Vascular Quadrilateral Space Syndrome in 3 Overhead Throwing Athletes: An Underdiagnosed Cause of Digital Ischemia.

Vascular quadrilateral space syndrome (vQSS) is an underdiagnosed cause of extremity ischemia, pain, and paresthesia in overhand throwing athletes. The mechanism of vQSS is thought to result from repeated abduction and external rotation of the arm leading to a distraction injury of the posterior circumflex humoral artery (PCHA) as this courses through the quadrilateral space. This trauma may cause dissection and dissecting aneurysm formation. Thrombus from this arterial injury then embolizes down the arm resulting in the symptomatic presentation. Patients were often presented after multiple embolic events, which have resulted in obliteration of digital arteries. Later stages of presentation may include ischemic ulceration and gangrene. We report 3 cases of vQSS in overhand throwing athletes. All 3 underwent surgical correction and have returned to competition. We discuss presentation, diagnosis, imaging findings, management, outcomes, and review of the literature. Prompt recognition of this syndrome is essential to optimal treatment, which includes PCHA ligation and division with or without thrombolytic therapy. Increased awareness of vQSS is needed among coaches and athletic trainers who often identify the symptoms and initiate the treatment. When treated promptly, these athletes return to baseline functional status.