Hypothenar hammer syndrome: an update with algorithms for diagnosis and treatment.

Hypothenar hammer syndrome is an uncommon cause of symptomatic ischemia of the hand secondary to the formation of aneurysm or thrombosis of the ulnar artery as a result of repetitive trauma to the hypothenar region. The injury to the palmar ulnar artery occurs in subjects who use the hypothenar part of the hand as a hammer; the hook of the hamate strikes the superficial palmar branch of the ulnar artery in the Guyon space. Such injuries of the ulnar artery may lead to severe vascular insufficiency in the hand with thrombosis and distal embolization of the digital arteries. Imaging of vascular lesions of the hand has greatly improved in recent years with the use of Doppler, multislice computed tomographic angiography, magnetic resonance imaging, magnetic resonance angiography, and digital subtraction angiography. The aim of this article is to describe a case report using current-day imaging and to present a review of literature. Algorithms for the diagnosis and treatment of hypothenar hammer syndrome will be proposed.