A common cause of tingling and numbness in the ring and small finger is cubital tunnel syndrome. Cubital tunnel syndrome refers to a problem related to compression of the ulnar nerve at the elbow within the cubital tunnel. Compression of the ulnar nerve will cause tingling and numbness, coordination disturbances in the small muscles of your hand, and weakness of hand grip and of pinch strength.
The ulnar nerve runs behind the elbow in a bony groove of the humerus (the long bone of the upper arm) with a ligament over the top, forming the cubital tunnel. Just past the elbow, the nerve then goes through the flexor carpi ulnaris muscle into the forearm and continues into the hand, giving both sensation and muscle function to the hand. Increased pressure on the ulnar nerve is produced by bent elbow positions, and the nerve is further compressed when leaning on the elbow.
You probably have felt the effects of nerve compression ‚ÄĒ when your foot falls "asleep" or when you hit your "funny bone". The changes in the nerve produced by pressure will progress with increased force of compression and/or length of time of compression.
The changes that occur in the nerve will be reflected in the symptoms that you feel in your hand. In the early stages, your symptoms will be mild and occur only occasionally. As the nerve compression progresses, the tingling and/or numbness to your small and ring finger will occur more often and with less time in irritating positions. You also may feel pain on the inside of your elbow and aching of the muscle along the inside of the forearm.
The first strategy of treatment is to understand the activities and positions that cause your symptoms and then to try avoiding these positions. By changing your body mechanics, you will take pressure off the ulnar nerve. Positions that place the elbow in bent postures (flexion) will increase pressure on the ulnar nerve, while elbow-straight positions (extension) will decrease the pressure. Most people sleep with their arms and hands in curled-flexed positions, compressing the nerve. Therefore, the first step of non-operative treatment is to protect the ulnar nerve by wearing an elbow pad at night, cushioning the ulnar nerve from direct pressure. Stretching exercises at the elbow/forearm/wrist may be helpful in patients with tightness of the flexor carpi ulnaris muscle.
If nonoperative treatment is going to be successful in relieving symptoms, you will notice a decrease in your symptoms within four to eight weeks. However, it may take many months to completely relieve your symptoms. If you do not notice any relief or if you have muscle wasting, surgical management is recommended.
Although there are many surgeries for the treatment of cubital tunnel, the anterior transmuscular transposition of the ulnar nerve is the operation that we recommend. This operation removes the pressure from the ulnar nerve and moves the nerve to a position in front of the elbow within the flexor pronator muscle mass. The operation usually is done on an outpatient basis with an anesthetic to your arm. In some cases, it might require an overnight stay in a hospital.