EPITOMES-- and computed tomography may provide informa- sleeping. Symptoms are produced by an erect tion concerning the location of hematoma, ven- posture and are gradually relieved by sitting or tricular status and vascular injury. When obtunda- flexing the spine. Findings on neurological exami- tion, coma, or motor or other findings are the nation may be, and often are, normal, except for result of pressure effects secondary to hematoma, a nonspecific decrease or absence of ankle re- exploration in even profoundly unconscious pa- flexes, which is of little diagnostic value in older tients, in selected circumstances, may be reward- patients. Other reflex, motor or sensory findings ing. may be present only during activity. Except in GRANT E. GAUGER, MD those patients with coexistent serious vascular dis- REFERENCES ease, the are normal, and there are no Meirowsky AM: Penetrating wounds of the brain, In Meirowsky trophic changes. Lumbar spine x-rays may sug- AM (Ed): Neurological Surgery of Trauma. Washington, DC, Office of the Surgeon General, 1965 gest the presence of a narrow lumbar . Gonzalez CF, Grossman CB, Palacious E: Trauma, chap 7, In Gonzales CF (Ed): Computed Brain and Orbital Tomography. Arteriograms, when obtained because symptoms New York, John Wiley and Sons, 1976 are thought to be secondary to vascular disease, may show no abnormalities. In contrast, mye- lography shows severe or complete spinal block, and cerebrospinal fluid protein values often are Cauda Equina Syndrome increased. Usually lumbar puncture is diffiCult in ARTERIAL INSUFFICIENCY secondary to severe such patients and proper positioning of the needle vascular disease is an established cause of inter- may require fluoroscopic control and cisternal mittent limping, which is the meaning of the term puncture may be necessary. "claudication." In recent years postural and is- When the patient's symptoms are the result of a chemic neurogenic claudication mechanisms which narrow spinal canal producing cauda equina com- lead to pain, sensory changes and weakness in pression, wide throughout the ste- some patients with a narrow lumbar spinal canal notic areas will very often be followed by com- have been described. This neurogenic intermittent plete relief of symptoms and return to normal, claudication syndrome usually occurs in older unrestricted activity. Pronounced improvement men, and is characterized in part by the onset, frequently has been noted even in cases with pro- with exercise, of a specific pattern of numbness, found preoperative symptomatic disability. tingling or dyesthetic sensation in buttocks and GRANT E. GAUGER, MD lower extremities, accompanied, if exercise con- REFERENCES Wilson CB, Ehni G, Grolimus JM: Neurogenic intermittent tinues, by weakness which may prevent further claudication, In Tindall G (Ed): Clinical Neurosurgery, Vol 18. walking. Pain is not invariable. Frequently, the Baltimore, Williams & Williams Co., 1971, pp 62-85 Wilson CB: Significance of the small lumbar spinal canal: patient chooses to maintain a position of flexion of Cauda equina compression syndromes due to -Part III. Intermittent claudication. J Neurosurgery 31:499-506, Nov the lumbar spine during standing, walking or 1969

ADVISORY PANEL TO THE SECTION ON NEUROSURGERY

BYRON C. PEVEHOUSE, MD, Chairman, San Francisco, CMA Scientific Board

GRANT GAUGER, MD GEORGE AUSTIN, MD JOHN F. ALKSNE, MD CMA Section on Neurosurgery Loma Linda University University of California, San Diego Chairman Oakland JOHN HANBERY MD Stanford University CHARLES B. WILSON, MD JOHN A. MCRAE, MD University of California, San Francisco CMA Section on Neurosurgery JULIAN YOUMANS, MD Secretary University of California, Davis THIEODORE KURZE, MD Los Angeles University of Southern California ELDON FOLTZ, MD Los Angeles LAURENCE PIrrs, MD University of California, Irvine CMA Section on Neurosurgery Assistant Secretary W. EUGENE STERN, MD PHILIPP LIPPE, MD San Francisco University of California, Los Angeles San Jose

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