What would cause numbness and tingling in my little finger?

DEAR DOCTOR K:

I’m bothered by numbness and tingling in my little finger and general weakness in my right hand. Could I have carpal tunnel syndrome?

DEAR READER:

Based on your description, I’d say you have cubital (not carpal) tunnel syndrome. Another name for this condition is ulnar neuropathy.

Cubital tunnel syndrome, like carpal tunnel syndrome, is a “pinched nerve” problem. The affected nerve is the ulnar nerve. That nerve starts in your neck, enters your arm, and passes through the inner side of your elbow (behind your funny bone) on its way to your hand. In fact, when you hit your funny bone and feel a shooting pain down your arm and into the hand, it’s because you hit the ulnar nerve, not the bony cradle that the nerve passes through.

The ulnar nerve passes through a tunnel made of fibers (the cubital tunnel) en route to your hand. If the tunnel gets narrow, it puts pressure on the nerve. This pressure causes numbness, tingling, weakness or pain in your ring finger or little finger. (In contrast, the more common carpal tunnel syndrome affects the thumb, index and middle fingers.) Cubital tunnel syndrome can also cause your hands to become weak and clumsy.

Tasks that require you to extend and flex your elbow repeatedly can irritate and inflame the ulnar nerve. Leaning or resting on your elbow for long periods can also put pressure on the nerve; so can holding a phone to your ear for longer periods each day. Sleeping with bent elbows may also aggravate the problem.

The most effective way to treat cubital tunnel syndrome is to change the actions that may have triggered the problem. For instance, switch to a headset-style phone and remove armrests from your office chair. Avoid leaning on your elbow while driving or when seated. Also avoid keeping your elbow flexed more than 90 degrees, or repeatedly bending and straightening your elbow.

Try sleeping on your side with a pillow supporting the entire length of your arm. Try wrapping a towel around your elbow or wearing a splint at night to keep it straight while you sleep. If you can’t avoid bumping your elbow and causing pain several times a day, try wearing a soft elbow pad to protect the nerve against such trauma. Medications to reduce swelling may help.

Most people improve with the conservative approaches I discussed. If you don’t, your doctor may suggest surgery. The most common type of surgery is ulnar nerve release: The surgeon cuts open the tunnel that is pinching the nerve. But it would be unusual for me to send a patient with cubital tunnel syndrome (or ulnar neuropathy) to a surgeon. Usually, the simple approaches do the trick.