Ultrasound Use and Outpatient Management for Pyogenic Flexor Tenosynovitis: A Case Report.

Pyogenic flexor tenosynovitis (PFT) is an orthopedic emergency that necessitates prompt diagnosis and treatment. Unfortunately, the diagnosis is largely clinically based on Kanavel's four cardinal signs with all four symptoms being present approximately 22% to 56% of the time. Evidence suggests that PFT diagnosed within 48 h of onset does not need surgical intervention. Ultrasonography can be used to aid in the diagnosis of PFT. It has a sensitivity of 94.4% and a negative predictive value of 96.7%. This illustrative case report demonstrates ultrasound's utility to not only aid in diagnosis but also serve as a tool for monitoring patient response.