A 42-year-old male with cold fingers. The condition started about 2 months ago and is steadily worsening.

What is your diagnosis?

Hypothenar hammer syndrome

The Angiography shows an occlusion of the ulnar artery and multiple embolic occlusions of the digital arteries. Sometimes there can also be an (occluded) aneurysm of the ulnar artery. This is the typical appearance of the Hypothenar hammer syndrome.

The Symptoms of hypothenar hammer syndrome include pain, pins and needles and loss of sensation in the affected hand. The fingers become sensitive to cold and they change colour.

EtiologyThe Hypothenar hammer syndrome is a condition of the hand in which the blood flow to the fingers is reduced. It occurs when workers repeatedly use the palm of the hand as a hammer to grind, push and twist objects. Those who use vibrating tools also seem to be at risk of acquiring the syndrome. The ulnar artery is most vulnerable in the distal portion of Guyon's canal where it is not protected by the palmaris brevis muscle. Guyon's canal is a depression between the pisiform and hook of hamate that is converted into a fibro-osseous tunnel by the piso-hamate ligament. The piso-hamate ligament and the volar carpal ligaments form the roof. The tunnel contains both the ulnar nerve and the ulnar artery and is a site for compression. Damage to the ulnar artery results in a reduction of blood flow and is the source of micro emboli to the fingers.

Treatment should focus on improving work practices and avoid using the palm of the hand as a hammer to pound, push or twist objects.

Literature

Kaji H, Honma H, Usui M, et al; Hypothenar hammer syndrome in workers occupationally exposed to vibrating tools.;J Hand Surg [Br]. 1993 Dec;18(6):761-6. [abstract]

Ferris BL, Taylor LM Jr, Oyama K, et al; Hypothenar hammer syndrome: proposed etiology.;J Vasc Surg. 2000 Jan;31(1 Pt 1):104-13. [abstract]

Husum B, Berthelsen P; Allen's test and systolic arterial pressure in the thumb.;Br J Anaesth. 1981 Jun;53(6):635-7. [abstract]

Drape JL, Feydy A, Guerini H, et al; Vascular lesions of the hand.;Eur J Radiol. 2005 Dec;56(3):331-43. [abstract]