title: [The diagnostic value of SEP in LDH and its forensic significance].
abstract: OBJECTIVE
  To evaluate the diagnostic value of somatosensory evoked potential(SEP) in lumbosacral disc herniation(LDH).
  
  
  METHODS
  Posterior tibial nerve somatosensory evoked potential(PTNSEP) and dermatomal somatosensory evoked potential (DSEP) were recorded from 60 patients with radiculopathy caused by LDH and 30 healthy subjects.
  
  
  RESULTS
  DSEP was abnormal in 56 cases (93.3%) and PTNSEP was abnormal in 26 cases (43.3%). The significant difference was observed (P<0.001). The abnormality of DSEP from L4 dermatome was detected mainly in patients with L3-4 LDH, the abnormality of DSEP from L5 dermatome was detected mainly in patients with L4-5 LDH, the abnormality of DSEP from L5S1 dermatome was detected mainly in patients with S1 LDH. DSEP can reflect the compressed extent of nerve root.
  
  
  CONCLUSIONS
  There was a good correlation of DSEP with lumbosacral nerve root injury,which supplement the information that can not be provided by imaging examingation. DSEP is a sensitive electrophysic method that not only is used to evaluate single nerve root function, but also is helpful in the location of the lesion.
authors.affiliation: Department of Forensic Medicine, China Medical University, Shenyang 110001, China. xxmzhj@163.com
authors.forename: Xiao-ming
authors.initials: XM
authors.lastname: Xu
authors.forename: Xing-ben
authors.initials: XB
authors.lastname: Liu
authors.forename: Chuan-fei
authors.initials: CF
authors.lastname: Zheng
mesh_terms: D000328:Adult; D004558:Electric Stimulation; D004568:Electrodiagnosis / Q000379:methods; D005073:Evoked Potentials, Somatosensory; D005260:Female; D005554:Forensic Medicine; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000175:diagnosis* / Q000503:physiopathology; D008159:Lumbar Vertebrae; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013126:Spinal Nerve Roots / Q000473:pathology* / Q000503:physiopathology; D013979:Tibial Nerve / Q000502:physiology