High risk and low prevalence diseases: Flexor tenosynovitis.

INTRODUCTION: Flexor tenosynovitis (FTS) is a deep space infection of an upper extremity digit which carries a high rate of morbidity.

OBJECTIVE: This review highlights the pearls and pitfalls of FTS, including presentation, diagnosis, and management in the emergency department (ED) based on current evidence.

DISCUSSION: FTS typically occurs after direct penetrating trauma to the volar aspect of an upper extremity digit. Development of a deep space infection that quickly propagates through the flexor tendon sheath of a digit can result in serious structural damage to the hand and place the patient at risk for significant morbidity such as finger amputation or even result in death. Signs of FTS include symmetrical swelling of the affected finger, the affected finger being held in a flexed position, pain on any attempt of passive finger extension, and tenderness along the course of flexor tendon sheath, known as the Kanavel signs. Systemic symptoms such as fevers and chills may occur. Recognition of these signs and symptoms is paramount in diagnosis of FTS, as laboratory and imaging assessment is not typically diagnostic. ED management involves intravenous antibiotics and emergent surgical specialist consultation.

CONCLUSION: An understanding of the presentation and risk factors for development of FTS can assist emergency clinicians in diagnosing and managing this disease in an expedited fashion.