Lumbar Sympathectomy by Laser Technique

Abstract

Two common syndromes in which sympathetic pain appears to be the cause are causalgia and reflex sympathetic dystrophy. In the past, permanent interruption of the lumbar sympathetic chain has been accomplished by open surgery or phenol or alcohol injection. Subsequently, percutaneous lumbar sympathectomy by radiofrequency lesions involved less morbidity. The Holmium: YAG laser has now been found to be even more effective and longer lasting than the radiofrequency technique. An increasing number of patients are seeking medical treatment for pain associated with sympathetic nervous system. Two common syndromes in which sympathetic pain appears to be the cause are causalgia and reflex sympathetic dystrophy. True causalgia follows partial injury to a major nerve trunk such as the sciatic nerve or its large branches. Reflex sympathetic dystrophy may occur following minor trauma to the neural structures that accompany fractures, soft-tissue injuries, and surgical incisions. Clinical characteristics include burning, poorly localized dermatomal distribution of stabbing pain, hyperesthesia, vasomotor alterations leading to trophic changes, changes in skin temperature, alteration of sweating patterns, piloerection, and swelling. Other conditions complicated by sympathetic dysfunction are amputation stump pain, circulatory insufficiency in the legs, arteriosclerotic disease of the lower limbs, intermittent claudication, and arterial embolism. Following endoscopic or percutaneous discectomy, some patients experience a burning pain with skin trophic changes and allodynia due to irritation of the sympathetic nervous system during manipulation of surrounding structures. This procedure, performed in patients who present with symptoms of causalgia following discectomy is highly effective in relieving this type of pain. METHODS AND MATERIALS Anatomically, the lumbar sympathetic chain lies at the anterolateral border of the vertebral bodies (fig 1). The aorta is positioned anteriorly and slightly medial to the chain on the left side. The inferior vena cava is more closely approximated to the chain on the right in an anterior plane. Many other small lumbar arteries and veins are positioned near the sympathetic chain. The psoas muscle is situated posteriorly. Blockade of the sympathetic nerves can also be performed with spinal, epidural or peripheral nerve blocks, but relief of pain after lumbar sympathetic block will definitely confirm the painful etiology as sympathetically mediated. Most fibers headed for the lower extremity pass through the second and third lumbar ganglia, so that a sympathetic block placed at the L4 level provides almost complete sympathetic denervation to the lower extremity. The pain relief obtained is usually immediate and can be long-lasting, outlasting the duration of action of the local anesthetic. If the pain relief is transient, then sympathetic denervation can be performed with laser. Lumbar Sympathectomy by Laser Technique