Tenosynovitis, also known as tendovaginitis, is a compression of the tendon sheath affecting its mechanics, which can cause sheath inflammation or trigger finger tendovaginitis stenosans. These types of stenoses can also relate to other hand pathologies such as carpal tunnel syndrome, tennis elbow (epicondylitis humeri radialis) etc.
The flexor tendons of the hand run along the fingers through narrow canals lined with soft tissue (osteofibrous canals) which are strengthened at certain points by the cruciform and annular pulleys. On the extensor side of the hand, the extensor retinaculum acts as a similar canal for the extensor tendons. These tendon canals are predestined to develop bottlenecks. Any disparity between the diameter of the tendon sheath and the circumference of the tendon can cause narrowing (stenosis) which affects the sliding of the tendon during flexion or extension of the fingers.
A patient experiences tendon sheath inflammation or stenosis as painful swelling with movement-induced pain, often accompanied by a rubbing or cracking in the tendon compartment (sometimes referred to as snapping finger). The two most common hand pathologies are trigger finger, also known as trigger thumb (tendovaginitis stenosans), or the compression of the first extensor tendon compartment in the wrist (as known as de Quervainˈs syndrome).
Diagnosis and Examination
Patients report A1 annular pulley pain, often in combination with a painful snapping of the fingers or thumb. The finger or thumb “snaps” into place during flexion; when extending with resistance the patient usually feels severe pain in the region of the annular pulleys. The palpation of the affected finger almost always results in pain upon the application of pressure and a nodule at the A1 annular pulley. Ultrasound images in particular are very helpful in identifying swollen seams around the flexor tendons and a thickening of the annular pulley, both of which indicate inflammation.
Initially, a non-operative therapeutic approach can be attempted using the injection of a cortisone/local anaesthetic mix in the A1 annular pulley region. Symptoms can then sometimes subside for a few weeks or even months. For patients who do not wish to undergo an injection-based treatment, a splint can be fitted by a hand therapist, coupled with resting the hand for a few weeks. However, the results of these treatments vary greatly.
It is common for the symptoms to return after conservative treatment, making annular pulley release the most commonly applied surgical technique in these cases. Both minimally invasive and open techniques are possible. For most hand surgeons, the open A1 annular pulley release has proven to be the most successful, and this is also the case for the practice founder, Prof. Sauerbier.
The operation is usually carried out on an outpatient basis with local (wide-awake), plexus, and general anaesthesia options available. The hand surgeon, aided by specialist surgical magnifying spectacles, makes an incision in the A1 annular pulley of the affected finger or thumb and, using careful dissection, ensures that the blood vessels and nerve of the finger are intact. The A1 annular pulley is severed after reaching the flexor tendon sheath. After the unobstructed sliding of the flexor tendon is confirmed, the surgeon closes the wound.
Following the operation, a loose bandage is applied leaving the fingers or thumb exposed. The suture material is removed after 12 to 14 days. We recommend beginning with finger movement exercises immediately under the supervision of a hand therapist. Normal use of the hand should be possible after 3 to 5 weeks. Generally, complete restoration of range and movement and strength can be expected.