Transdiscal lumbar sympathetic block: a new technique for a chemical sympathectomy.

UNLABELLED: Genitofemoral neuritis, which occurs when the neurolytic solution spreads into the psoas muscle, is the most common complication after neurolytic lumbar sympathetic block. We developed a transdiscal approach for neurolytic lumbar sympathetic block to reduce the danger of genitofemoral neuritis by making a sympathectomy without penetration of the psoas muscle, through which the genitofemoral nerve passes. We attempted transdiscal lumbar sympathetic block in 14 patients for whom the last previous lumbar sympathetic block performed by using the conventional paravertebral method was unsuccessful. Under fluoroscopic guidance, the needle was inserted transdiscally at L2-3 and/or L3-4 and was advanced until its tip pierced the anterior longitudinal ligament. Radiography and computed tomography revealed that the injected contrast media spread along the anterolateral surface of the vertebral column without any flow into the psoas muscle. Alcohol was injected successfully in all patients. During the 1-mo follow-up period, no patients had any symptom of genitofemoral neuritis. Thirteen patients who had been suffering from lower extremity pain achieved partial or complete pain relief. One patient with plantar hyperhidrosis achieved persistent anhidrosis. These results suggest that the transdiscal approach can be a technical option for neurolytic lumbar sympathetic block. IMPLICATIONS: Neurolytic lumbar sympathetic block was performed with the needle advanced through the intervertebral disc. With this technique, the risk of genitofemoral neuritis, the most common complication after neurolytic lumbar sympathetic block, was reduced because the needle does not penetrate the psoas muscle, through which the genitofemoral nerve passes.