Numbness in the fingers is not only an aggravation, but can be a limitation to hand function. It can also pose a risk for injury from severe cold and heat as well as sharp objects because of diminished sensation. Numbness and tingling in the fingers can be caused by several different factors.
Carpal Tunnel Syndrome
Carpal Tunnel Syndrome is one of the most common causes of numbness in the thumb and fingers. This condition arises from compression of a nerve in the wrist called the median nerve. This nerve passes over the wrist on the palm side before it divides and branches to the fingers.
Compression of this nerve results in a decrease in the size of the opening through which the nerve, together with several tendons responsible for finger functions, passes. The carpal bones on one side, and the transverse carpal ligament on the other combine to form the tunnel through which these components traverse.
Factors such as repetitive stresses, direct injury and even pregnancy can result in pressure being exerted upon these structures. When this occurs, nerve impulses passing from the arm to the fingers are delayed. The more severe the compression of the nerve, the slower the impulse transmission.
In extreme compressive conditions, death of the nerve tissue can be a distinct possibility if the pressure is not relieved, usually through surgery. Less severe cases can often be treated by the use of wrist splints, anti-inflammatory drugs and occasionally, cortisone injections.
Making changes in workplace environments can also benefit those who suffer as a result of poor ergonomics, such as keyboard and computer operators.
Diabetes
Diabetes is a disease that can affect any body organs and tissues. In the long-term, people may suffer from the deteriorating effects of the disease with a complication known as diabetic peripheral neuropathy. This neuropathy can affect upper and lower extremities alike, but tends to be seen more in the lower, especially the feet and toes. Peripheral neuropathy in the hands and fingers is not uncommon and the symptoms are similar, with decreased or absent sensation and difficulty grasping objects. The risk of pressure ulcers is present due to lack of sensation from objects or clothing exerting excessive pressure on the tissues. There is also the risk of thermal injury from extreme cold or heat as well.
Raynaud's Phenomenon
Raynaud's phenomenon is described as a condition in which extreme cold and even emotional stresses can induce spasm of the blood vessels in the hand and fingers causing a blockage of the blood flow to the fingers, as well as other body structures.
When this occurs, the fingers take on a whitish hue and sensation is all but absent. Numbness and tingling, even a stinging sensation, can occur during periods of warming and stress relief.
Even though this is more a vascular problem than a neurological one, the numbness that results is equally aggravating and uncomfortable.
