The Application Value Of Somatosensory Evoked Potentials And The Area Ratio Of Cervical Spinal Cord To Vertebral Canal Effective Area In Assessing Curative Effect Of Cervical Spondylotic Myelopathy

Objective: To investigate the value of somatosensory evoked potentials and the ratio ofcervical spinal cord to vertebral canal effective area in assessing curative effect ofcervical spondylotic myelopathy with case-control study method.Method:60patients with confirmed cervical spondylotic myelopathy(CSM) tookcervical vertebra MRI and SEP test, and were graded by JOA after admission to hospital.Cervical spinal canal area and cervical spinal cord area of C5/6were measured in MRIworkstation. The area ratio of cervical spinal cord to effective spinal canal werecalculated. According to the mean ratio of each index from all cases，the patients weredivided into two groups: higher-ratio group (40example) and lower-ratio group(20example). According to the result of SEP, the patients were divided into two groups:normal group (32example) and abnormal group (28example). Four types were classifiedaccording to SEP and MRI. Type A: N/H24patients, Type B:A/H16patients, TypeC:N/L8patients, Type D:A/L12patients.Supply conventional conservative therapyfor all patients, including drug、traction、manipulation and so on, the therapeutic effectwere also graded according to the JOA scoring system. Then, the data were analyzedand summarized via SPSS13.0statistical software to research the correlation of thefactors. Results:①The comparison of JOA scores in the area ratio of cervical spinal cord toeffective spinal canal high and low ratio groups: there was no significant difference intwo groups before treatment(P>0.05), but there was significant difference in two groupsafter treatment(P<0.05).②The comparison of rate of clinical improvement in the arearatio of cervical spinal cord to effective spinal canal high and low ratio groups: therewas no significant difference in two groups (P>0.05).③The comparison of JOA scoresin SEP normal and abnormal groups: there was no significant difference in two groupsbefore treatment(P>0.05), but there was significant difference in two groups aftertreatment(P<0.05).④The comparison of rate of clinical improvement in SEP normaland abnormal groups: there was significant difference in two groups(P<0.05).⑤Thecomparison of the area ratio of cervical spinal cord to effective spinal canal in SEPnormal and abnormal groups: there was no significant difference in two groups (P>0.05).⑥The comparison of JOA scores in SEP combine to the area ratio of cervical spinalcord to effective spinal canal in A、B、C、D group: there was no significant differencein two groups before treatment(P>0.05), but there was significant difference in twogroups after treatment(P<0.001).⑦The comparison of rate of clinical improvement inSEP combine to the area ratio of cervical spinal cord to effective spinal canal in A、B、C、D group: there was significant difference between types and the therapeutic effect(Hc=28.045,P<0.001). Among them the best therapeutic effect was group A and theworst was group B.Conclusions:①The area ratio of cervical spinal cord to effective spinal canalcombine with SEP can be quantitatively reflect the severity of the CSM, there wassignificant difference between types and the therapeutic effect.②The area ratio ofcervical spinal cord to effective spinal canal combine with SEP was better than MRImeasurement or SEP detection which contribute to assess more accurately oftherapeutic effect and diagnose CSM.