luxations

Luxation, or dislocation, is the displacement of a bone from its joint, resulting in loss of contact between the articular surfaces. It is distinct from a subluxation, in which contact is only partially lost. Luxations are typically traumatic but can be congenital or occur with joint laxity or connective tissue disorders.

Common sites include the shoulder (glenohumeral dislocation), elbow, hip, patella, temporomandibular joint, and finger joints. Causes include acute trauma from falls or accidents, sports injuries, and high-energy impacts. Predisposing factors include joint hypermobility, previous dislocations, aging, neuromuscular disorders, and connective tissue diseases.

Patients usually present with severe pain, deformity, swelling, and marked limitation of movement. Neurovascular status should be assessed distal to the injury because dislocations can compromise nerves or blood vessels.

Diagnosis is based on clinical examination and imaging. Plain radiographs are routine; CT can assess complex fractures or occult injuries, and MRI may reveal associated soft tissue injuries such as labral tears or ligament ruptures.

Management often requires urgent reduction to relieve pain, restore alignment, and reduce complications. Analgesia or sedation is used; many joints can be reduced by closed techniques, followed by immobilization. Open reduction or surgery is indicated for irreducible dislocations, fracture-dislocations, nerve or vessel injury, or intra-articular fragments. Specific joints, such as the hip, require prompt reduction to minimize avascular necrosis risk.

Complications include recurrent dislocations, cartilage or bone damage, chronic instability, nerve or vascular injury, and avascular necrosis (notably of the hip). Prognosis varies by joint, but early, appropriate treatment improves outcomes. Prevention focuses on injury avoidance, strength and proprioception training, and, where applicable, bracing or immobilization after a dislocation.