Treatment of trigger finger

Success rates are over 90%for percutaneous release while surgery Success rates vary from60-97 percent and higher complication in term of long term painfulscar inadequate release, nerve damage and flexor sheath infection.

 

Non-steroidal anti-inflammatory drugs
No evidence exists in the literature to suggest that non-steroidal anti-inflammatory drugs alone have any benefit other than temporary relief of pain in the palm.

 

Splintage
The aim of splintage is to reduce or remove tendon excursion through the A1 pulley for a long enough time to allow the synovitis around the pulley to resolve. Rodgers et al found that treating manual workers, who used repetitive hand movements, with splintage of the distal interphalangeal joint for six weeks resulted in resolution of symptoms in 53% of patients.¹⁷ Patel et al successfully treated 70% of digits by means of splintage of the metacarpophalangeal joint but were successful in treating only 50% of thumbs in this way.¹⁸ In both studies, those patients with more severe disease and longer duration of symptoms were less likely to benefit from splintage.

Steroid injection
The injection of steroid into the flexor sheath was advocated as a method of treatment in 1950. Success rates between 38% and 93% have been reported.^{7 9 14} Higher success rates are seen when injecting the thumb and in patients in whom a well defined nodule was palpable or whose symptoms had been present for less than six months. In patients in whom treatment fails or who have a recurrence of symptoms, a second steroid injection offers approximately half the efficacy of the first injection.^{9 14 w8}

No studies have shown that the steroid must be placed within the sheath to be effective; on the contrary, Taras et al showed that steroid injected into the subcutaneous tissue around the A1 pulley gave better clinical outcomes than that injected into the sheath alone.^w9 Injecting into the flexor sheath can prove difficult, as shown by Kamhin et al, who injected trigger fingers with dye and then went on to do an open A1 pulley release. They noted that only half of the injected fingers had dye within the sheath and that failure to introduce dye into the flexor sheath was higher in those patients with a longer duration of symptoms.¹⁹ Complications include dermal or subcutaneous atrophy, skin hypopigmentation, infection, and in one rare case tendon rupture.^w10

Percutaneous trigger finger release
Lorthioir first described percutaneous trigger finger release in 1958, and authors have since described its successful use in the outpatient department.²⁰ The technique involves placing the extended hand palm up with the metacarpophalangeal joints in a hyperextended position. The extended position facilitates access and ensures that the A2 pulley is held out to length and a maximal distance from the A1 pulley. The A1 pulley is stretched out and held stable in extension. The position also presents the pulley in a more superficial position, with the neurovascular bundles drawn medially and laterally away from the sheath. The tip of a 16/18 gauge needle is introduced through the skin on to the surface of the A1 pulley; the sharp tip of the needle is then used to incise the A1 pulley. Pope and Wolfe do not advise this method for release of a trigger index finger owing to proximity of the radial neurovascular bundle,²¹ and Bain et al apply the same rationale (proximity of the ulnar digital nerve) for not using this technique for the little finger.²² Cadaver studies, however, show that safe landmarks are available for percutaneous release for both little finger and index finger.^{15 16}

Success rates are over 90%.^{23 w11 w12} Complications are rare but include digital nerve injury, bowstringing (if release extends into the A2 pulley), infection, haematoma, and persistent pain.^{21-23 w11}

Surgery
Surgery is done under local anaesthetic in the operating theatre. The A1 pulley is exposed through a palmar skin incision, and the pulley is divided under direct vision. Success rates vary from 60% to 97%. Complication rates can be high; complications include long term scar tenderness, inadequate release, nerve damage, and flexor sheath infection.^{24 25}

 

Treatment in children
Children represent a distinct group of patients not only epidemiologically but also for treatment. The thumb is involved in 90% of cases. Treatment has traditionally entailed surgical release, but this has become increasingly controversial as authors have presented good results with non-operative methods of treatment.^{6 w13-w15}

Non-operative methods of treatment include physiotherapy administered by the parents with or without splintage. With physiotherapy alone, success rates of between 52% and 80% cure have been reported in patients whose thumb is not fixed in flexion or extension.^{w13 w14} With splintage, reports give success rates of 77-89%. In both groups, success rates seem to be higher in younger children and decrease with age.^{w14 w15}

Clinical review

Management and referral for trigger finger/thumb

Sohail Akhtar, clinical/research fellow¹, Mary J Bradley, research and postgraduate manager², David N Quinton, consultant hand surgeon², Frank D Burke, professor of hand surgery²

¹ 27 Belle Vue Avenue, Oakwood, Leeds LS8 2NN, ² Pulvertaft Hand Centre, Derbyshire Royal Infirmary, Derby

Correspondence to: S Akhtar [email protected]