What is Stenosing Tenosynovitis?

By Cristiano Antonino Last updated Jun 19, 2023

Also known as trigger finger, stenosing tenosynovitis is a disease in which one of the fingers of the hand resists extension, finally yielding abruptly

The disease is known as trigger finger, because the movement of the finger resembles that of a trigger being pulled and then released.

Stenosing tenosynovitis: what is it?

Stenosing tenosynovitis is caused by narrowing of the synovial sheath around the tendon in the affected finger.

In the pathology one of the fingers remains flexed and suddenly extends with a snap.

The disorder is painful and, in the most serious cases, can cause functional blockage of the affected finger.

Trigger finger usually occurs in the dominant hand and most often affects the thumb, ring and middle fingers.

The most affected patients are those forced to perform repetitive gripping actions, for hobbies or occupational reasons.

Treatment depends on the duration of the disorder and its severity.

Symptoms of stenosing tenosynovitis

The symptoms of stenosing tenosynovitis can be severe or mild.

The most common are swelling and stiffness in the affected area, particularly in the morning.

Affected subjects feel a snapping sensation when they perform a flexion-extension movement or when they grab an object.

Among the symptoms we find the presence of a lump that appears at the base of the affected finger and localized pain in the palm of the hand.

In the most serious cases it is not possible to complete the extension gesture.

When the feeling of stiffness and jerk in the joint is severe, the area may feel warm and inflamed.

In this case, it is important to contact a doctor immediately as an infection may be present.

Stenosing tenovitis: causes

Stenosing tenosynovitis is caused by a narrowing of the sheath around the tendon in the affected finger.

The flexor tendons are anatomical structures that connect the muscle to the bone: they start from the forearm muscles, reach the wrist and the phalanges of the fingers.

The tendons have a protective membrane, the tenosynovia, which releases a lubricating fluid.

The latter allows the tendon to slide in the membrane without friction, while the finger performs flexion and extension movements.

When the tenosynovial sheath becomes inflamed and remains so for a long time, the space inside the tendon lining becomes narrowed.

In this case the flexor tendons do not slide through the sheath, blocking the finger which remains in the flexed position.

All this causes irritation and inflammation of the tendons. If the inflammation is prolonged, nodules, thickenings and scars may appear.

The synovial swelling prevents the tendon from passing the access of the digital canal.

In order to extend the finger, the patient is forced to perform a forced traction, causing the click associated with pain.

How is the diagnosis made?

The diagnosis of stenosing tenosynovitis is clinical.

The doctor can diagnose the disease by performing a brief physical examination.

During the visit, the patient is asked to open and close the hand to identify the painful areas and evaluate the fluidity of the movements with the transition from flexion to extension.

Palpation of the palm, particularly in the area of the metacarpophalangeal joint, allows the doctor to detect any lumps.