title: Comparison of surgical and electrodiagnostic findings in single root lumbosacral radiculopathies.
abstract: To identify the segmental innervation of L-2-S-1 muscles, we compared the preoperative electrodiagnostic examinations of 45 patients with single-level lumbosacral radiculopathies confirmed radiologically and surgically. The electrodiagnostic findings were classified as abnormal only by the needle examination and only if muscles demonstrated active denervation or a marked neurogenic motor unit potential firing pattern. In comparison to other surgical, intraoperative root stimulation, and clinical studies, we found several differences. Overall, there was little overlap among L-2-4, L-5, and S-1 radiculopathies. The tibialis anterior was predominantly L-5 innervated, the gastrocnemius (medial and lateral head) predominantly S-1 innervated, and the biceps femoris (short and long head) exclusively S-1 innervated. The two heads of biceps femoris were not affected in any patients with L-5 radiculopathy in whom they were examined. These findings help guide both the clinician and surgeon in the diagnosis and treatment of lumbosacral radiculopathies.
authors.affiliation: Department of Neurology, S-90, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, Ohio 44195, USA.
authors.forename: Bryan E
authors.initials: BE
authors.lastname: Tsao
authors.forename: Kerry H
authors.initials: KH
authors.lastname: Levin
authors.forename: Russ A
authors.initials: RA
authors.lastname: Bodner
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004576:Electromyography; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae; D008161:Lumbosacral Region / Q000294:innervation; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000294:innervation; D011843:Radiculopathy / Q000175:diagnosis* / Q000601:surgery*