Distal radioulnar joint

Study entry

Classification

Pivot (trochoid) synovial joint.

Surfaces

Head of the ulna with the ulnar notch of the radius.

Capsule

Capsule deficient above; the synovial membrane forms the sacciform recess. The triangular articular disc ("triangular ligament" in clinical practice), from the margin of the ulnar notch of the radius to the base of the styloid process of the ulna, is the main stabilizer and separates this cavity from the radiocarpal one. Weak anterior and posterior ligaments reinforce the capsule.

Movements

In pronation the distal end of the radius rotates forward and inward, crossing the ulna; in supination it becomes parallel to it again.

Blood supply

Mainly the palmar and dorsal branches of the anterior interosseous artery, which form a network around the joint, with help from the posterior interosseous, branches of the ulnar and the carpal arches

Innervation

Anterior and posterior interosseous nerves.

Clinical

The muscles are the same as for the proximal radioulnar joint: the two work together in pronation and supination.

Source: cap. 3, «Articulaciones del miembro superior: articulación radioulnar distal»

Other structures in this region

• Radioulnar syndesmosis (interosseous membrane of the forearm)
• Superior and inferior transverse scapular ligaments
• Sternoclavicular joint
• Acromioclavicular joint
• Shoulder (glenohumeral) joint
• Elbow joint
• Proximal radioulnar joint
• Radiocarpal joint