- The shoulder girdle consists of the clavicle, scapula and humerus
Midshaft Clavicle Fracture
Epidemiology
- Young, active males
- >70% of clavicle fractures occur in the middle segment
Etiology
- Mechanism of injury – fall on an outstretched arm or direct trauma to shoulder
- Associated conditions – ipsilateral scapular fracture, rib fracture, pneumothorax, neurovascular injury
Pathophysiology
- Middle third is the thinnest part of the clavicle and is the only area that is not reinforced with muscle and ligaments – makes it more vulnerable to fracture
- Displaced fractures
- Medial fragment – SCM muscle pulls the medial fragment postero-superiorly
- Lateral fragment – pectoralis major muscle pulls the lateral fragment infero-medially
- Open fracture – is as a result of the medial fragment ‘button-holing’ through the platysma
Classification
- AO classification
- Types – A (simple); B (wedge); C (complex)
- Neer classification
Clinical features
- Anterior shoulder pain
- Skin tenting – indicates impending open fracture
Diagnosis
- X-ray – to determine displacement
- CT – to evaluate vascular injury
Treatment
- Sling with gentle ROM exercises – for <1cm displacement and no neurovascular injury
- ORIF – severe displacement; neurovascular injury
Distal Clavicle Fracture
Epidemiology
- More common in older/osteoporotic patients
- Less common than midshaft clavicle fractures
Etiology
- Mechanism – direct compressive force to the shoulder (fall/trauma)
- Associated conditions – floating shoulder, rib fracture, pneumothorax, neurovascular injury
Anatomy of acromioclavicular joint
- Acromioclavicular ligament – horizontal stability
- Coracoclavicular ligament – vertical stability
- 2 components – trapezoid ligament, conoid ligament
Pathophysiology
- Displacement is based on
- Fracture location – extra-articular vs intra-articular
- Fracture pattern – simple vs Comminuted fracture
- Integrity of coracoclavicular ligaments (CCL)
Classification
- AO classification
- Types – A (non displaced + intact CCL); B (displaced + intact CCL); C (displaced + torn CCL)
- Neer classification
Clinical features
- Anterior shoulder pain, swelling, tenderness to palpation
- AC joint deformity
- Tenting of skin indicates impending open fracture
- Weakness of external rotation when arm is adducted – indicates suprascapular nerve injury
Diagnosis
- X-ray – to determine displacement
- CT
Treatment
- Sling with gentle ROM exercises
- Operative – ORIF
Scapular Fracture
Epidemiology
- Uncommon fracture
- 50% involve body and spine of scapula
Etiology
- Due to high energy trauma, usually during chest trauma – e.g. in motor vehicle accidents
- Associated injuries – rib fractures, clavicle fracture, pulmonary injury, pneumothorax, head injury
Classification – based on location of fracture
- Coracoid fracture
- Acromial fracture
- Glenoid fracture
- Scapular neck fracture
- Scapular body fracture
Clinical features
- Localised pain, tenderness, swelling
- Reduced ROM
Diagnosis
- X-ray
- CT
Treatment
- Sling and ROM exercises – most fractures heal without further problems
- ORIF – for glenohumeral instability, displaced scapula neck, open fracture, loss of rotator cuff function
Sterno-clavicular Joint Dislocation
Epidemiology/etiology
- Traumatic causes – motor vehicle accidents
- Spontaneous – more common in young men
- Associated injuries
- Anterior dislocation – pneumothorax, hemothorax, rib fracture
- Posterior dislocation – subclavian vasculature injury, pneumothorax, oesophageal injury
Pathology
- Anterior dislocation – more common, less serious
- Posterior dislocation – more serious due to potential damage to mediastinal structure
Clinical features
- Anterior dislocation – palpable deformity
- Posterior dislocation – more subtle
- Dyspnea, stridor, dysphagia – if there is compression of thoracic structures
Diagnosis
- X-ray – joint space widening, displacement of medial head of clavicle
- CT – associated injuries to the mediastinum
Treatment
- Conservative treatment – for anterior dislocation
- Closed reduction
- ORIF – for unreduced posterior dislocations
Acromio-clavicular Joint Dislocation
- Rare injury
- Due to fall on the outer prominence of the shoulder
- Can result in partial or complete rupture of the acromio-clavicular or coracoclavicular ligaments
- Clinical features – localised pain and swelling
- Diagnosis – X-ray
- Treatment – sling and analgesia; ORIF