Nodular tenosynovitis of a finger is the most common pathology of the hand after carpal tunnel syndrome. Symptomatology can range from a simple painful discomfort in the palm of the hand during flexion and extension movements of a finger, to a painful blocking of the finger in flexion, sometimes irreducible.
In order to understand the origin of the finger, it is necessary to know the anatomical layout of the flexor tendons in the fingers and the hand. These tendons follow the muscular body located in the forearm. They run across the palm and end at the tips of the fingers. When the fingers are flexed, the flexor tendons do not catch the string thanks to a system of reflection pulleys "that press them against the phalanges". To disturb the functioning of the tendon-pulley system, a simple thickening of the tendon (called tenosynovitis) is enough to cause a difficulty of sliding of the tendon which can go until the blocking of this one in the pulley. This is what happens when a finger jerk occurs: it is a chronic inflammation that establishes a vicious circle: the rubbing of the tendon aggravates the inflammation, which thickens the tendon, thus increasing the rubbing. A nodule is created on the tendon path which will block the sliding of the tendon in the pulley, causing a painful blocking in flexion of the finger.
The chronic inflammation necessary for the development of a protruding finger can be caused by:
- a repetitive or intensive manual movement
- an infection of a finger
- a history of wounding in the area of the tendon-pulley system
- an inflammatory disease (rheumatoid arthritis)
- more rarely, the protruding finger may be congenital, with a predominance of damage on the thumb.
Typical warning signs
The first sign of a sticking finger is often a pain located at the base of the finger on the palm side (palmar side). Applying pressure to this area can trigger or accentuate this pain. It is located in the area of conflict between the tendon and the pulley, the area where the inflammation and the nodule will settle.
If anti-inflammatory treatments are ineffective or if there is a painful blockage when the finger is flexed, surgery will have to be performed under loco-regional anaesthesia, on an outpatient basis. It consists in removing the nodule and the peri-tendinous inflammation. It is performed by a mini-invasive surgery (mini-incision) which allows immediate reuse of the operated finger after the operation. The disappearance of the blockage is also immediate. A few re-education sessions are performed to allow for an even faster recovery. In most cases, recovery is complete in about three weeks. There is usually no post-operative pain. Complications are rare.