Posterior Elbow Capsule Ligament

capsula articularis cubiti posterior

The posterior elbow capsule is a thin, relatively lax fibrous structure covering the olecranon fossa and the posterior aspects of the radiohumeral and ulnohumeral joints. It attaches proximally along the olecranon fossa margins and distally to the olecranon and radial neck. Its laxity in flexion allows the olecranon to fit into the fossa in full extension.

Region: Upper Arm

Biomechanics

Function & Actions

Provides posterior containment of the elbow joint and limits hyperextension. The posterior capsule becomes taut in full extension, restraining further range of motion.

Clinical Relevance

Clinical Notes

The posterior capsule is contracted in post-traumatic elbow stiffness, producing a flexion contracture that limits terminal extension. Posterior capsulotomy or capsulectomy is the primary procedure for addressing extension loss in elbow stiffness. The posterior capsule is torn in elbow dislocations and must be repaired as part of ligamentous reconstruction. Heterotopic ossification in the posterior capsule is a common cause of elbow stiffness after distal humeral fractures.

Pathology

Common Injuries & Conditions

Posterior Elbow Capsule Contracture

Fibrotic thickening of the posterior elbow capsule after trauma or prolonged immobilisation producing a fixed flexion contracture, treated by progressive stretching or surgical posterior capsulotomy.