STRAIGHT LEG RAISING TEST AND LUMBAR CEREBROSPINAL-FLUID LEVELS OF VASOACTIVE INTESTINAL POLYPEPTIDE AND SOMATOSTATIN IN PATIENTS WITH LOW-BACK-PAIN

Study Design. Straight leg raising was recorded before myelography in 77 patients. At myelography, samples of cerebrospinal fluid were drawn and later analyzed for neuropeptides vasoactive intestinal polypeptid e and somatostatin. Objectives. The study sought to examine correlatio ns, if any, between a positive straight leg raising test and cerebrosp inal fluid neuropeptide levels. Methods. The straight leg raising test was recorded for all patients before a myelography examination was pe rformed because of intractable leg pain symptoms. Forty-seven of the p atients were men and 30 were women. Cerebrospinal fluid samples were o btained from all patients upon myelography. Levels of the neuropeptide s vasoactive intestinal polypeptide and somatostatin were analyzed in a blind manner by radioimmunoassay, using commercially available radio immunoassay kits. Results. The results are compatible with previous ob servations that suggest cerebrospinal neuropeptide levels are altered in conjunction with neural injury or pain syndromes. In the present mi xed back pain patient population, which included radicular pain sympto ms due to disc herniation and lumbar stenosis, alterations in vasoacti ve intestinal peptide levels in particular were observed with a positi ve straight leg raising test. Conclusions. Nerve root injury, as sugge sted by a positive straight leg raising test, appears to be neurochemi cally linked to altered cerebrospinal fluid vasoactive intestinal pept ide levels.