Carpal tunnel syndrome or CTS is a painful and debilitating condition of the hand and arm caused due to pinched or pressed nerves in wrist (median nerve). Carpal is derived from the word, carpus (meaning wrist), and taken from the Greek word, karpos. In medical jargon, the carpus refers to an assembly of eight small bones that lie side-by-side in the wrist – in two rows – which join the forearm to the hand. The tunnel is a narrow passageway for nine (some anatomists say, ten) tendons and one nerve (the median nerve – so called, since it lies in the middle of the forearm and the wrist), to pass from the forearm to the hand. This passageway lies on the carpal bones and is roofed by a strong ligament, the flexor retinaculum. In the case of CTS, a group of symptoms occur together and it is therefore called a syndrome.