Carpal tunnel syndrome (CTS) is a is caused by the entrapment of the median nerve in the wrist that then causes paresthesia, pain, numbness, and other symptoms in the distribution of the median nerve. It appears to be caused by a combination of genetic and environmental factors. Some of the predisposing factors include: diabetes, obesity, pregnancy, hypothyroidism, and heavy manual work or work with vibrating tools. The main symptom of CTS is intermittent numbness of the thumb, index, long and radial half of the ring finger. Long-standing CTS leads to permanent nerve damage with constant numbness, atrophy of some of the muscles of the thenar eminence, and weakness of palmar abduction.