Palmar capitohamate ligament
Ligamentum capitohamatum palmare
A short, strong band on the palm side of the wrist that ties the capitate to the hamate in the distal carpal row.
At a glance
- English
- Palmar capitohamate ligament
- Latin (TA2)
- Ligamentum capitohamatum palmare
- System
- Ligament
- Region
- Hand
- Side
- Paired, left and right
About the palmar capitohamate ligament
The palmar capitohamate ligament is an intrinsic ligament of the carpus, which means that both of its ends are fixed to carpal bones rather than to the radius, ulna or metacarpals. It crosses the front of the joint between the capitate, the largest carpal bone, and the hamate, which lies on its ulnar side. Its fibres run roughly across the wrist, from the palmar surface of one bone to the palmar surface of the other.
The four bones of the distal row are bound so firmly by palmar, dorsal and interosseous ligaments that they move almost as one piece, and they are also locked to the bases of the metacarpals. The capitate and hamate are tightly joined. Besides this palmar band, a stout interosseous ligament lies deep between them and a dorsal capitohamate ligament covers the back of the joint. On the palmar side the ligament lies in the floor of the carpal tunnel, deep to the long flexor tendons.
By holding capitate and hamate together, the ligament helps make the distal row a stable base for the central and ulnar metacarpals, so that load passing along the hand is shared across the wrist. Movement of the wrist therefore takes place mainly at the radiocarpal and midcarpal joints, not between these two bones. Injury to the ligament alone is uncommon. It is usually torn only in high-energy crushing injuries that split the carpus lengthwise, the rare axial carpal dislocations.
Attachments and function
- Attaches from
- Palmar surface of the capitate.
- Attaches to
- Palmar surface of the adjacent hamate.
- Function
- Binds capitate and hamate together on the palmar side, so that the distal carpal row moves as a single unit.
- 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 palmar capitohamate 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.
