Many people occasionally wake up to the feeling of pins and needles in one or both of their hands. The likeliest cause of these symptoms is compression of one or both of the main nerves (the median and ulnar nerves) that supply feeling and function to your hands. Compression of the median nerve at the wrist is called carpal tunnel syndrome. The most vulnerable point for the ulnar nerve to become compressed is at the elbow, because it is in this area where it is fairly superficial without a lot of muscle and fat to bury and protect it (hence, that uncomfortable feeling you get when you bang your elbow).
Nerves that branch out from the cervical spine travel and branch off to become the median and ulnar nerves that supply sensation and muscle power to the hands. They pass through the vertebrae of the neck, across the armpit, down to the bony elbow joints, and between the ligaments and bones of the wrist. If they come under pressure at any point along the way, the arm or hand may feel as if it has "fallen asleep."
This is most likely to occur if you sit or lie with your hands in one position for a long of time. That doesn't usually happen during the day, but it's common at night. Typical pressure points during sleep are the neck, elbows, and wrists. Your head may be in a position that causes the vertebral bones or discs or the muscles in your neck to press on the median and ulnar nerves. Lying on your back with elbows at your sides may create pressure on them at the elbow joints. And sleeping with both wrists bent forward can put pressure on the nerves at the wrists.
Some people experience the tingling often, and it is severe enough to wake them up. Certain conditions ? for example, rheumatoid arthritis and hypothyroidism ? can contribute to the symptoms. So can heavy or repetitive work with your hands. They could also be an early sign of carpal tunnel syndrome, which is caused by pressure on the median nerve at the wrist.
If you can relieve the tingling by shaking or rubbing your hands for a few minutes, that's a good sign: It means you likely don't have permanent nerve damage. Nevertheless, it would be nice to get an uninterrupted night's sleep. Some options for treatment include repositioning your head with a specialized pillow and physical therapy. After examining your wrists and elbows, your doctor may recommend wrist splints to keep your wrists straight during sleep, or pads to prevent pressure on your elbows. Sometimes a nonsteroidal anti-inflammatory drug such as ibuprofen (Motrin, Advil) or aspirin, or a steroid injection is needed to reduce swelling from inflamed wrist tendons. If none of these suggestions works, ask to be referred to a neurologist, physiatrist or orthopedic surgeon who specializes in treating hand conditions for a more extensive evaluation.
How often do you experience tingling in your hands while you sleep? What do you find helps prevent this problem?
Julie K. Silver, M.D., is an assistant professor in the Department of Physical Medicine and Rehabilitation at Harvard Medical School. She is also the Chief Editor of Books for Harvard Health Publications.
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