see also:

• orthopaedics in the ED
• the acutely painful elbow
• interscapular thoracic back pain

• shoulder pain is a very common presentation to the ED
• one needs to differentiate local injury or inflammation to that from referred pain

• a painful stimulus involving the diaphragm or the mediastinum commonly results in referred shoulder tip pain, usually on the same side this may be due to life threatening ruptured ectopic pregnancy with haemoperitoneum - urgent bedside FAST USS if this is a possibility
• referred pain may also originate in the cervical nerves such as with cervical disc prolapse
• the patient with referred pain to the shoulder generally has full range of movement of the shoulder without increase in pain

• ischaemic chest pain - see the adult patient with chest pain in the ED
• gastro-oesophageal reflux
• diaphragmatic pleural inflammation - eg pulmonary embolism (PE), pneumonia
• diaphragmatic irritation from abdominal causes
  • free fluid in the abdomen (pain often worse on lying down as fluid flows onto diaphragm)
    • eg. ruptured ectopic pregnancy, blunt abdominal trauma, etc
  • air in the abdomen - eg. post-laparoscopy, perforated viscus
  • subcapsular hepatic conditions (palpation may be non-tender or only mildly tender but can worsen the shoulder pain)
    • amoebic abscess in returned travellers ~8-12 weeks after infection, may have preceding mild diarrhoea
    • pyogenic hepatic abscess
  • pyogenic subphrenic abscess (usually a complication of intrabdominal sepsis)
  • cholecystitis (generally has +ve Murphys sign with very tender RUQ)
• cervical disc prolapse
• cervical radiculopathy

• mainly elderly patients
• important to exclude early - suspect in patients with painful shoulder movements without injury

• arthritis - clinical patterns

• pain is on the lateral aspect of the shoulder and worse on abducting in the arc 60-90deg
• minimal pain when adducted
• pain is worse when washing hair or putting clothes out on clothes line
• aetiology:
  • subacromial impingement eg. unstable os acromiale or shape of acromion
  • repetitive overhead activities
  • direct trauma
  • crystal deposition
  • subacromial haemorrhage
  • infection, autoimmune
• Diagnosis is mainly clinical but can be supported by US although MRI is more useful and sensitive
• Rx:
  • conservative, rest, NSAIDs, physical therapy
  • for severe persistent cases, steroid injections may be considered
  • recalcitrant cases sometimes need surgery
• see also https://en.wikipedia.org/wiki/Subacromial_bursitis

• rotator cuff syndrome is usually caused by a tendinopathy which results from a combination of ageing with decreased local micro-vascular supply perhaps caused by prolonged shoulder adduction. The role of impingement with the anatomic variant shape of the acromion is another possible aetiologic factor.
• the impingement syndrome associated with rotator cuff injuries tends to cause pain with abduction ranging from 60-120° when the rotator cuff tendons are compressed against the anterior acromion and coracoacromial ligament.
• strength of the anterior cuff (subscapularis) can be assessed using the lift-off test, which is performed with the arm internally rotated behind the back and the hand then pushes against resistance posteriorly (ie. liftig hand away from the back).
• The posterior cuff (infraspinatus and teres minor) is isolated best in 90° of forward flexion with the elbow flexed to 90°, testing external rotation.
• Winging of the scapula as the patient pushes against the wall indicates serratus anterior weakness.
• supraspinatus strength can be tested with the elbow extended, the shoulder in full internal rotation, and the arm in the scapular plane (thumbs down position).

• rest, non-steroidal anti-inflammatory drugs (NSAIDs)
• sleep with pillow between trunk and arm to avoid prolonged adduction
• home exercise program
  • avoid adduction - ie do push ups, etc with arm at 45deg to the body
  • avoid thumbs down position when arm abducted
  • avoid lifting heavy weights overhead
  • avoid activities such as throwing a baseball that put a significant amount of stress on the tendons
  • start with shoulder shrugs, rowing, and push-ups
• +/- corticosteroid injection into the subacromial space for severe pain

• this is mainly due to weak or damaged structures which usually maintain shoulder joint enlocation
• see Stat Pearls: Shoulder Subluxation
• initial Mx is sling, analgesics, avoiding postures which contribute
• ongoing Mx is exercises to strengthen muscles, etc
• surgical Mx may be indicated for chronic subluxations in younger, active patients

• sudden paralyzing pain & weakness in the arm in young athletes with glenohumeral joint instability (ie. recurrent shoulder dislocations)
• transient radial pulse obliteration
• transient shoulder subluxation in elevation and external rotation
• 30% have co-existent thoracic outlet syndrome
• 2/3rds have a Bankart lesion
  • an injury of the anterior (inferior) glenoid labrum due to repeated (anterior) shoulder dislocation
  • a pocket then forms at the front of the glenoid which allows the humeral head to dislocate into it
  • see wikipedia
  • often accompanied by a Hill-Sachs lesion, which is damage to the posterior aspect of the humeral head.
• see Phong Tran's website

• see Emedicine - FSS

• mainly 40-70 year olds, women > men
• 3% lifetime risk
• main risk factor is a period of shoulder immobilization.

• may follow injury of surgery to the shoulder or upper limb or prolonged immobilisation
• may occur in conditions such as diabetes, thyroid disease, inflammatory diseases, etc
• may be due to certain medications such as flouroquinolone antibiotics, vaccination, antiretrovirals

• often an end stage of rotator cuff syndrome
• has a strong association with Dupuytren's contracture

• focal tenderness over the biceps tendon
• rest, non-steroidal anti-inflammatory drugs (NSAIDs), referral to physiotherapy
• rupture of one of the proximal heads of the biceps may occur following trivial injury in the elderly as a result of degenerative change, and this may have initial pain followed by relief once it ruptures then the characteristic “Popeye” bulge in the biceps muscle appears. Proximal ruptures may not require surgical repair unless it occurs in younger patients.
• rupture of biceps tendon

• bone tumours or cysts - pathologic fracture of bone cysts, metastatic tumours

• usually results from a fall onto the lateral aspect of the shoulder which forces the acromion under the distal clavicle straining or tearing the acromio-clavicular ligaments
• usually evidenced by swelling superiorly above the AC-joint
• A-C joint Xrays may demonstrate a widening of the joint
• initial ED Mx is broad arm sling and possible referral to orthopaedics

• Shoulder Dislocation (antero-inferior)
• posterior dislocation of the shoulder

• check for damage to the axillary nerve
• most are managed by collar and cuff with weight of the elbow used to gravitationally straighten any angulation
• many also apply a U-slab for “protection” and added gravitational weight
• patient should be advised to avoid putting weight on the elbow

• red flags: suggested by trauma with acute painful shoulder, normal XRay and inability to actively abduct greater than 90deg (this is particularly sensitive if pain is not the limiting factor)
• see acute rotator cuff tear
• if suspected, and pain not settling within 1-2 weeks:
  • arrange USS or MRI scan (sensitivity of 100% and specificity of 95%) within 1-2wks of injury and if present, early surgery within 1 month of injury appears to be preferable