Tendons are a strong band of fibrous connective tissues that link the muscle to the bone. These tendons are protected by another layer of connective tissues called the tendon sheaths. When the tendon sheaths on the finger are inflamed, the normal gliding motion of the tendon through the tendon sheath is disrupted. When the tendon sheath is irritated or inflamed for a long period, the tendons can be scarred, thickened and may develop bumps or nodules. This can interfere with the tendons' movement, which can lead to stiffness and pain in the finger, a condition known as trigger finger.
While the causes of trigger finger are not always clear, they may include rheumatoid arthritis, gout and diabetes. Injury to the palm or base of the finger may also cause trigger finger.
Risk factors for trigger finger
Factors that put you at risk of developing trigger finger include:
- Occupation and hobbies – People whose occupation or hobby requires them to regularly execute repetitive and prolonged hand gripping have a higher risk of developing trigger finger.
- Sex – Trigger finger is a condition more common in women. Though it is only a theory, it is said that hormone changes in women play a role in the development of trigger finger. Changes in oestrogen levels have something to do with increased swelling in tendons and joints. This makes trigger finger more likely for women.
- Pre-existing health conditions – People with rheumatoid arthritis and diabetes are at risk of developing trigger finger. People with diabetes are at a higher risk of developing trigger finger as it is said that chronically elevated blood glucose levels can make the connective tissues glycated. This causes damage that can lead to a trigger finger.