The Real Cause of Carpal Tunnel Syndrome
What's the real underlying cause of carpal tunnel syndrome? Is it genetics? Repetitive workload? Sudden change in temperature? Pregnancy? Low thyroid function? These are just a few of the potential risk factors for CTS.

In this study, a search of the published literature on CTS is performed. The authors were looking for scientific evidence to find out which risk factors linked to CTS are the strongest.

They used the Bradford Hill criteria to evaluate scientific data on the causes of CTS. Quality and strength of the data was evaluated for 117 articles. They were searching for a direct causal link between structural or genetic risk factors, biologic factors, and environmental or occupational risk factor and CTS. Other potential risk factors such as age, race, and gender were also reviewed.

After analyzing all the data, the authors reported the following:

  • CTS is mostly structural, genetic, and biologic
  • Work factors such as repetitive hand use plays only a minor role (if any) in CTS
  • There is no evidence that typing is linked with CTS
  • Age, gender (female), obesity, and diabetes are important secondary risk factors

    The results of this study agree with a previous important study of adult twins in the United Kingdom (Hakim and associates). The Hakim study showed that genetic factors account for half the risk of CTS. There is strong support that CTS is a structural, genetic disease process.

    Repetitive and occupational activities and frequent computer use were not strongly linked as risk factors for CTS. The authors do not advise labeling CTS as a work-related disease without strong scientific support. To date, such support is lacking.
    References
    Santiago Lozano-Calderón, MD et al. The Quality and Strength of Evidence for Etiology: Example of Carpal Tunnel Syndrome. In The Journal of Hand Surgery. April 2008. Vol. 33A. No. 4. Pp. 525-538.