Ulna - Ulna


The ulna is the caudolateral bone of forearm, divide into three segments:

  • Proximal extremity with the olecranon
  • Body (shaft) of ulna
  • Distal extremity with the head of ulna.

The development of ulna varies considerably between species due to the evolution of rotation movement in forearm:

  • In human, the ulna is well developped due to an important rotational movement (pronation and suppination).
  • In carnivores, the movement is quite limite but the radius and ulna remains separate.
  • In the pigs, the rotation is prevented by firm soft tissue bridging the interosseous space.
  • In horses and ox, there is no movement and the two bones are fused.


Text by Antoine Micheau, MD - Copyright IMAIOS


Download vet-Anatomy

Mobile and tablet users, you can download on Appstore or GooglePlay.

vet-Anatomy on Appstore vet-Anatomy on Googleplay