If you’ve ever woken up, only to realize that your hand is numb, you’re not alone. This fairly common phenomenon is due to a nerve (or two or three) in the arm being stretched or clamped due to your sleeping position. The most commonly affected nerve is the ulnar nerve, which wraps around the elbow joint, making it prone to irritation. When that ulnar nerve is jarred, due to hitting your elbow just the right — or wrong — way, it’s sometimes called the “funny bone” sensation. While there is nothing really funny about it, the related numbness usually affects the pinky finger and part of the ring finger.
Frequently, this kind of stress related to the ulnar nerve results from a flexed elbow position that is more than ninety degrees. This kind of strain is common for those who sleep in the fetal position, as well as for those who wrap a pillow around their heads while sleeping, or for those who sleep atop a flexed elbow. Our bodies often give us cues to move during sleep, thereby lessening the tension on the nerve. During an especially sound sleep, however, we can remain in such positions for extended periods of time, increasing the chances of nerve tension. Especially when people drink alcohol or take other sedatives before going to bed, awareness of stress is lessened, decreasing the chances of a changed position. (In fact, the effect of alcohol on this particular condition is so common that clinicians have referred to alcohol-induced nerve damage as a “Saturday night special.”)
When ignored, ulnar nerve irritation can cause serious problems and can even lead to nerve damage. While the early stages involve only temporary numbness, repeated stress on the nerve can eventually cause weakened muscles. To test your muscle strength, make a talking motion with your hand. If your ulnar nerve is stressed, the muscles of your ring and pinky fingers will be unable to hold the position; instead, they will bend involuntarily, raising above the other fingers that remain straight.
To allow those nerves to heal and muscles to regain strength, you’ll need to avoid stressing the ulnar nerve. You can do that by avoiding sustained bending of the elbow. If needed, an elbow brace that blocks the elbow from flexing too much can help. You can also reduce stress to the area by avoiding direct pressure on the elbow by making sure not to rest elbows on tables or other surfaces.
Sometimes, those kinds of conservative measures aren’t enough to make up for chronic stress that has built up over a long period of time. In that case, you’ll want to see a physician to try to uncover additional contributing factors. Nerve damage does not happen overnight, and it can take some time to heal.
PhysioDC of Washington, D.C.
Daniel Baumstark and his professional team of physical therapists operate a boutique physical therapy office in downtown Washington, D.C. From athletes to government officials, and from ballerinas to corporate executives, PhysioDC helps people recover, strengthen and return to healthy living. Visit their site or call them at 202-223-8500.
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