Trigger Finger

The fingers and thumb of each hand have tendons which run along their length. These tendons connect the digits to the forearm muscles. The tendons function to bend and straighten the digits, when the forearm muscles contract (shorten). The tendons are surrounded by a tube or sheath, which secretes fluid to lubricate the tendons and allow smooth movement. Trigger finger is a common condition in which either the sheath becomes inflamed or the tendons develop swellings. This prevents the smooth movement of the tendon within the sheath, which is described as ‘Triggering’.

You may have noticed that your finger or thumb appears stiffer and may lock down or jam in the palm of your hand, particularly first thing in the morning. When you try and straighten the finger it may be painful and move suddenly with a click. You may also have noticed a swelling or nodule at the base of the finger that moves when you move your finger. In some cases the finger is swollen and painful.

The cause of trigger finger is unknown. It can occur at any age and in both sexes. Some conditions are associated with an increased likelihood of developing it, such as diabetes and rheumatoid arthritis.

Diagnosis can often be made from the clinical history (the account of events and symptoms from the patient) and the clinical examination.

CRPS – complex regional pain syndrome, this is an uncommon but serious complication. It can on rare occasions leave you with a less function hand with on-going pain stiffness and swelling. See section on CRPS. The exact incidence or rate of CRPS after surgery is unknown. It probably occurs in a significant form in approximately 1-2% of cases

See also BSSH guidelines here

Surgery (‘trigger finger release’) involves dividing part of the tunnel around the tendon in the palm, through a small incision, allowing the tendon to move more freely. This is usually performed under a local anaesthetic by “freezing the skin” with an injection. A tourniquet (similar to a blood pressure cuff) may be applied to the arm to provide the surgeon with a blood-free field for surgery. An incision approximately 1-2cm long is then made in the palm of the hand (or over the base of the thumb in trigger thumb release). The surgeon divides the entrance to the tunnel in which the tendon runs. This stops the triggering and allows the inflammation to improve. The nodule is not removed. At the end of the procedure the incision is stitched with fine sutures and the hand put in a large bandage. This is usually removed after 48-72 hours.

In patients with rheumatoid arthritis the tunnel is released less frequently. Instead, if surgery is required the inflamed tissue (synovitis) around the tendon is removed and this often improves the pain and triggering. This is a more involved procedure and may be performed under general/regional anaesthesia.

In babies/children a general anaesthetic is required for surgery.

You should be fit to go home soon after the operation. The local anaesthetic will wear off after approximately 6 (6-36 hours) hours. Simple analgesia usually controls the pain and should be started before the anaesthetic has worn off. The bandage you will have on initially may make it difficult for you to eat and wash yourself, so you may need to arrange assistance.

You should keep your hand/arm elevated whenever possible over the first 48 hours after surgery. While sitting this is best achieved by placing your arm on pillows above the level of your heart. Light use of the hand is encouraged to maintain finger mobility.