Have you ever awoken to a numb hand? This is the result of one or more of the nerves in the arm being either clamped or stretched due to sleeping position. One of the most common nerves involved in this type of numbness is the ulnar nerve, as it passes around the elbow joint in such a way that it is easily bothered.
Ulnar nerve irritation is commonly referred to as the “funny bone” feeling that results from hitting one’s elbow on a corner in just the right way. (The feeling of jarring your ulnar nerve certainly isn’t funny, someone should change the name.) Numbness is manifested in the pinky finger and in the lateral half of the ring finger. This is not to be confused with the median nerve, which provides sensation to the tips of the middle finger, index finger, and thumb.
Stress on the ulnar nerve from sleeping comes from keeping the elbow flexed, usually more than ninety degrees, for a long period of time. Sleeping in the fetal position, wrapping a pillow around your head with your arms, or sleeping on top of a flexed elbow can all result in ulnar nerve strain. Most of the time our body will give us cues to move in our sleep and lessen the tension on the nerve. If we are sleeping very soundly, however, we may stay in a bad position for too long. Drinking alcohol before going to bed is not a great idea because sedatives tend to lessen our awareness of stress while asleep. Clinicians have dubbed the phenomena of alcohol-induced nerve damage from sustained elbow flexion as the “Saturday night special.”
Ulnar nerve irritation can become quite a problem if it is not dealt with. The early stages of irritation present themselves mainly with the numbness described above. If the nerve is repeatedly stressed, the muscles that are innervated by the ulnar nerve will start to become weaker.
If you wake up with numbness in your fingers, try to make a “sock puppet” position with your hand (see Illustration #1, above right).
If the ulnar nerve is highly stressed, the muscles of the last two fingers will not be able to hold this position. The result will look something like Illustration #2, above right.
If this is happening to you, take steps to remove stress on the ulnar nerve. Try to avoid sustained elbow bending when sleeping. If you are unable to do this on your own, it is a good idea to purchase a soft elbow brace that blocks the elbow from flexing excessively. This type of brace can help to keep the elbow relatively straight when sleeping.
It is also a good idea to avoid placing any direct pressure on the elbow. Avoid resting your elbows on a table or other surface while typing or working.
If the abovementioned conservative ideas do not seem to be helping, it is a good idea to see a doctor to see if any other factors are contributing. Also realize that a nerve that is damaged will take an appreciable amount of time to heal.