The ability to bend the fingers is governed by supportive tendons that connect muscles to the bones of the fingers. The tendons run along the length of the bone and are kept in place at intervals by tunnels of ligaments called pulleys. When the fingers bend or are straightened, a slippery coating called tenosynovium helps the tendons smoothly glide through the ligaments with reduced friction.
Inflammation in the tenosynovium leads to a condition called trigger finger, also known as stenosing tenosynovitis or flexor tendonitis, where one of the fingers or thumb of the hand is caught in a bent position. The affected digit may straighten with a quick snap, similar to pulling and releasing the trigger on a gun, hence the name trigger finger.
What are the causes of trigger finger?
Trigger finger is caused by inflammation of the tenosynovium. Inflammation forms a nodule and makes it difficult for the tendon to glide smoothly within its sheath, causing "catching" of the finger in a bent position and then suddenly releasing the finger straight.
Other causes of trigger finger can include the following:
Repetitive Motion: Individuals who perform heavy, repetitive hand and wrist movements with prolonged gripping at work or play are believed to be at high risk of developing trigger finger.
Medical Conditions: Conditions associated with developing trigger finger include hypothyroidism, rheumatoid arthritis, diabetes, and certain infections such as tuberculosis.
Gender: Trigger finger is more common in females than males.
What are the signs and symptoms of trigger finger?
Commonly reported symptoms associated with trigger finger include the following:-
- Pain and tenderness over the inflamed tendon nodule
- Bent finger suddenly pops out and straightens
- "Popping" or "clicking" sound or sensation when the nodule moves through the pulley
- Finger feels stiff and sore
- Finger gets locked with inability to straighten when the nodule grows large and gets stuck in the pulley
- Symptoms are worse in the morning
Long-term complications of untreated trigger finger can include permanent digit swelling and contracture, as well as tearing of the tendon or rupture
How is trigger finger diagnosed?
Hand and wrist conditions should be evaluated by an orthopedic hand surgeon for proper diagnosis and treatment. Trigger finger is diagnosed based on the medical history and a physical examination without any special testing.
What are the treatment options?
Your surgeon will recommend conservative treatment options to treat trigger finger symptoms. Treatment options will vary depending on the severity of the condition.
Conservative treatment options may include the following:
- Treating any underlying medical conditions that may be causing the problem, such as diabetes or arthritis.
- Resting the hand for 2-4 weeks or more by avoiding repetitive gripping actions. Avoid activities that tend to bring on the symptoms.
- Strengthening and stretching exercises with the affected finger may be suggested.
- Occupational therapy may be recommended for massage, heat, ice and exercises to improve the finger.
- Ice over the affected finger may help symptoms. Apply ice over a towel for 5-15 min, 3-4 times daily.
- Non-steroidal anti-inflammatory drugs (NSAIDs) may help to relieve pain and inflammation.
- Steroid injections into the affected finger may help reduce the inflammation.
If conservative treatment options fail to resolve the condition and symptoms persist for 6 months or more and your quality of life is adversely affected, your surgeon may recommend you undergo a surgical procedure to release the tendon.Percutaneous trigger finger release surgery is a minimally invasive procedure performed under local anesthesia. Your surgeon makes one small incision to the affected finger area, about an inch long, and releases the tight portion of the flexor tendon sheath.
Trigger finger is a repetitive stress injury that occurs with constant repetitive actions at work or play. It is commonly seen in farmers, musicians and industrial workers. The condition can be effectively treated with conservative or surgical treatments. Your doctor will be the best person to advise you on your options and the type of treatment best suited for you.