Carpal tunnel syndrome (CTS) is caused by the compression of the median nerve in the wrist. The symptoms include numbness, tingling, or pain in certain parts of the hand innervated by the median nerve, as shown in Figure 1. It affects around 3-6% of people, and subjective symptoms are associated with anxiety, depression, and lower quality of life. The major biomechanical risk factors for developing CTS are repetitive motions and forceful motions of the hand, as well as the combination of these two movement patterns. Non-hand-related associations exist as well, such as not exercising, poor overall physical health, and lack of job satisfaction. Other disease states, such as hypothyroidism and diabetes, are also associated with CTS.
Compression of the median nerve may cause biochemical changes in the nerve that contribute to damage. Animal studies show that crushing rat nerves increases oxidative stress levels. Furthermore, humans with CTS show higher levels of oxidative stress both in their hand tendon and globally.