Triquetrohamate ligament
Ligamentum triquetrohamatum
A palmar ligament on the ulnar side of the wrist that binds the triquetrum to the hamate across the midcarpal joint.
At a glance
- English
- Triquetrohamate ligament
- Latin (TA2)
- Ligamentum triquetrohamatum
- System
- Ligament
- Region
- Hand
- Side
- Paired, left and right
About the triquetrohamate ligament
The triquetrohamate ligament crosses the ulnar part of the midcarpal joint on its palmar side. It runs from the palmar surface of the triquetrum distally to the palmar surface of the body of the hamate. It lies on the ulnar side of the triquetrocapitate ligament, and the two together form the ulnar arm of the palmar arcuate ligament, whose radial arm is the radiocapitate ligament.
The joint it crosses has an unusual shape. The hamate offers the triquetrum a spiral facet, so that as the wrist moves between radial and ulnar deviation the triquetrum slides along this slope and its height on the hamate changes. This screw-like contact helps steer the proximal row from flexion into extension. The triquetrohamate ligament, together with the dorsal ligaments of the region, controls this gliding and keeps the triquetrum in contact with the hamate.
Laxity or tearing of the ulnar arm of the arcuate ligament allows the proximal row to lag in flexion and then snap into extension during ulnar deviation, producing a painful, sometimes visible clunk on the ulnar side of the wrist, known as palmar midcarpal instability. Injury to the ligament may also follow a fall onto the hand and is one of the causes of pain on the ulnar side of the wrist, along with injuries of the triangular fibrocartilage complex and the lunotriquetral ligament.
Attachments and function
- Attaches from
- Palmar surface of the triquetrum.
- Attaches to
- Palmar surface of the body of the hamate.
- Function
- Binds the triquetrum to the hamate on the palmar side and controls the gliding of the triquetrum on the hamate during ulnar and radial deviation.
- Nerve supply
- Articular twigs from the anterior interosseous nerve and the deep branch of the ulnar nerve, which supply the palmar side of the carpus.
- Blood supply
- Small branches of the palmar carpal arch, reinforced by recurrent branches from the deep palmar arch.
Anthromica
See the triquetrohamate ligament where it really sits, with every layer of the body around it.
- Every layer, one body. Peel from muscle to bone, nerve, vessel and organ, and turn it any way.
- English and Latin. Every structure named the way your exam names it.
- Quiz until it sticks. Short drills on the structures you keep missing.
Free to start. No card.
