What are trigger finger and trigger thumb?
The muscles of the forearm are attached to the end of the fingers by way of strong bands of connective tissue known as tendons. These tendons move the fingers by sliding through pulleys in the hand and fingers when the forearm muscles are contracted. Due to an injury or age-related changes in the tendon, a thickened nodule can develop, causing a restriction of the tendon’s ability to slide through the pulleys. This can lead to a ‘triggering’ as the tendon is forced through a pulley. Commonly, trigger fingers occur in individuals who suffers from systemic conditions including rheumatoid arthritis and diabetes.
Focal pain is felt directly over the tendon nodule which in many cases will be felt as a hard lump on palpation of the area. There is commonly ‘triggering’ of the tendon with gripping and other activities involving flexing the affected finger or thumb. In severe cases, the finger or thumb may get stuck in one position. Symptoms are normally worse in the morning after the finger or thumb has been immobile overnight.
How are trigger finger and thumb diagnosed?
Trigger finger or thumb can be reliably diagnosed by your doctor or physiotherapist by taking a history of your condition and by conducting a physical examination. The main feature on examination is a painful nodule within the tendon which triggers when the finger or thumb is flexed. X-rays and scans are not routinely required.
How are trigger finger and thumb treated?
Trigger finger and trigger thumb can be managed very effectively in almost all cases with non-surgical management.
Rest and use of a finger or thumb splint
Resting from any activities involving gripping and flexing the affected finger or thumb and resting the finger or thumb in a splint overnight allows and inflammation and pain in the tendon nodule to settle.
Corticosteroid injection therapy
For individuals with trigger finger or thumb who continue to suffer disabling symptoms in spite of an appropriate period of rest and activity modification, a corticosteroid injection can be offered as the next line of treatment. You can read more about local corticosteroid injections here.
Trigger finger release surgery is an effective option for individuals who:
- Have trialled a course of non-surgical management including two corticosteroid injections without success
- Have consistent, painful triggering or an inability to be able to move the finger or thumb freely preventing normal function
- Have ultrasound imaging confirming the diagnosis