Name

Ulna

Pronunciation

(ul-na)

Notes

The ulna (along with the radius) is one of the two bones in the forearm. In the anatomical position, it is medial to the radius.

The ulna articulates with:

The ulna is broader proximally, and narrower distally.

Proximally, the ulna has a bony process, the olecranon process, a hook-like structure that fits into the olecranon fossa of the humerus. This prevents hyperextension and forms a hinge joint with the trochlea of the humerus. There is also a radial notch for the head of the radius, and the ulna tuberosity to which muscles can attach.

Distally (near the hand), there is a styloid process.