Muscle twitching is the presence of uncontrollable muscle contractions that might be temporary or chronic. When this occurs in the thumb, it can be referred to as thumb twitching, and it might occur for a variety of reasons, including overuse of the muscle from playing video games or texting, nutritional deficiencies, carpal tunnel syndrome or restricted blood flow. Other causes might include neurological disorders, side effects from prescription drugs, anxiety or a chronic state of tension. Muscle contractions are very common, and most cases of thumb twitching are benign, but ongoing twitching indicate a serious condition.
Repetitive motion injury is a very common cause of thumb twitching. Video game modules and remotes, cell phones and other electronic gadgets require unnatural and constant use of the thumb, irritating the nerves that control the thumb muscles. The thumb might exhibit annoying muscle contractions, tingling, burning pain or tendinitis from the constant stress.
Carpal tunnel syndrome, a type of nerve trauma in which the median nerve is unduly compressed, might cause thumb twitching but is usually associated with wrist pain or burning in the wrist joint. Repetitive motion injury and carpal tunnel syndrome usually are relieved when the offending actions are ceased, although carpal tunnel syndrome might have underlying causes ranging from genetic factors to more serious physiological factors such as fibroids.
Thumb twitching might be caused by an imbalance of electrolytes from nutritional deficiencies in the diet. A deficiency of calcium or magnesium has been shown to cause muscle spasms and cramps throughout the body, including in the thumbs. Drug side effects might also cause the fingers and thumbs to spasm. Drugs such as corticosteroids, estrogens, diuretics and caffeine stimulate muscles, which might initiate twitching. Extreme anxiety releases hormones that upset the balance of the nervous system, causing muscle spasms that might include the thumbs.
Chronic thumb twitching with a gradual loss of muscle coordination is usually a sign of more serious neurologic disorders. Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig’s disease, is a progressive and debilitating nerve disease. ALS symptoms usually begin with muscle spasms in the chest and rib area, which progress down the arm and sometimes afflict the thumb. Multiple sclerosis and Parkinson’s syndrome also affect the nerves that control the muscles, including the thumb. Although many cases of thumb twitching are benign and are caused by environmental factors, ongoing spasms that get more and more serious require medical diagnosis to determine the underlying cause.