Anatomy of Tendons that Help in Bending the Fingers
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.
What is Trigger Finger?
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, like pulling and releasing the trigger on a gun, hence the name trigger finger.
Causes of Trigger Finger
Trigger finger is caused by the 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.
The 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 a 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.
Signs and Symptoms of Trigger Finger
The 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 and are unable to straighten when the nodule grows large and gets stuck in the pulley
- The symptoms are worse in the morning.
Impact of Trigger Finger
Long-term complications of untreated trigger finger can include permanent digit swelling and contracture, as well as tearing of the tendon or rupture.
Diagnosis of Trigger Finger
Trigger finger is diagnosed based on the medical history and a physical examination, without any special testing required.
Treatment for Trigger Finger
Your surgeon will recommend conservative treatment options to treat trigger finger symptoms which 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
- Avoiding activities that tend to bring on the symptoms
- Performing strengthening and stretching exercises with the affected finger
- Occupational therapy including massage, heat, ice and exercises to improve the finger
- Applying ice over the affected finger over a towel for 5-15 min, 3-4 times daily
- Using non-steroidal anti-inflammatory drugs (NSAIDs) to relieve pain and inflammation
- Administering steroid injections into the affected finger to reduce the inflammation