Trigger finger

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Trigger finger, or trigger thumb, is a type of stenosing tenosynovitis in which the sheath around a tendon in a thumb or finger becomes swollen, or a nodule forms on the tendon. In either case, the tendon can no longer slide freely through its sheath. Affected digits may become painful to straighten once bent, and may make a soft crackling sound when moved. More than one finger may be affected at a time, though it usually affects the thumb, middle, or ring finger. The triggering is usually more pronounced in the morning, or while gripping an object firmly.

It is called trigger finger because when the finger unlocks, it pops back suddenly, as if releasing a trigger on a gun. Risk factors for trigger finger include diabetes, gonococcal arthritis, swelling of the hand, work injuries involving prolonged grip or vibration, fractures of the hand and other circulatory problems.

The best way to prevent this problem from getting worse is to avoid triggering the finger, which in turn leads to more swelling and more triggering.

Treatment
Seeking help as soon as the triggering starts can greatly improve a patient's chances of getting rid of the problem sooner. A doctor may prescribe occupational therapy or physical therapy to alleviate the swelling that causes the triggering. A patient may be given a corticosteroid shot at the base of the offending finger and then sent to therapy, or sent to therapy first to deal with the problematic triggering and resulting swelling that results from the constant triggering

Some of the treatment options in occupational or physical therapy may include steroid iontophoresis treatment, splinting, therapeautic ultrasound to decrease swelling or phonophoresis (ultrasound with an anti-inflammatory dexamethasone cream). Some patients have received relief from Acupuncture. If conservative treatment does not help, the problem is often resolved by a relatively simple surgical procedure (usually outpatient, under local anesthesia). The surgeon will cut the sheath that is restricting the tendon.

Treatment may include a non-steroidal anti-inflammatory drug, hand splinting, corticosteroid injection directly around the tendon and sheath, or surgical release of the sheath. - But corticosteroid injections are usually only a temporary solution, and usually make the condition worse in the long term.

Recovery
If therapy resolves the triggering, the patient can expect full recovery, as long as the affected finger(s) do not experience constant triggering. The goal is to prevent recurrent symptoms and triggering that can exacerbate the swelling, causing a vicious circle.

If surgery is performed on the finger, the patient can expect a pretty good recovery, as the sheath is cut away and there is nothing left to restrict tendon glide. The surgeon will instruct the patient on post-op limitations and motions to avoid. It is generally considered minor surgery and most surgeons recommend only a day or two of rest, followed by immediate and active use of the hand.

Prevention
Most people do not realize there is a problem until the swelling in the finger has built up to the point of causing mechanical disruption of the tendon glide in the tendon sheath.

Common risk factors for trigger finger include use of vibratory tools, repetitive motions of the hand or fingers or certain diseases that affect the circulatory system, like diabetes and hypothyroidism. Using anti-vibration gloves for work, taking frequent rest breaks or changing positions, and keeping any diabetes or hypothyroidism under control reduce the risk of developing the condition.