[Cubital artery aneurysm and hypothenar hammer syndrome. Report of an unusual case].

Hypothenar hammer syndrome (HHS) is a rare condition and is a term used to described an aneurysm or thrombosis of the ulnar artery. It is considered an occupational or recreational injury and usually results of repetitive trauma to the hypothenar region, where th unique anatomy after the artery leaves the Guyon canal, allows the arterial injury. Clinical manifestations are more often unilateral, involving the dominant hand. However, some authors report the existence of a previous arteriopathy, predisposing to the injury, after repetitive palmar trauma.The authors report the clinical case of a 60 year-old woman, with an ulnar aneurysm in the non dominant hand, without evident existence of repetitive trauma. The pathological examination of the artery revealed muscular hyperplasia, without the characteristics of muscular fibrodysplasia. The authors believe that this case, once again, demonstrates the existence of an autonomous and "previous" arteriopathy associated to the traumatic lesion.