Slide show below:
The ulnar nerve runs from the neck under the clavicle (collar bone) done the arm, through a tunnel in the elbow and into the hand. It provides feeling for the ring and small finger. It also provides electricity to the small muscles in the hand responsible for fine motor control. When you hit your “funny bone”, you are hitting the ulnar nerve which apparently is funny to everyone except you!
The nerve may be pinched or compressed as it goes through the elbow tunnel (cubital tunnel). There are different levels of severity from mild and moderate to severe. With mild, the tingling is intermittent and there is no muscle weakness. With severe, there is constant numbness and muscle weakness with atrophy. Moderate is somewhere in-between. History and exam are combined with nerve testing to make the diagnosis and determine severity. Sometime numbness is from a different source such as the neck.
Treatment typically depends on severity. Knowing the “wiring” – that the little finger numbness is related to the nerve going through the elbow is already a good start. One needs to avoid direct pressure or prolonged flexion of the elbow. More severe compression is treated with surgery. The most common surgeries are nerve release with either anterior transposition or medial epicondylectomy. Recently there has been a move toward only releasing the nerve without dealing with the “stretch” part of the problem. If surgery is being considered, a discussion with your doctor can be made about the advantages and disadvantages of each technique.
It is important to release the nerve before there is permanent damage or the results will not be as good. The nerve is composed of tissue similar to the brain and once injured can only partially recover. Regarding surgery, the decision is based on severity and is a combined decision with the patient and the surgeon.
For more information, see the slide show below: