Ulnar notch of the radius

"Sigmoid cavity" redirects here. For Greater sigmoid cavity, see Trochlear notch.

The articular surface for the ulna is called the ulnar notch (sigmoid cavity) of the radius; it is in the distal radius, and is narrow, concave, smooth, and articulates with the head of the ulna forming the distal radioulnar joint.

Ulnar notch of the radius
Bones of left forearm. Anterior aspect. (Ulnar notch visible but not labeled.)
Details
Identifiers
Latin	incisura ulnaris radii
TA98	A02.4.05.019
TA2	1228
FMA	75082 23530, 75082
Anatomical terminology [edit on Wikidata]