Ulnar tunnel syndrome is caused by pressure on the ulnar nerve at the
wrist. This nerve is found on the pinkie-finger side of the wrist.
Overuse or repetitive use of your hands or wrist may cause swelling or
thickening of the tissues close to the ulnar nerve. Swelling from a ganglion
can also affect the ulnar nerve. Bicycle riders may develop ulnar tunnel
syndrome from holding on to the handlebars.
Symptoms of ulnar tunnel syndrome include weakness, numbness and
tingling, and pain in the ring finger, pinkie finger, or both.