Capitohamate interosseous ligament
Ligamentum capitohamatum interosseum
A short, strong ligament deep in the distal row of the carpus, binding the capitate to the hamate across their facing surfaces.
At a glance
- English
- Capitohamate interosseous ligament
- Latin (TA2)
- Ligamentum capitohamatum interosseum
- System
- Ligament
- Region
- Hand
- Side
- Paired, left and right
About the capitohamate interosseous ligament
The capitohamate interosseous ligament lies between the capitate and the hamate, the two largest bones of the distal row of the carpus. The capitate is the central bone of the wrist and the hamate lies on its ulnar side. Their facing surfaces are partly covered by cartilage, where they form a small intercarpal joint, and partly rough; the ligament fills the space between the rough areas, mainly towards the distal part of the joint.
Its fibres are short and dense and pass straight across from the ulnar side of the capitate to the radial side of the hamate. The ligament does not completely close the joint, so the midcarpal joint space communicates around it. It is reinforced on the surface by the dorsal and palmar capitohamate bands, which belong to the dorsal and palmar intercarpal ligaments.
Together with the interosseous ligaments between the trapezium, trapezoid and capitate, it binds the four bones of the distal row into an almost rigid unit. This unit moves as one with the bases of the metacarpals, especially the second and third, which are themselves firmly fixed. The distal row therefore acts as a stable platform for the hand, while the proximal row provides most of the adaptive movement at the wrist. The ligament also supports the carpal arch, which forms the floor of the carpal tunnel.
Because the distal row is so firmly bound, isolated tears of this ligament are uncommon. It may be disrupted in high-energy injuries that split the carpus lengthways between the capitate and hamate. Recognising such an injury is important because the hand then loses its stable platform.
Attachments and function
- Attaches from
- The rough, non-articular ulnar surface of the capitate.
- Attaches to
- The rough, non-articular radial surface of the hamate.
- Function
- Binds the capitate to the hamate, making the distal carpal row act as one rigid unit and supporting the carpal arch.
Anthromica
See the capitohamate 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.
