Pyogenic Flexor Tenosynovitis by Point-of-care Ultrasound in the Emergency Department

INTRODUCTION: Pyogenic flexor tenosynovitis (PFT) is difficult to diagnose on clinical grounds alone as many patients requiring an operation do not have all four of Kanavel’s signs. Previous studies have shown that hypoechoic fluid surrounding the flexor tendon on ultrasound is associated with this diagnosis. We sought to determine if emergency physicians (EPs) could recognize this finding in patients with suspected flexor tenosynovitis using point-of-care ultrasound (POCUS). METHODS: We present a retrospective case series of seven patients suspected of PFT who had hypoechoic fluid surrounding the tendon on POCUS performed by the treating EP. We report on the patient characteristics, history of trauma by puncture wound, number of Kanavel’s signs, treatment course, and operative findings. RESULTS: We identified seven patients suspected to have flexor tenosynovitis by the emergency department attending physician who had anechoic or hypoechoic fluid surrounding the flexor tendon on real-time POCUS examination. Patients ranged in age from 16 – 51 years. All were male. All patients had at least two of Kanavel’s signs on examination. Five of seven (71%) patients had history of recent trauma to the affected hand. Four of seven (57%) were managed in the operating room. One of seven (14%) had incision and drainage at the bedside, and the remaining two (28%) were managed non-operatively and successfully with antibiotics alone. CONCLUSION: Our study demonstrates that EPs can recognize the finding of hypoechoic or anechoic fluid surrounding the flexor tendon on POCUS.