Carpal Tunnel Syndrome (CTS)

Carpal tunnel syndrome occurs when muscles and tendons in the hand put pressure on the median nerve in the wrist.   Causing pain, tingling, numbness and/or weakness in the hand.

The median nerve.    Runs from the forearm to the hand through a small space in your wrist called the carpal tunnel;  It controls movement of the thumb and adjacent 3 fingers, but not the little finger. 

The carpal tunnel.    A passageway located on the palm side of the wrist connecting the forearm to the hand. The flexor retinaculum is a fibrous ligament covering the carpal bones and forming the carpal tunnel together with the arched carpal bones of the wrist. Nine tendons connected to the flexor muscles of the forearm pass through the carpal tunnel and if any of these tendons swell or degenerate,  they can "pinch" the median nerve causing pain.

By OpenStax College - Anatomy & Physiology, Connexions Web site. http://cnx.org/content/col11496/1.6/, Jun 19, 2013., CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=30131518

Symptoms

•   Pain, tingling, numbness, and/or weakness in the hand - with pain sometimes radiating into forearm and shoulder

•   Symptoms in thumb, pointy finger, middle finger and thumb side of ring finger,  but NOT the little finger

•   Pain often more pronounced at night

•   Temporary relief by shaking the hand

Causes

Anything causing swelling that makes the carpal tunnel smaller - including:

•     Making repetitive movements with the hand or wrist - especially if the hand is bent downwards (i.e. lower than the wrist). Such activities include excessive /prolonged keyboarding, clicking a mouse button, excessive use of pruning shears, repetitively lifting heavy weights, scrubbing, using vibrating hand tools, twisting a screwdriver

•    Inflammatory conditions / illnesses - such as pregnancy, rheumatoid arthritis, diabetes,  hypothyroidism, gout

A Harvard study suggests that there may be a genetic disposition to CTS