(iv) Elbow instability

Acute elbow instability ranges from simple dislocations without significant fractures to complex dislocations involving fractures of the coronoid and radial head (“terrible triad”). Simple dislocations for the most part are stable after reduction, managed with early mobilisation and have good outcomes with relatively low complication rates. In contrast, complex fracture-dislocations render the elbow very unstable and therefore surgical intervention is usually necessary to restore bony and ligamentous stability to allow early range of motion. The risk of complications, including stiffness, chronic instability, heterotopic ossification and arthrosis, are high and clinical outcomes have traditionally been suboptimal. Detailed knowledge of the relevant anatomy is crucial in the understanding of injury patterns and in the application of successful systematic treatment algorithms that will minimise complications and improve outcomes.Chronic instability is most commonly posterolateral due to incompetence of the lateral ulnar collateral ligament (LUCL). Patients present with episodes of recurrent subluxation or dislocation. Most symptomatic patients require surgical reconstruction of the LUCL (using tendon autografts or allografts) which produces favourable clinical results.