carpal tunnel syndrome. 1  a medical condition that is characterized by pain, numbness, etc. in the wrist, palm, fingers, and thumb, usually caused by repetitive hand movement, as in typing or knitting, which swells the tissue surrounding the nerve in a tunnel-like passage (carpal tunnel) in the wrist.
1 The radius is located laterally, nearer the thumb, and the ulna medially, nearer the little finger.The radius and the ulna have a styloid process at the distal end and are attachment sites for many muscles.  The radius is smaller than the ulna.
The joint between the proximal ends of the radius and the ulna, where the head of the radius rotates in a ring formed by the radial notch of the ulna and a ligament (annular ligament), is of this type. Similarly, a pivot joint functions in the neck as the heard turns from side to side.