It is the medial bone of the forearm. It articulates proximally with the humerus and radius and distally only with the radius. It is a long bone that has two epiphyses and a diaphysis.

Proximal Epiphysis

  • Olecranon – Large eminence that forms the tip of the elbow
  • Trochlear Notch – Large depression formed by the olecranon and coronoid process and serves for articulation with the trochlea of the humerus
  • Coronoid Process – Projects from the anterior and proximal part of the body of the ulna
  • Radial Notch – Articulates with the radial head
  • Ulnar tuberosity

Distal Epiphysis

  • Head of Ulna – Rounded articular eminence located laterally
  • Styloid Process – Located more medially and is more salient (non-articular)


It has three edges and three faces.


  • Interosseous Edge
  • Front Edge
  • Dorsal Edge


  • Front Face
  • Dorsal Face
  • Medial Face

The Ulna articulates with two bones: the Humerus and the Radius.

Articulações Proximais da Ulna Articulação Distal da Ulna

 Ulna - Vistas Anterior, Posterior e Lateral
Source: SOBOTTA, Johannes. Atlas of Human Anatomy. 21 ed. Rio de Janeiro: Guanabara Koogan, 2000.

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