Trigger Finger / Stenosing Tenosynovitis

Cause

Trigger finger, also known as stenosing tenosynovitis, is one of the most common diseases of the hand. Five annular ligaments along the flexor side of the fingers affix the tendons to the bones, forming a sheath through which the tendons pass. This enables end-to-end flexion in all finger sections.

If one of these annular ligaments - the ligament closest to the body, the A1 pulley, is often affected - or the flexor tendon thicken, the natural gliding movement is limited.

The cause is usually mechanical overexertion, which irritates the annular ligament or the tendon sheath. Women are more commonly affected than men. 

Symptoms

The most noticeable symptom is a snapping phenomenon, where the tendon can only be moved by a jerking movement of the annular ligament. The patient often feels like the finger “gets stuck” and is only able to stretch or bend it with great difficulty or by using the other hand. Overstimulation can cause swelling or pain in the affected area. Symptoms are often worse in the morning after waking up and then improve over the course of the day.

Diagnosis

The condition is mainly diagnosed clinically. A ganglion of the annular ligament can be identified using high resolution ultrasound and the tendon can also be examined dynamically, i.e. while it is being moved. An X-ray examination to rule out any bony deformities can also be helpful.

Treatment

Ending the mechanical stress factor occasionally leads to improvement.

Movement therapy (e.g., occupational therapy or physiotherapy) and treatment with medication (e.g., massaging with Voltadol forte cream daily) aim to reduce the swelling of the tendon sheath.

Infiltration therapy can help reduce local swelling and thus restore the gliding facility of the tendons.

Minimally invasive surgery:

If none of the above measures lead to improvement or if the condition has already existed for an extended period of time, surgical therapy is indicated. In this case, the ligament is split while under ice, using a minimally invasive procedure that allows the tendon to glide again.

Aftercare

The surgery is an outpatient procedure and generally does not require an overnight stay in the hospital.

NSAIDs (non-steroidal anti-inflammatory drugs) should be taken for three days.

The wound must be kept clean and dry until healed, about 10–14 days. No heavy lifting or physical labor should be done during this time.

In order to regain optimum functionality, occupational therapy and targeted exercises should be started as soon as possible following the operation. 

A supportive splint may be indicated if swelling and increased scarring are observed.

Overall, the chances of success are very high and hand function is usually restored quickly.