Characteristics

• Usually secondary to a fall on an outstretched hand or a direct blow.

• Less commonly caused by triceps contraction with a flexed elbow.

• Extra-articular avulsion fractures less common than intra-articular ‘true’ olecranon fractures.

• Undisplaced fractures are defined (Colton) as having < 2 mm displacement, active flexion to 90° and active extension.

Clinical features

• Localised pain, bruising crepitus over the olecranon.

• A palpable separation may be felt.

• Inability to extend the elbow against gravity indicates complete disruption of the extensor mechanism.

• Assess ulna and anterior interosseous nerve function as injury can occur at the time of trauma and in treatment with ORIF.

Radiological features

• AP and true lateral flexed elbow. Displacement best evaluated on the lateral.

• Again be aware of epiphyseal appearances. A bifid epiphysis is normal although fusion should occur by 14 years. Rounded calcification within the triceps tendon can also be misleading.

• Important to assess the size of the proximal fragment – may require excision – and the degree of fragmentation – which may determine treatment modality.

Management

• Assess soft tissues, neurovascular status and immobilisation initially with above elbow backslab.

• Undisplaced – immobilise in approximately 90° of flexion. Reassess that no displacement at 1 week and mobilise around 4 weeks.

• Non-operative treatment can also be applied to displaced fractures in the elderly, low-demand, high surgical-risk patient – here the aim of treatment is pain-free fibrous union or even pseudarthrosis and therefore mobilisation should be as early as possible to prevent joint stiffness.

• Displaced – requires ORIF with k-wires and tension band or reconstruction plate for the multi-fragmentary fracture. Early mobilisation if possible.

• Avulsion fractures – if the proximal fragment is small, excision and reattachment of the triceps with suture anchors allows early mobilisation, maintains reasonable joint congruence and stability.