Results of Sympathectomy in the Upper Limb

THE sympathetic nerves have two main functions in the extremities. These are the control of the sweat glands and the regulation of blood-vessel calibre. Sympathetic nerve fibres reach the hand by passing down through the arm and forearm in the main somatic nerve trunks. At intervals along the course of these nerve trunks fibres are given off to supply the sweat glands of the region and the neighbouring blood vessels. These vasomotor fibres form plexuses on the surface of the blood vessels. A continuous stream of impulses passes down these fibres, so that normally there is a tonic constriction of blood-vessel walls. When the sympathetic coinnections to a part of the body are severed completely no sweating can take place and the blood vessels are no longer held in a state of constriction. The object of sympathectomy is, in the vast majority of cases, to prevent harmful narrowing of blood vessels, which, if allowed to continiue, would lead to impaired nutrition of the tissues and in the end to permanent damage. Only in a comparatively small number of-cases is sympathectomy performed for other disorders such as causalgia or hyperhidrosis. There have been three main phases in the evolution of operations for the sympathetic denervation of the hand. The first of these, mainly due to the work of Leriche,l was periarterial sympathectomy. This operation comprised stripping off the adventitia from a segment (usually one or two inches in length) of the main limb artery witlh consequent removal of this portion of the sympathetic plexus on its surface. In-this way it was hoped to interrupt the sympathetic supply to the limb blood vessels. This operation did not produce very impressive results, because aniatomically the sympathetic fibres to the hanid vessels leave the somatic nerve trunks at a point far distal to the segment of-the artery which was stripped. Tlhus this type of operation did not attack the relevant part of the sympathetic nervous system. The next form of sympathetic denervation was the cervico-dorsal ganiglionlec-tomy.2 In this operation the paravertebral ganiglionic chaini was exposed in the lower part of the neck, usually through an aInterior incision, anld the lower cervical and first dorsal ganglia removed. This operation gave excellenit early results, apart from the inevitable occurrence of a Horner's syn(lrome, but when these cases were reviewed months or years afterwards maniy were found to be relapsing and quite a few were as bad …