Trigger finger release: Open and percutaneous

Surgical release reliably relieves the problem of trigger finger for most patients: approximately 97% of patients have complete resolution after operative treatment. Persistence of triggering is more common than recurrence. Trigger release should be done with a local block so that the cessation of triggering of a particular finger can be evaluated. Some adjacent finger triggering may become obvious only after a given finger is released; both can be released at the same surgical setting. The safety and effectiveness of percutaneous trigger finger release using a needle, or a push knife are documented. Incomplete pulley release and damage to the flexor tendons and digital nerves, especially in the index finger and thumb, remain of some concern with this technique.

Open release of trigger finger

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Local anesthetic infiltration in the palm proximal to the incision site is preferred ( Fig. 43.1 ). The use of a pneumatic arm tourniquet may be helpful, although a high forearm Esmarch wrap is usually sufficient.
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Make a transverse incision about 2 cm long, several millimeters distal to the distal palmar crease for middle, ring, and small trigger finger releases, and several millimeters distal to the proximal palmar crease for index trigger finger releases. Trigger thumb releases can be done through incisions either distal or proximal to the metacarpophalangeal joint flexion crease. Alternative incisions for the fingers can be made obliquely or longitudinally between the metacarpophalangeal and distal palmar creases and obliquely across the thumb metacarpophalangeal flexion crease ( Fig. 43.2 ).
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Avoid the digital nerves, which on the thumb are more palmar and closer to the flexor sheath than might be anticipated. The thumb radial digital nerve is especially vulnerable.
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Identify with a small probe the discrete proximal edge of the first annular pulley of the flexor sheath.
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Place a small knife blade or one blade of a pair of slightly opened blunt scissors just under the edge of the sheath and gently push it distally, cutting the first annular pulley. Avoid cutting too far distally and disrupting the oblique pulley. Incise the sheath from proximal to distal, approximately 1 cm, and reassess for triggering. If the finger triggers when the patient actively flexes and extends the digit, either the A1 and palmar pulleys are incompletely released, or an alternate site of triggering is present. The distinction between the A1 and A2 pulleys may not be apparent; however, when the distal A1 pulley edge is released, the divided pulley leaves are parallel rather than ending in a V-shaped pattern ( Fig. 43.3 ).
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Evaluate the distal end of the palmar fascia and the proximal flexor tenosynovium to release all structures proximally that might bind on the tendon. Ensure that all neurovascular structures are retracted out of the way and that all structures to be incised are seen.
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After the tendon sheath has been released, encourage the patient actively to flex and extend the digit to ensure that the release is complete.
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Close the skin and apply a small, dry compression dressing.