Alpha-lipoic acid for carpal tunnel syndrome

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^[1][2] 3-6% of people, and subjective symptoms are associated^[3] with anxiety, depression, and lower quality of life. The major biomechanical risk factors^[4] 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^[5] 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^[6] with CTS.

Compression of the median nerve may cause biochemical changes in the nerve that contribute to damage. Animal studies show that crushing^[7] rat nerves increases oxidative stress levels. Furthermore, humans with CTS show higher levels of oxidative stress both in their hand tendon^[8] and globally^[9]. These observations suggest that reactive oxidative species may play a role in the development and worsening of CTS, which means there may be a way to slow its progression: through antioxidants.

Alpha-lipoic acid (ALA) is a strong antioxidant candidate for managing CTS for several reasons. First, it doesn’t act on its own — ALA also regenerates several other antioxidants, such as vitamins C and E. These properties have led some^[10] researchers to dub it a “universal antioxidant.” Second, ALA can help^[7] with nerve recovery from crush injuries in rats. Some human trials^[11][12][13] have found it to help with CTS, too, but ALA is often combined with other supplements, making it difficult to determine the efficacy of ALA alone. The goal of the study under review was to test ALA’s efficacy as monotherapy in people with CTS who were candidates for surgical treatment.

Carpal tunnel syndrome (CTS) is a condition that can lead to numbness, pain, or tingling in certain parts of the hand as a result of median nerve compression. Compression can lead to oxidative stress, which in turn can cause further damage. The study under review tested whether the antioxidant alpha-lipoic acid (ALA) may help mitigate this process, and be of benefit to people with CTS who were candidates for surgery.