Joints and ligaments · Upper limb
Palmar wrist ligaments !
The palmar radiocarpal ligaments run on the palm side of the wrist; they are the main restraints that keep the wrist bones from sliding off the radius.
Official name: Palmar radiocarpal ligaments
Opens in the Durgical app, no sign-up needed.
What it is
Strong bands on the palm side of the wrist from the radius to the carpal bones.
What it does
The main restraints that keep the wrist bones from sliding off the radius.
Key facts
- Attaches
- Palmar distal radius to scaphoid, capitate and lunate (radioscaphocapitate, long and short radiolunate)
- Function
- Main restraint keeping the carpus on the radius
- Tight in
- Wrist extension
Relations
- In front
- Floor of the carpal tunnel: FPL tendon and FDP tendons, with the median nerve above them; the FCR tendon crosses on the radial side in its own channel
- Behind
- Scaphoid and lunate, and the joint surface of the distal radius
- Lateral
- Radial styloid, where the radioscaphocapitate ligament arises; the radial artery winds around the styloid towards the anatomical snuffbox
- Medial
- Ulnocarpal ligaments; the ulnocapitate ligament and the radioscaphocapitate ligament converge on the capitate as a V
How to find it
Not palpable. In the palmar (FCR) approach to the distal radius they lie deep to the pronator quadratus area, arising from the palmar rim just beyond the watershed line; at arthroscopy they are seen through the dorsal 3–4 portal.
On imaging
PA view: in ulnar translocation the lunate overhangs the ulnar edge of the radius by more than about half its width and the gap between radial styloid and scaphoid widens. MRI shows the ligaments as striated low-signal bands; arthroscopy shows them directly.
Clinical notes
- Palmar plates for distal radius fractures are kept proximal to the watershed line, where these ligaments arise; a plate sitting too far distally can rub on and rupture the FPL tendon
- Radial styloid (chauffeur's) fractures carry the origin of the radioscaphocapitate ligament and may be part of a carpal ligament injury
- When these ligaments fail (trauma, rheumatoid arthritis) the carpus can slide ulnarly off the radius: ulnar translocation
Test yourself
Think of the answer, then tap the question to see it.
What are the palmar wrist ligaments, from radial to ulnar?
Radioscaphocapitate, long radiolunate, radioscapholunate (ligament of Testut) and short radiolunate.
What is the space of Poirier?
A weak area over the capitolunate joint between the radioscaphocapitate and long radiolunate ligaments, through which the lunate escapes in perilunate dislocation.
What happens when the palmar wrist ligaments fail, as in rheumatoid arthritis?
Ulnar translocation: the carpus slides ulnarly off the radius, since these ligaments are its main restraint.
Why are palmar plates for distal radius fractures kept proximal to the watershed line?
The palmar wrist ligaments arise there; a plate placed too distally can rub on and rupture the flexor pollicis longus tendon.
Educational information, not medical advice. For any symptom, see a health professional.
Its names
- Official Latin (TA2)
- ligamentum radiocarpeum palmare TA2 1788
- Official Spanish (DeCS)
- Ligamento radiocarpiano palmar
- English (TA2)
- Palmar radiocarpal ligaments
- Also called
- volar radiocarpal ligaments
Related
Sources: Terminologia Anatomica (TA2); Anatomy, Shoulder and Upper Limb, Hand Radiocarpal Joint; Anatomy, Shoulder and Upper Limb, Wrist Joint.
Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake
Representative model, for educational purposes only.
