Ulna, ulnar nerve, ulnar tunnel syndrome..

Ulna   Forearm bone that runs from the elbow to the pinky finger side of the wrist. The other forearm bone is called the radius.

Ulnar nerve   This nerve controls both the movement and sensation of the little finger (pinkie) and half of the ring finger. It follows the similar path to the median nerve until it reaches the elbow and then it travels behind the back of the inside of the elbow (the cubital tunnel). This point of the ulnar nerve is very exposed and referred to as the 'funny bone'. At the wrist it passes through the ulnar tunnel. Injury to the nerve at the ulnar tunnel can create numbness and weakness in the pinkie (fifth finger).

Ulnar Tunnel Syndrome   Numbness and weakness in the fifth finger caused by nerve compression as the ulnar nerve passes into the wrist. Commonly caused by pressing the heel of the wrist against a hard desk while typing or using a mouse. See 'Setting up your workstation' for tips on how to avoid this type of problem.

Upper Limb Disorders (ULD) or Work Related Upper Limb Disorders (WRULD)   It is a blanket term which covers many conditions which cause pain or discomfort in the hands, fingers arms, elbows and shoulders. ULD and WRULD are sometimes referred to Repetitive Strain Injury (RSI). What is RSI?.