Trigger finger or stenosing tenosynovitis is the progressive stricture or narrowing of the protective sheath surrounding the tendon of an affected finger or thumb. This protective sheath is lined by the tenosynovium (a layer of tissue), which releases a lubricating fluid that facilitates the tendon to glide smoothly through the various pulleys of the hand when the finger is bent and straightened. When degeneration of the tenosynovium occurs the tendon moves through the sheath with difficulty and results in tendon swelling.
Tendon swelling impairs the movement of the affected finger that may seem stiff and click when moved. The finger will click, catch (trigger') or lock in a bent position and then unlock, suddenly popping straight. This type of action is similar to releasing the trigger on a gun and is commonly referred to as "trigger finger." In most cases, the thumb, middle or ring finger is affected and may involve two or more fingers.
How can you tell that you may have trigger finger? What are the usual signs and symptoms? Some patients experience creaking or clicking sensations when moving the fingers and are often slightly swollen and feel tender to pressure. For those with prolonged inflammation, scarring and thickening (fibrosis) occurs and bumps (nodules) can form.
Who is more likely to develop trigger finger? Trigger finger is commonly seen more in women than in men and with those who have diabetes. Other medical conditions that may increase your risk of developing trigger finger are rheumatoid arthritis, hypothydroidism, and amyloidosis. Also, as in the case of carpal tunnel syndrome, trigger finger is often speculated to be associated with work activities or hobbies that require repetitive gripping actions for extended periods of time, however, there is little scientific evidence to support this.
When should you seek medical advice? If you experience stiffness or catching in a finger joint you should have a medical doctor perform a physical evaluation on the affected hand. If trigger finger is diagnosed, treatment options include rest, modifying hand usage, splinting or finger exercises for mild cases. Medication with nonsteriodal anti-inflammatory drugs (NSAIDs), steroid injection, percutaneous trigger finger release procedure or surgery is recommended to for more severe cases.
After treatment, would the symptoms return? Although there is no cure for trigger finger, as the underlying problem will still persist, recurrent triggering is unusual after successful injection and rare after successful surgery.