Trigger Finger / Thumb
Date issued: December 2022
Review date: December 2024
Ref: A-561/NB/ED/Trigger Finger / Thumb
PDF: Trigger Finger Thumb final December 2022.pdf [pdf] 125KB
What is trigger finger or trigger thumb?
A trigger finger is a finger that becomes 'locked' after it has been bent (flexed).
It is difficult to straighten out and may 'click' when it is pulled straight. Sometimes there is mild pain and/or a small swelling at the base of the affected finger.
What causes trigger finger/thumb?
It is usually due to inflammation which causes swelling of a tendon or tendon sheath.
A tendon is a strong tissue that attaches a muscle to a bone.
A tendon sheath is like a tunnel that covers and protects parts of a tendon. Usually, the tendon slides easily in and out of the sheath as you bend and straighten the finger. In trigger finger the tendon cannot easily slide back in due to the swelling. The finger then remains bent (flexed) unless you pull it straight with your other hand.
Most cases occur for no apparent reason. In some cases, it occurs after you have used your palm a lot, for example after jobs which involved a lot of screwdriving or using tools that press on the palm. These can cause some inflammation in the palm.
What is the treatment for trigger finger/thumb?
Not treating is an option at first. Simply resting the hand and allowing any inflammation to settle may resolve the problem without the need for treatment.
Anti-inflammatory medication may help, for example ibuprofen. It can be used with paracetamol or as an alternative. There are many types and brands. They relieve pain and reduce inflammation and swelling (often the cause of the pain). You can buy ibuprofen at pharmacies or supermarkets without a prescription. The dose varies depending on your age and other medical problems. Side-effects sometimes occur with anti-inflammatory painkillers. Ask your doctor or pharmacist for advice.
A steroid injection into the tendon sheath is another option. It is usually combined with a local anaesthetic to make the injection less painful. Steroids work by reducing inflammation. Steroid injections may not have their full effect for several weeks.
A finger splint may be advised for a few days after the injection to rest the finger.
An operation may be helpful if the above does not work. You would need to be referred to a surgeon by your General Practitioner – this cannot be done through the Emergency Department.
