Oblique cord
Chorda obliqua
A small flat ligament in the upper forearm, passing from the ulnar tuberosity down and outwards to the radius just below its tuberosity.
At a glance
- English
- Oblique cord
- Latin (TA2)
- Chorda obliqua
- System
- Joint
- Region
- Upper limb
- Side
- Paired, left and right
About the oblique cord
The oblique cord is a slender band that ties the radius and ulna together near the elbow, in the gap above the interosseous membrane. It starts at the outer edge of the ulnar tuberosity, low on the coronoid process, and runs downwards and laterally to attach to the radius a short way below the radial tuberosity. It has collected many names over the years, among them the oblique ligament, the chorda obliqua and the ligament of Weitbrecht.
Its fibres slope the other way from most of those in the interosseous membrane, which pass downwards and medially from radius to ulna. In adults it measures a few centimetres in length and usually narrows from its ulnar end to its radial end. In form it ranges between a round strand and a thin flat sheet, and it is absent in a considerable proportion of people. Between it and the upper border of the interosseous membrane is a gap through which the posterior interosseous vessels pass to the back of the forearm.
The function of the cord is uncertain. Suggestions have included strengthening the interosseous membrane near the elbow, restraining rotation of the forearm and protecting the radius against bending. Studies of human and other primate forearms, however, have found that it does not limit supination and seems to add little to the steadiness of the upper forearm. It may act as an extra tie between the two bones, supporting the annular ligament and the interosseous membrane, and it may resist forward shearing of the upper radius under heavy loads.
Some regard it as a remnant from ancestors whose forelimbs bore weight. Clinically it is of little importance; it can be divided without any obvious loss of function.
Attachments and function
- Formed by
- Outer edge of the ulnar tuberosity, near the foot of the coronoid process.
- Joins
- Shaft of the radius just below the radial tuberosity.
- Movements
- Acts as an accessory tie between radius and ulna near the elbow; its exact role is uncertain and it does not appear to limit supination.
Anthromica
See the oblique cord 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.
