Radial collateral ligament of wrist joint
Ligamentum collaterale radiale carpi
A short band on the thumb side of the wrist joint, passing from the radial styloid process down to the scaphoid.
At a glance
- English
- Radial collateral ligament of wrist joint
- Latin (TA2)
- Ligamentum collaterale radiale carpi
- System
- Ligament
- Region
- Hand
- Side
- Paired, left and right
About the radial collateral ligament of wrist joint
The radial collateral ligament reinforces the lateral, or thumb, side of the radiocarpal joint. It is a short band that leaves the tip of the radial styloid process and descends to the scaphoid, fixing to its lateral surface close to the margin of the bone's upper articular surface. A few of its fibres carry on to the outer face of the trapezium.
Its most important relation is the radial artery. After leaving the front of the forearm, the artery curves round the lateral side of the wrist across the floor of the anatomical snuffbox and lies directly on this ligament and the scaphoid. Above it run the extensor pollicis brevis and abductor pollicis longus tendons, so the artery sits sandwiched between those tendons and the ligament.
The ligament's task is to check the hand when it swings towards the little-finger side. In ulnar deviation the radial styloid moves away from the scaphoid and the band tightens, setting a limit to the movement. Many anatomists treat it less as a discrete collateral ligament than as a thickened part of the capsule, because the radial side of the wrist is also braced by the strong palmar radiocarpal ligaments and by the tendons that cross it.
A fall on the outstretched hand can sprain this band, but tenderness in the snuffbox after such a fall must first raise suspicion of a scaphoid fracture, which is easy to miss on early X-rays. When surgeons remove part of the radial styloid, they take care not to take so much bone that the ligaments arising nearby lose their anchorage.
Attachments and function
- Attaches from
- The apex of the radial styloid process.
- Attaches to
- The lateral side of the scaphoid next to its proximal articular surface, with some fibres reaching the trapezium.
- Function
- Limits ulnar deviation of the hand and strengthens the lateral part of the radiocarpal capsule.
- Nerve supply
- Articular twigs from the radial nerve and its posterior interosseous branch supply the lateral wrist capsule.
- Blood supply
- Small branches of the radial artery, which lies directly on the ligament.
Anthromica
See the radial collateral ligament of wrist joint 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.
