Tenosynovitis is the inflammation of the tendon and its sheath. It mostly occurs in the hand but can affect any tendon in the body. Most cases are on the flexor side tendons. These may be due to infection or from other chronic diseases.
The cardinal feature of flexor tenosynovitis is pain along the tendon sheath, with associated swelling around the joint adjacent. The finger is usually flexed slightly and there is pain on passive movement along the tendon.
In infectious tenosynovitis there may be associated fever. In gonococcal tenosynovitis, not associated penile or vaginal discharge occurs and the wrist, hand and sometimes the ankle are the most common sites. In traumatic cases the site of inoculation may be overtly infected, but many times there is no obvious wound .
Plain radiographs should be done to rule out bone involvement. Magnetic resonance imaging (MRI) is an accurate modality for diagnosis.
Usually the treatment includes surgery and antibiotics. For stage 1, irrigation and drainage are necessary. Stage 2 or 3 may be treated with surgical debridement and irrigation, amputation if necessary. Depending on the results of fluid and gram stain, antibiotics should be started promptly, a drug that covers Staphylococcus aureus and streptococci will be advisable; this includes ciprofloxacin or a third generation cephalosporin. Vancomycin may be used if a methicillin-resistant species is suspected.
The inflammatory causes respond to anti-inflammatory drugs such as non-steroidal anti-inflammatory drugs (NSAIDs) and steroids, but an infectious etiology must be ruled out. The involved joint should be immobilised   .
Infectious causes who present early and get treatment, will have an excellent outcome. Those who have chronic infection and disseminated disease will have a poorer outcome. Poor outcomes include loss of range of movement and tendon rupture. Other comorbidities such as a decreased immunity or diabetes are a poor prognostic markers, and tend to have multiple tendons and joints involved.
Most of the time the cause is not known, but the etiology may be divided into infectious and non-infectious.
There is very little data on the incidence of this condition, but it has been noted that up to one third of the patients are diabetic. Gonococcal tenosynovitis is usually common in the young sexually active individuals. Also this condition is very common in rheumatoid arthritis sufferers .
The infection occurs by various mechanisms: Trauma with inoculation into the tendon, contagious spread from infected adjacent soft tissues, and through the blood stream. Most infections will occur acutely after inoculation except for a few organisms such as mycobacterium which may have a subacute presentation. Usually animal bites and lacerations are associated with polymicrobial infections including gram negative bacteria. Different forms of trauma have associated bacteria, such as puncture wounds form thorns and trees may result in fungal infections, while animal bites may give rise to polymicrobial infections with Pasteurella multocida and others . Infections to tendon from other sites via hematogenous spread, is common for Mycobacterium and Nesseria gonorrhoeae.
The infections usually progresses in stages:
This occurs due to a different mechanism. There is fibrous proliferation, until there is impingement and constriction of movement.
Prompt treatment of the underlying cause is the best mode to avoid complications. Since most cases of infectious causes are related to trauma, necessary protective gear and equipment should be used at potentially dangerous sites. For gonococcal infections, protected intercourse is the best prevention.
The most common sites for tenosynovitis are the shoulder, the tendon of the long head of the biceps, popliteus tendon, Achilles tendon and the abductor pollicis longus. It is thought that continuous microtears and degenerative changes are the most common cause of the condition.