Changing patterns of septic tenosynovitis of the distal extremities.

The medical literature reports that human pyogenic tenosynovitis occurs almost exclusively in flexor tendons of distal extremities with only rare case reports in extensor compartments. We report a series of patients with septic extensor compartment tenosynovitis of the extremity. Twenty cases of septic tenosynovitis tendons of the wrist, hands, feet, and ankles were presented to our emergency department over a 4.17-year period, 15 men (one, twice over a 2.5-year span) and 4 women with an average age of 39 years. Diagnosis was made using CT (n = 6), MRI (n = 14), and in one case ultrasound (US). All cases were confirmed surgically. During the data collection period, no case of flexor septic tenosynovitis were presented. All patients were intravenous drug users. All imaging modalities showed fluid within the infected tendon sheaths and evidence of enhancement after contrast administration where contrast was administered. The single US showed hypervascularity on Doppler imaging. All wrist and hand infections (n = 15) occurred in the non-dominant hand, and all cases involved the fourth and next most commonly (n = 9 each) in the second and third extensor compartments. In the ankle and foot (n = 5), the extensor digitorum longus tendon was most commonly infected. Twelve patients (60 %) had soft tissue abscesses adjacent to infected tendon sheaths. The most common organism cultured from the tendon sheaths was Staphylococcus aureus, methicillin sensitive and resistant and often admixed with other flora. Common use of intravenous drugs now makes extensor septic tenosynovitis an important clinical diagnosis and likely now more common than flexor septic tenosynovitis.