Trigger Finger / Thumb (Stenosing Tenovaginitis)
A trigger digit sufferer will experience discomfort or pain in the palm of the hand at the base of the affected finger(s) and often a clicking feeling when moving the digit, especially when bending and straightening. The digit may, in fact, get caught down in the palm, and it may be necessary to pull it straight again with a painful click. In a milder form of this condition the clicking and catching down in the palm may be absent, but the discomfort is present. Trigger finger or thumb can come on gradually, or occasionally rapidly, and may resolve spontaneously over time or remain indefinitely without treatment.
Who gets triggering?
Trigger finger is a very common hand condition affecting females and males of all ages. Infants and middle-aged women are particularly prone, and it is more common in people who have diabetes. It is quite common in patients who have carpal tunnel syndrome.
What causes triggering?
The flexor tendons that bend your fingers run within a tunnel called the fibrous flexor sheath, from the end of your palm into your finger as shown in the diagram below. The mouth of the sheath (A1 pulley) is narrower than the main part of the tunnel. In a trigger digit, a small swelling develops in the tendon which catches in the mouth of the sheath as the tendon glides in and out of the sheath. The clicking feeling represents the swelling catching at the mouth flexor sheath. The cause of the majority of swellings causing a trigger digit is not known, however fortunately, there is an effective treatment
A trained medical practitioner can diagnose trigger finger by clinical assessment. It is rare for any additional tests to be required although occasionally an ultrasound can provide additional useful information.
Trigger Finger Treatment Options
Non Operative Treatment
Should a trigger digit be mild and resolving it is entirely reasonable to let the condition heal spontaneously; this can be aided by resting the hand and avoiding repetitive hand work for approximately a week. For more severe and non resolving triggering, the main treatment options are hand therapy and steroid injections. Hand therapy involves exercises and at times the use of splints.
Steroid injections involve injecting minuscule amounts of steroid into the affected area. The steroid remains at the injection site and aims to reduce the swollen area in the tendon. A single injection resolves a triggering digit in over 70% of cases, and a further one or two injections will usually result in over 90% of trigger digits resolving after the steroid injection treatment. Steroid injections are safe and may be carried out by your family doctor or the radiologists or Mr Jarrett as the first line of treatment for trigger digits. Steroid injection treatment aims to provide a permanent resolution of the triggering. Steroid injections have a reduced chance of success if you have diabetes, or especially if you have had a carpal tunnel decompression in the past. There is a risk of infection with steroid injection and a very small risk of tendon rupture or skin discoloration or indentation.
Should the injections not work, a small operation called trigger release is available. Involving a small wound in the palm, this procedure is usually carried out under local anaesthetic, although general anaesthetic can be used if you prefer. The mouth of the sheath in which the flexor tendon travels is cut to prevent the triggering, and the condition resolves following this procedure.
Trigger Release Postoperative Care
A small bandage is worn for two days. Upon removal of the bandage the small sticky plaster is worn for a further 7 days, and then removed. I use absorbable sutures which do not require removal. The wound is usually tender for a few weeks, resolving over this period. From 10 days after your operation, you can commence washing your hand as normal, and I would recommend massaging the wound with moisturising lotion twice daily. The small white sutures will fall out by themselves over a few days and do not require formal removal by a nurse or doctor. We have a wound care video to help you on our website.
The fingers can be moved immediately following the procedure, but heavy work may not be possible until the wound has healed. The risks of the procedure are low but include infection (1%), stiffness and nerve injury (rare).