Carpal tunnel syndrome (CTS) is a common condition that can cause pain, tingling, numbness, and weakness in the hands and wrist. It is caused by pressure on the median nerve in your wrist. The pressure is most noticeable when the wrist is fully extended or flexed.
The median nerve and several tendons run from your forearm to your hand. They pass through a small space in your wrist called the carpal tunnel. The median nerve controls movement and feeling in your thumb and first three fingers (index, middle and ring fingers).
Anything that squeezes or irritates the carpal tunnel space’s median nerve may lead to carpal tunnel syndrome. Things that may contribute to this condition include:
- Frequent, repetitive, small movements. This includes typing or using a keyboard, which can cause the membranes around the tendons to swell.
- Work-related activities that involve forceful or repetitive hand movements, hand-arm vibration, and working for long periods in the same or awkward positions.
- Sports and physical activities that involve frequent, repetitive, grasping movements with the hands.
- Conditions or illnesses that can cause or contribute to arm pain or swelling in the joints and soft tissues in the arm, or to reduced blood flow to the hands. These include arthritis, osteoarthritis, or rheumatoid arthritis, gout, obesity, diabetes, lupus, and hypothyroidism.
- Conditions or injuries of the wrist such as broken wrist bones, dislocated bones, strains, sprains, new bone growth from healing bones, or bone spurs.
- A family history of carpal tunnel syndrome.