in a randomized trial in 93 pts with adhesive capsulitis; combination of steroid injection + physiotherapy not sig. better than either alone (Arth. Rheum. 48:829, 2003--JW)
  9. Bicipital tendinitis
    1. Can be caused by impingement sd.
    2. Can result in bicipital tears
  10. Labral tears
    1. e.g. "SLAP" lesion, at insertion of bicipital tendon into glenoid
    2. More common in young
  11. Cervical disc herniation
    1. Distribution and nature of symptoms aid in diagnosis, e.g. paresthesias in fingers
    2. Sx usually do not change with motion of shoulder
  12. Neoplasm (usually metastatic)
  13. Thoracic outlet syndrome
    1. Often said to involve loss of distal pulses in UE with elevation
    2. "Diagnosis of exclusion"

III. Exam of the shoulder

  1. Inspection
    1. For asymmetry and atrophy
    2. Scapular winging (indicates weakness of serratus anterior e.g. from injury to long thoracic n.)
  2. Palpation
    1. Bones
    2. Muscles
    3. Ant-lat subacromial area for impingement
  3. Strength
    1. Subscapularis--"Lift off" test--UE held behind back, horizontally with elbow extended, palm up, have pt push up with palm against resistance.
    2. Infraspinatus/Teres Minor (external rotation of the shoulder)
      1. Weakness significantly associated with rotator cuff tear on arthroscopy (Lancet 357:769, 2001--AFP)
    3. Supraspinatus
      1. Upper extremity held in front horizontally with elbow extended, palm down, have pt push up with dorsal hand against resistance
      2. Weakness significantly associated with rotator cuff tear on arthroscopy (Lancet 357:769, 2001--AFP)
  4. Stability
    1. "Relocation test"--Pt supine, shoulder in 90' abduction & ext. rotation; "various degrees of abduction are evaluated while anterior stress is applied by the examiner's hand to the posterior part of the humerus. If this produces pain or apprehension, posterior-directed force is applied to the humerus to relocate the humeral head in the glenohumeral joint while the shoulder is placed in abduction and external rotation. The posteriorly directed stress used to relocate the humerus is then released; a feeling of apprehension or subluxation on the part of the patient indicates anterior instability" (quote from Campell's Operative Orthopaedics, 9th ed.)
    2. "Sulcus sign"--Look for sulcus @ shoulder when you pull down on arm held relaxed at pt's side
    3. "Apprehension test"--Pt supine, shoulder in 90' abduction, gradually externally rotate shoulder.  This will put stress on ligaments that normally stop shoulder from dislocating anteriorly.  If there is instability pt may feel like shoulder is going to dislocate; this "apprehension" on the part of the pt is a "positive" test.
  5. Range of motion
    1. Check the following:
      1. Abduction
      2. Internal rotation (hand behind back, elbow flexed, reach up to try to touch scapula)
      3. External rotation--Best done with pt supine
    2. Checking active vs. passive ROM
      1. Check active 1st--if it's normal, no need to check passive
      2. Active ROM us. normal in Impingement Syndrome
      3. Active ROM us. limited in Rotator Cuff Tears or Adhesive Capsulitis
      4. Passive ROM us. normal with Rotator Cuff Tears; us. limited (rotation more so than abduction) with Adhesive Capsulitis
  6. Special testing
    1. "Impingement test"--???
    2. "Biceps tension test"--Resisted forward flexion of the shoulder with elbow extended and in supination

IV. Shoulder radiology

  1. AP view
    1. Normally should see 6mm between umeral head & acromion; if less suggests rotator cuff tear
    2. Look for DJD changes
    3. Look for spurring on underside of acromion that might indicate tendency toward impingement sd.
  2. Axillary view
    1. Looking up through axilla
    2. Done to assess for instability
    3. Can also detect glenoid fx missed on other views
  3. Outlet view
    1. PA but 45' off laterally--looking from post-medial to ant-lateral; pt with arm passively held at their side, holding a weight
    2. Good for viewing acromion; can detect the different acromion "types" (I, II, III)--distinguished according to how much downward deflection there is as the acromion curves around; higher amounts ass'd with impingement sd.
  4. Scapular "Y" view
  5. MRI can overread DJD and biceps injuries and miss partial rotator cuff tears
  6. Ultrasound is good for complete rotator cuff tears; not too sensitive for partial tears

V. Shoulder injections

  1. Subacromial injection with local anesthetic plus steroid--Used for therapeutic purposes but also works as a diagnostic tool (for impingement syndrome)
  2. Shoulder joint injection--Used to tx adhesive capsulitis; us. done under fluoroscopy