You may be describing a test used to look for carpal tunnel syndrome (CTS) called the flick sign. This test is done by shaking the hands as if shaking down a thermometer. It's positive for CTS if the symptoms go away after shaking or flicking the hands. The flick sign is a highly sensitive and specific test for CTS.

The most common symptoms of carpal tunnel syndrome are pain, numbness, and tingling in the thumbs and first two fingers. Numbness in all fingers can also occur. Symptoms are usually worse at night and often wake patients up from a sound sleep.

Age (over 45 years old) and body size (obesity) are risk factors for CTS. CTS is also a common problem associated with other conditions such as pregnancy, diabetes, and thyroid problems. It may be a good idea to have your doctor take a look at you. Sometimes early diagnosis can help take care of the problem quickly and easily.