Objective:To analyze the correlation between the amplitude changes of motor evoked potential(MEP),the 3D volume changes of spinal canal measuring by postoperative CT and the improvement rate of clinical symptoms after...Objective:To analyze the correlation between the amplitude changes of motor evoked potential(MEP),the 3D volume changes of spinal canal measuring by postoperative CT and the improvement rate of clinical symptoms after the spinal canal decompression in minimally invasive transforaminal lumbar interbody fusion(MIS-TLIF),and to explore the predictive value of the changes of both MEP amplitude and spinal canal volume in the assessment of long-term clinical prognosis in MIS-TLIF.Methods:A retrospective study of 68 patients with L4/5 spinal stenosis treated with MIS-TLIF was performed.The changes of both intraoperative MEP amplitude and 3D spinal canal volume during the spinal canal decompression,as well as the visual analogue scale(VAS)and Oswestry dysfunction index(ODI)scores in the long-term follow-up were all recorded.Results:The values of intraoperative MEP amplitude was 159.04%higher in 68 patients with MIS-TLIF after spinal canal decompression(P<0.01).The 3 postoperative 3D spinal canal volume(4.89±1.27)cm increased by 31.22%in comparison 3 with preoperative date(3.78±1.08)cm(P<0.01).The VAS and ODI scores were improved to 78.55%and 80.60%,respectively at the last follow-up(P<0.01).The improvement rate of MEP amplitude on the decompression side was positively correlated with the improvement rate of postoperative spinal canal volume(r=0.272,P=0.025).The improvement rate of postoperative spinal canal volume was positively correlated with the improvement rate of VAS and ODI at the last follow-up(r=0.656,r=0.490,P<0.01).Moreover,the improvement rate of MEP amplitude on the decompression side was also positively correlated with the improvement rate of VAS and ODI at the last follow-up(r=0.322 and 0.235,respectively,P<0.05).Conclusion:The increase of MEP amplitude after spinal canal decompression in patients with lumbar spinal stenosis treated by MIS-TLIF was closely correlated with both of the increase of spinal canal volume and the improvement of clinical symptoms.Therefore,MEP amplitude monitoring was not only the one of the important monitoring methods for predicting the prognosis of MIS-TLIF but also the reliably predictive value in the long-term clinical prognosis in MIS-TLIF.展开更多
BACKGROUND： Computed Tomography （CT） and Magnetic Resonance Imaging （MRI） can display the site of lumbar spinal stenosis and predict nervous compression at the morphological level; however, pure morphological cha...BACKGROUND： Computed Tomography （CT） and Magnetic Resonance Imaging （MRI） can display the site of lumbar spinal stenosis and predict nervous compression at the morphological level; however, pure morphological changes cannot reflect functional alterations in a compressed nerve root. Dermatomal somatosensory evoked potential （DSEP） provides a means to assess the functional state of a nerve root. OBJECTIVE： To evaluate the clinical significance of DSEP, assessing the degree of nerve root injury following lumbar spinal stenosis. DESIGN, TIME AND SETTING： A case-control study was performed in the Department of Orthopaedic Surgery, Hainan People＇s Hospital, China, between September 2004 and December 2007. PARTICIPANTS： Forty-seven patients diagnosed with lumbar spinal stenosis by CT or MRI were selected as the case group; fifty healthy subjects were collected as the control group. METHODS： A KEYPOINT myoelectric evoked potential apparatus （DANTEC Company, Denmark） was used to measure DSEP, and stimulative spots were determined in accordance with the skin key sensory spot standards established by The American Spinal Injury Association： L4 in the medial malleolus, L5 in the third metatarsophalangeal joint of the dorsum of foot and S1 in the lateral heel. The needle electrode used as the recording electrode was located at the Cz point of the cranium, and the reference electrode at the Fz point. MAIN OUTCOME MEASURES： Latency of the P40 peak of DSEP, P1-N1 amplitude, P40 waveform and differentiation and disappearance of various waves. RESULTS： The sensitivity and diagnostic concurrence with surgery of nerve root injury following lumbar spinal stenosis evaluated by DSEP was 95.7 %. P40 latencies at L4, L5 and S1 in the case group were significantly longer than in the control group （P 〈 0.05）, and the P1-N1 amplitude in the case group was significantly lower than the control group （P 〈 0.05-0.01）. Nerve root injury was categorized according to DSEP latency as follows： severe damage （disappearance of the P40 wave in 103 dermatomes）, moderate damage （prolongation of the P40 peak latency ≥ 3.0 times the standard deviation of the normal mean in 60 dermatomes） and mild damage （prolongation of the P40 peak latency ≥ 2.5 times the standard deviation of the normal mean in 31 dermatomes）. CONCLUSION： DSEP can be used to determine the severity of nerve root injury following lumbar spinal stenosis with high sensitivity and specificity.展开更多
