Triceps Tendon (Full)

tendo musculi tricipitis brachii

The triceps tendon is the thickest tendon in the posterior arm, inserting broadly on the posterior olecranon. It is the least commonly ruptured large tendon in the body — triceps tendon rupture is very rare, occurring from direct impact (posterior fall with the elbow flexed) or steroid injection at the insertion. The patient is unable to extend the elbow against gravity. Surgical repair using non-absorbable suture through bone tunnels in the olecranon is mandatory for complete tears.

Region: Upper Arm

Biomechanics

Function & Actions

Elbow extension force transmission from the triceps to the olecranon — the only elbow extensor

Clinical Relevance

Clinical Notes

Triceps tendon rupture produces a palpable posterior elbow gap and inability to extend against gravity. The Thompson test (squeezing the posterior arm does not produce elbow extension) confirms complete rupture analogously to Thompson's Achilles test. MRI confirms the diagnosis and guides repair planning. Triceps avulsion requires emergency surgical repair to maintain elbow extension function.

Pathology

Common Injuries & Conditions

Triceps Tendon Rupture

Rare posterior elbow tendon avulsion producing extension weakness — surgical repair through olecranon bone tunnels restores function.