CTS is one of the several names for painful and disabling injuries to the thumb and fingers, and sometimes to the wrists, elbows and other joints. It is also known as cumulative trauma disorder, occupational neuritis, repetitive stress injury (RSI) or overuse injury. The warning signs are tingling and numbness in the affected joints-typically the fingers-especially after a regular workday, before sleep or on wakening.

Left untreated, the symptoms progress to persistent pain and aching in other areas such as arms and hands. CTS can eventually lead to the inability to grip things firmly and use your hands in a normal way. If you experience similar tingling and numbness in your feet, ankles and lower legs, the condition is called tarsal tunnel syndrome.