Lunotriquetral interosseous ligament
Ligamentum lunotriquetrum interosseum
A C-shaped ligament joining the lunate and triquetrum in the proximal row of the carpus, sealing the gap between them.
At a glance
- English
- Lunotriquetral interosseous ligament
- Latin (TA2)
- Ligamentum lunotriquetrum interosseum
- System
- Ligament
- Region
- Hand
- Side
- Paired, left and right
About the lunotriquetral interosseous ligament
The lunotriquetral interosseous ligament binds the lunate to the triquetrum, its neighbour on the ulnar side of the proximal carpal row. It runs around the edges of the joint between the two bones and, seen from the side, is C-shaped, covering the dorsal, proximal and palmar margins of the joint and leaving the distal side open to the midcarpal joint.
Three parts are described. The palmar part is the thickest and strongest. The dorsal part is thinner. Between them, along the proximal edge, lies a membranous part made of fibrocartilage; it carries little load and faces the radiocarpal joint, which it separates from the midcarpal joint. This pattern is the reverse of the scapholunate ligament on the other side of the lunate, where the dorsal part is the strongest.
The ligament ties the triquetrum to the lunate so that they move together. The proximal row has no tendons attached to it and is held in balance between two tendencies: the scaphoid tends to pull the lunate into flexion, and the triquetrum tends to pull it into extension. Through this ligament the triquetrum keeps its hold on the lunate. It also passes load across the ulnar side of the wrist.
Tears of the lunotriquetral ligament cause pain on the ulnar side of the wrist, often after a fall on the outstretched hand or from wear related to a long ulna. If the ligament and the dorsal supports are both lost, the lunate follows the scaphoid into flexion, a pattern of carpal instability recognised on lateral X-rays. The ligament is often assessed alongside the triangular fibrocartilage complex, which lies just proximal to it.
Attachments and function
- Attaches from
- The margins of the ulnar articular surface of the lunate.
- Attaches to
- The margins of the radial articular surface of the triquetrum.
- Function
- Binds the lunate and triquetrum so that they move together, keeps the triquetrum's extending pull on the lunate and seals the radiocarpal from the midcarpal joint.
Anthromica
See the lunotriquetral interosseous 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.
