Posterior shoulder dislocation
Background
- Via forceful internal rotation/adduction (sz, electric shock) or blow to ant shoulder
- Neurovascular and rotator cuff tears are less common than in ant dislocations
Clinical Features
- Prominence of posterior shoulder and ant flattening of normal shoulder contour
- Pt unable to rotate or abduct affected arm
Diagnosis
- Plain film X-ray
- Scapular "Y" view shows humeral head in posterior position
Differential Diagnosis
Shoulder and Upper Arm Diagnoses
Traumatic/Acute:
- Shoulder Dislocation
- Clavicle fracture
- Humerus fracture
- Scapula fracture
- Acromioclavicular joint injury
- Glenohumeral instability
- Rotator cuff tear
- Biceps tendon rupture
- Triceps tendon rupture
- Septic joint
Nontraumatic/Chronic:
- Rotator cuff tear
- Impingement syndrome
- Calcific tendinitis
- Adhesive capsulitis
- Biceps tendinitis
- Subacromial bursitis
- Cervical radiculopathy
Refered pain & non-orthopedic causes:
- Referred pain from
- Neck
- Diaphragm (e.g. gallbladder disease)
- Brachial plexus injury
- Axillary artery thrombosis
- Thoracic outlet syndrome
- Subclavian steal syndrome
- Pancoast tumor
- Myocardial infarction
- Pneumonia
- Pulmonary embolism
Management
- Reduce
- Traction applied to adducted arm in long axis of humerus
- Assistant pushes humeral head anteriorly into glenoid fossa
- Sling and swath
Disposition
- Discharge after reduction
- Ortho follow-up