基金National Natural Science Foundation of China(No.82160435)。
文摘Objective:To analyze the correlation between the amplitude changes of motor evoked potential(MEP),the 3D volume changes of spinal canal measuring by postoperative CT and the improvement rate of clinical symptoms after the spinal canal decompression in minimally invasive transforaminal lumbar interbody fusion(MIS-TLIF),and to explore the predictive value of the changes of both MEP amplitude and spinal canal volume in the assessment of long-term clinical prognosis in MIS-TLIF.Methods:A retrospective study of 68 patients with L4/5 spinal stenosis treated with MIS-TLIF was performed.The changes of both intraoperative MEP amplitude and 3D spinal canal volume during the spinal canal decompression,as well as the visual analogue scale(VAS)and Oswestry dysfunction index(ODI)scores in the long-term follow-up were all recorded.Results:The values of intraoperative MEP amplitude was 159.04%higher in 68 patients with MIS-TLIF after spinal canal decompression(P<0.01).The 3 postoperative 3D spinal canal volume(4.89±1.27)cm increased by 31.22%in comparison 3 with preoperative date(3.78±1.08)cm(P<0.01).The VAS and ODI scores were improved to 78.55%and 80.60%,respectively at the last follow-up(P<0.01).The improvement rate of MEP amplitude on the decompression side was positively correlated with the improvement rate of postoperative spinal canal volume(r=0.272,P=0.025).The improvement rate of postoperative spinal canal volume was positively correlated with the improvement rate of VAS and ODI at the last follow-up(r=0.656,r=0.490,P<0.01).Moreover,the improvement rate of MEP amplitude on the decompression side was also positively correlated with the improvement rate of VAS and ODI at the last follow-up(r=0.322 and 0.235,respectively,P<0.05).Conclusion:The increase of MEP amplitude after spinal canal decompression in patients with lumbar spinal stenosis treated by MIS-TLIF was closely correlated with both of the increase of spinal canal volume and the improvement of clinical symptoms.Therefore,MEP amplitude monitoring was not only the one of the important monitoring methods for predicting the prognosis of MIS-TLIF but also the reliably predictive value in the long-term clinical prognosis in MIS-TLIF.
基金the National Natural Science Foundation of Hainan Province,No.30318
文摘BACKGROUND： Computed Tomography （CT） and Magnetic Resonance Imaging （MRI） can display the site of lumbar spinal stenosis and predict nervous compression at the morphological level; however, pure morphological changes cannot reflect functional alterations in a compressed nerve root. Dermatomal somatosensory evoked potential （DSEP） provides a means to assess the functional state of a nerve root. OBJECTIVE： To evaluate the clinical significance of DSEP, assessing the degree of nerve root injury following lumbar spinal stenosis. DESIGN, TIME AND SETTING： A case-control study was performed in the Department of Orthopaedic Surgery, Hainan People＇s Hospital, China, between September 2004 and December 2007. PARTICIPANTS： Forty-seven patients diagnosed with lumbar spinal stenosis by CT or MRI were selected as the case group; fifty healthy subjects were collected as the control group. METHODS： A KEYPOINT myoelectric evoked potential apparatus （DANTEC Company, Denmark） was used to measure DSEP, and stimulative spots were determined in accordance with the skin key sensory spot standards established by The American Spinal Injury Association： L4 in the medial malleolus, L5 in the third metatarsophalangeal joint of the dorsum of foot and S1 in the lateral heel. The needle electrode used as the recording electrode was located at the Cz point of the cranium, and the reference electrode at the Fz point. MAIN OUTCOME MEASURES： Latency of the P40 peak of DSEP, P1-N1 amplitude, P40 waveform and differentiation and disappearance of various waves. RESULTS： The sensitivity and diagnostic concurrence with surgery of nerve root injury following lumbar spinal stenosis evaluated by DSEP was 95.7 %. P40 latencies at L4, L5 and S1 in the case group were significantly longer than in the control group （P 〈 0.05）, and the P1-N1 amplitude in the case group was significantly lower than the control group （P 〈 0.05-0.01）. Nerve root injury was categorized according to DSEP latency as follows： severe damage （disappearance of the P40 wave in 103 dermatomes）, moderate damage （prolongation of the P40 peak latency ≥ 3.0 times the standard deviation of the normal mean in 60 dermatomes） and mild damage （prolongation of the P40 peak latency ≥ 2.5 times the standard deviation of the normal mean in 31 dermatomes）. CONCLUSION： DSEP can be used to determine the severity of nerve root injury following lumbar spinal stenosis with high sensitivity and specificity.
