Carpal Tunnel Syndrome
Carpal tunnel syndrome (CTS) occurs when the median nerve, which runs from the forearm into the palm of the hand, becomes pressed or squeezed at the wrist. The carpal tunnel—a narrow, rigid passageway of ligament and bones at the base of the hand—houses the median nerve and the tendons that bend the fingers. The median nerve provides feeling to the palm side of the thumb and to the index, middle, and part of the ring fingers (although not the little finger). It also controls some small muscles at the base of the thumb.
Sometimes, thickening from the lining of irritated tendons or other swelling narrows the tunnel and causes the median nerve to be compressed. The result may be numbness, weakness, or sometimes pain in the hand and wrist, or occasionally in the forearm and arm. CTS is the most common and widely known of the entrapment neuropathies, in which one of the body’s peripheral nerves is pressed upon.
Symptoms usually start gradually, with frequent burning, tingling, or itching numbness in the palm of the hand and the fingers, especially the thumb and the index and middle fingers. Some carpal tunnel sufferers say their fingers feel useless and swollen, even though little or no swelling is apparent. The symptoms often first appear in one or both hands during the night, since many people sleep with flexed wrists. A person with carpal tunnel syndrome may wake up feeling the need to “shake out” the hand or wrist. As symptoms worsen, people might feel tingling during the day. Decreased grip strength may make it difficult to form a fist, grasp small objects, or perform other manual tasks. In chronic and/or untreated cases, the muscles at the base of the thumb may waste away. Some people are unable to tell between hot and cold by touch.
Carpal tunnel syndrome is often the result of a combination of factors that reduce the available space for the median nerve within the carpal tunnel, rather than a problem with the nerve itself. Contributing factors include trauma or injury to the wrist that cause swelling, such as sprain or fracture; an overactive pituitary gland; an underactive thyroid gland; and rheumatoid arthritis. Mechanical problems in the wrist joint, work stress, repeated use of vibrating hand tools, fluid retention during pregnancy or menopause, or the development of a cyst or tumor in the canal also may contribute to the compression. Often, no single cause can be identified.
A wrist sprain is a common injury. There are many ligaments in the wrist that can be stretched or torn, resulting in a sprain. This occurs when the wrist is bent forcefully, such as in a fall onto an outstretched hand.
Symptoms of a wrist sprain are:
- Tenderness and warmth around the injury
- Feeling a popping or tearing in the wrist
As mentioned above, a wrist sprain usually occurs with a fall – a common injury for all sorts of athletes, as they instinctively put out their hand to break their fall. The injury occurs when the force of impact bends the wrist back toward the forearm.
The most common fracture to the wrist occurs to the distal radius, the end of the larger of the two arm bones at the thumb-side of the wrist. Distal radius fractures usually happen about one inch from the end of the radius. It is prone to injury when you fall on an outstretched hand or if there you have low bone density or osteoporosis.
The injury causes pain, swelling, and bruising and can create a deformed appearance to the wrist.
The most common cause of a distal radius fracture is a fall onto an outstretched arm. Osteoporosis (a disorder in which bones become very fragile and more likely to break) can also be a contributing factor, making a relatively minor fall result in a broken wrist.
Ganglion cysts are a non-cancerous mass or lump the usually occur in the back or front of the wrist or in the fingers. They are fluid-filled capsules that arise from joint linings or tendon sheaths. They are benign, often painless and many do not require treatment. However, if the cyst is painful or interferes with normal function, it may be made smaller by removing the fluid with a needle (aspiration), or removed surgically.
The ganglion cyst usually appears as a bump (mass) that changes size. It is usually soft, anywhere from 1-3 cm in diameter, and doesn’t move. The swelling may appear over time or appear suddenly, may get smaller in size, and may even go away, only to come back at another time.
The size of a cyst can fluctuate, often getting larger when you use that joint for repetitive motions. Ganglion cysts usually are painless. But if a cyst presses on a nerve — even if the cyst is too small to form a noticeable lump — it can cause pain, tingling, numbness or muscle weakness.
The cause of ganglion cysts is not known. One theory suggests that trauma causes the tissue of the joint to break down, forming small cysts that then join into a larger, more obvious mass. The most likely theory involves a flaw in the joint capsule or tendon sheath that allows the joint tissue to bulge out.