Fracture de la clavicule

The clavicle, proximal humerus and the scapula together form the shoulder joint. The clavicle also forms the bony connection between the upper limb and the thorax. It articulates with the acromion process of the scapula laterally, at the acromioclavicular joint, and the manubrium of the sternum medially, at the sternoclavicular joint. Ligaments connect the coracoid process of the scapula to the mid-clavicle. The clavicle protects the brachial plexus, major underlying vessels and the lung apex.

How common are clavicle fractures? (Epidemiology)¹

• This is one of the most common acute shoulder injuries.

• It accounts for 2.6% to 4% of all fractures.

• 80% of clavicle fractures are located in the middle third of the clavicle.

• It is more common in children. It is the most common of all paediatric fractures.

Mécanisme de la lésion

• It is usually caused by a fall on to the lateral shoulder.

• Less commonly, it occurs after a direct blow to the clavicle or by falling on an outstretched arm.

• It is a common injury in contact sports, cycling and winter sports.

• In the neonate:
  

  • Complication of breech delivery.

  • One recognised third-line management of shoulder dystocia is surgical division of the clavicle (cleidotomy).²

Clavicle fracture symptoms

• History of a fall or trauma.

• Pain, swelling and tenderness around the clavicle.

• There may be obvious deformity, including tenting of the skin and bruising.

• There may be non-use of the arm on the affected side in neonates.

Examen

Firstly, assess 'Airway, Breathing, Circulation' (ABC) and manage as necessary.

• Diagnosis of a fractured clavicle can usually be made clinically, as the clavicle is superficial and easily palpable. Examine the clavicle from behind the patient.

• Auscultate and percuss the lung fields to exclude a complicating pneumothorax.

• Perform a neurovascular examination of the upper limb on the affected side - examine the upper limb pulses; look for evidence of decreased perfusion, including changes in skin colour; assess sensation and muscle power.

• Assess and examine for any other injuries.

Enquêtes

• Anteroposterior view X-ray of the clavicle detects most fractures.

• Non-displaced fractures may be better seen on a 20° or 45° cephalic tilt view.

• Ensure that there is no co-existing scapular fracture which would mean a 'floating shoulder'.

• Sternoclavicular or acromioclavicular joint disruption may require CT/MRI scanning to characterise fully.

• CXR if pneumothorax is suspected.

• Angiography if vascular damage is suspected.

Types of clavicle fracture (fracture classification)

Allman classification:³

• Group 1: middle one third of the clavicle (the shaft). Most common (approximately 80%) in both adults and children.⁴ If displaced, the lateral fragment is usually pulled down by weight of limb and the medial fragment tends to be displaced upwards by the action of the sternocleidomastoid muscle.

• Group 2: lateral one third of the clavicle (the acromial end). 10-15% of clavicle fractures.⁴ Subdivided into:
  

  • Type I - non-displaced/minimal displacement; intact ligaments hold the fragments together.

  • Type II - displaced; the coracoclavicular ligament ruptures and the medial segment of the fractured clavicle displaces upwards.

  • Type III - articular surface fractures (involving the acromioclavicular joint).

• Group 3: medial one third of the clavicle (the sternal end). 5% of clavicle fractures.⁴ If displaced, these have a higher rate of significant intrathoracic or neurovascular injury.

Clavicle fracture treatment and management

In a GP setting

• Assess ABC, perform a full examination and examine for any other injury, as described above.

• Immobilise in a sling the arm on the affected side.

• Refer to secondary care for X-ray investigation.

After confirmed X-ray diagnosis

• Although treatment of these fractures is usually non-surgical, displaced clavicle fractures may be considered for surgical treatment because of their greater risk of non-union.¹

• Open fractures obviously need orthopaedic referral.

• Management then depends on the fracture classification:
  

  • Group 1: most are treated conservatively, whether displaced or non-displaced, with immobilisation using a sling, figure-of-eight bandage, and straps or splints. A Cochrane review concluded that further research is warranted to determine which method of conservative management is appropriate.⁵

  • There is no conclusive evidence to establish whether conservative or surgical management should be preferred. Therefore treatment options must be chosen on an individual patient basis, after careful consideration of the relative benefits and harms of each intervention and of patient preferences.¹

  • Group 2: type I and type III fractures can be treated with immobilisation. Type II fractures may require surgery. The method of surgical treatment for clavicular fractures is controversial. Intramedullary screws or nails and plate fixation of the clavicle are the most usual surgical options.

  • Group 3: if non-displaced, immobilisation is all that is needed. Displaced fractures may require surgery.

• Analgesia such as paracetamol or, if the pain is severe, opiates, should be prescribed.

• Orthopaedic outpatient follow-up is usually arranged.

• Mobilisation exercises/physiotherapy should be provided.

The method of surgical treatment for clavicular fractures is controversial. Intramedullary screws or nails and plate fixation of the clavicle are the most usual surgical options. A very recent development is the use of an arthroscopic procedure to stabilise clavicular fractures, using a 'tightrope'.

Complications of clavicle fracture

Complications are uncommon.

Aiguë

• Pneumothorax.

• Hémothorax.

• Brachial plexus injury.

• Blood vessel injury (including subclavian vessels, internal jugular vein and axillary artery).

En retard

• Non-union and malunion (no radiographic healing at 4-6 months). The rate of non-union was 7% in one series.⁶ In another, it was 6.2%.⁷ Both studies were undertaken on groups receiving non-operative treatment.

• Deformity due to excessive callus formation during fracture healing.

• Syndrome du défilé thoracique.

• Brachial plexus compression due to callus formation.

• Arthritis (more common in fractures involving the articular surface - group 2, type III).

Pronostic

• If managed promptly and correctly, this is excellent.

• Healing normally takes 6-8 weeks in an adult and 3-4 weeks in a child.

• One study showed that asymptomatic non-union does not appear to affect the functional outcome adversely in the medium term.⁸