[Compression of the ulnar nerve at Guyon's canal caused by a pseudoaneurysm of the ulnar artery following trauma].

We repor there on a 16-year-old patient who presented with pain and swelling in the hypothenar eminence as well as loss of sensibility in the fingers of the region innervated by the ulnar nerve; this happened 2-3 weeks after an injury by a glass splinter in his proximal palm. A pseudoaneurysm could be verified by duplex sonography. The patient wished to avoid any graft for arterial bridging for religious reasons. On the basis of an the Allen test preoperatively and the intraoperative findings, an adequate blood supply of the finger by the radial artery was expected. Thus, in respect to the patients wish, the aneurysm was resected without bridging. The patient recovered perfectly. 4 years later, an MR-angiography showed the deep and superficial transverse palmar arc to be supplied by a voluminous radial artery. The ulnar finger arteries originated from the deep arc, the radial finger arteries from the superficial arc. In this paper, the criteria pro and contra grafting the ulnar atery at Guyons's canal will be discussed. © Georg Thieme Verlag KG Stuttgart · New York.