Ulna

The elbow bone ( ulna ) is located on the medial side of the forearm ( ulnar direction ). On the proximal part, there is an articular surface, forming a fossa of the medial ulnar and proximal radioulnar joints. The body of the bone ( corpus ulnae ) has a triangular cross-section. The distal end of the ulna ( caput ulnae ) is indirectly articulated with the carpus and directly with the radius .

Anatomy

Proximal part

• It creates a notch, incisura trochlearis , in the anatomical position it is open ventrally, into which the trochlea humeri fits , and is bordered by the following formations:
  • olecranon – the most proximal part of the bone, when the joint is flexed it forms the tip of the elbow;
  • processus coronoideus – distal border of the notch;
  • incisura radialis – a small depression covered by cartilage, connected to the articular surface, into which the caput radii fits .

The body of the ulna

• The body has a triangular cross-section , the edges are reversed ventrally, dorsally and laterally ( margo anterior, posterior et interosseus ).
• Margo interosseus faces the radius and is connected to it by an interosseous ligamentous membrane.
• The foramen nutricum is directed proximally.

The head of the ulna

• The head of the ulna is formed by the cylindrical articular surface of the circumferential articularis , which laterally attaches to the radius and proximally to the discus articularis .
• From the mediodorsal side, the processus styloideus ulnae emerges , which is easily palpable.

Clinical contexts

See Forearm Fractures for more detailed information .

Bones of the left forearm - ventral view.

Bones of the left forearm - dorsal view.

Links

Related articles

• Upper limb bones
• Upper limb muscles

External links

• Ulna (česká wikipedie)
• Ulna (anglická wikipedie)

References

• CIHÁK, Radomír. Anatomy. 2nd edition. Prague: Grada Publishing, as, 2008. p. 516.  ISBN 80-7169-970-5 .