Latin incisura ulnaris radii TA A02.4.05.019 | Dorlands/Elsevier 12447593 FMA 75082 | |
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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.
References
Ulnar notch of the radius Wikipedia(Text) CC BY-SA