Risk factorsBy Mayo Clinic staff
A number of factors have been associated with carpal tunnel syndrome. Although by themselves they don't cause carpal tunnel syndrome, they may increase your chances of developing or aggravating median nerve damage. These include:
- Anatomic factors. A wrist fracture or dislocation that alters the space within the carpal tunnel can create extraneous pressure on the median nerve. Also, carpal tunnel syndrome is generally more common in women. This may be because the carpal tunnel area is relatively smaller than in men and there's less room for error. Women who have carpal tunnel syndrome may also have smaller carpal tunnels than women who don't have the condition.
- Nerve-damaging conditions. Some chronic illnesses, such as diabetes and alcoholism, increase your risk of nerve damage, including damage to your median nerve.
- Inflammatory conditions. Illnesses that are characterized by inflammation, such as rheumatoid arthritis or an infection, can affect the tendons in your wrist, exerting pressure on your median nerve.
- Alterations in the balance of body fluids. Certain conditions — such as pregnancy, menopause, obesity, thyroid disorders and kidney failure, among others — can affect the level of fluids in your body. Fluid retention — common during pregnancy, for example — may increase the pressure within your carpal tunnel, irritating the median nerve. Carpal tunnel syndrome associated with pregnancy generally resolves on its own after the pregnancy is over.
- Workplace factors. It's possible that working with vibrating tools or on an assembly line that requires prolonged or repetitive flexing of the wrist may create harmful pressure on the median nerve, or worsen existing nerve damage. But the scientific evidence is conflicting and these factors haven't been established as direct causes of carpal tunnel syndrome. There is little evidence to support extensive computer use as a risk factor for carpal tunnel syndrome, although it may cause a different form of hand pain.
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