Fine motor skills are thought to rely on the integrity of ascending sensory pathways in the spinal dorsal column as well as descending motor pathways that have a neocortical origin.However, the neurophysiological proc...Fine motor skills are thought to rely on the integrity of ascending sensory pathways in the spinal dorsal column as well as descending motor pathways that have a neocortical origin.However, the neurophysiological processes underlying communication between the somatosensory and motor pathways that regulate fine motor skills during spontaneous recovery after spinal cord contusion injury remain unclear.Here, we established a rat model of cervical hemicontusive injury using C5 laminectomy followed by contusional displacement of 1.2 mm(mild injury) or 2.0 mm(severe injury) to the C5 spinal cord.Electrophysiological recordings were performed on the brachial muscles up to 12 weeks after injury to investigate the mechanisms by which spinal cord pathways participate in motor function.After spinal cord contusion injury, the amplitudes of somatosensory and motor-evoked potentials were reduced, and the latencies were increased.The forelimb open field locomotion test, grooming test, rearing test and Montoya staircase test revealed improvement in functions.With increasing time after injury, the amplitudes of somatosensory and motor-evoked potentials in rats with mild spinal cord injury increased gradually, and the latencies gradually shortened.In comparison, the recovery times of somatosensory and motor-evoked potential amplitudes and latencies were longer, and the recovery of motor function was delayed in rats with severe spinal cord injury.Correlation analysis revealed that somatosensoryevoked potential and motor-evoked potential parameters were correlated with gross and fine motor function in rats with mild spinal cord contusion injury.In contrast, only somatosensory-evoked potential amplitude was correlated with fine motor skills in rats with severe spinal cord injury.Our results show that changes in both somatosensory and motor-evoked potentials can reflect the changes in gross and fine motor functions after mild spinal cord contusion injury, and that the change in somatosensory-evoked potential amplitude can also reflect the change in fine motor function after severe spinal cord contusion injury.This study was approved by the Animal Ethics Committee of Nanfang Hospital, Southern Medical University, China(approval No.NFYY-2017-67) on June 11, 2017.展开更多
Background:Spinal cord ischaemia animal models were established by selective ligation of the lumbar artery in a craniocaudal direction between the renal artery and the aortic bifurcation.Transcranial electrical stimul...Background:Spinal cord ischaemia animal models were established by selective ligation of the lumbar artery in a craniocaudal direction between the renal artery and the aortic bifurcation.Transcranial electrical stimulation motor-evoked potentials were measured to enable their use in future studies on spinal cord ischaemia protection.Methods:Thirty-three New Zealand rabbits were randomly divided into 6 groups.Transcranial electrical stimulation motor-evoked potentials were recorded before vascular ligation,30 min after vascular ligation,and 2days after vascular ligation.Motor functions were assessed after surgery and 2 days after vascular ligation.The specimens were taken 2 days after ligation for histopathologic observation.Results:With increased numbers of ligations,a transient extension of the latency became clear,but there were no significant differences in the statistical analysis.Analysis of variance after ligation at the same time in each group and t tests before and after ligation(P>0.05)were not significant.One or 2 ligations did not cause spinal cord ischaemic damage.There were no significant differences before and after ligation for the amplitude(P>0.05).With increased numbers of ligations,the amplitude before and after ligation was gradually reduced in the 3-5 ligation groups(P<0.05).Conclusions:Ligation of segmental spinal cord vessels on 1 or 2 levels did not cause ischaemic damage.Spinal cord ischaemia was observed after 3,4,or 5 ligations.The amplitude was more sensitive to spinal cord ischaemia than latency.Spinal cord function can be predicted by early changes in the amplitude.展开更多
Multi-target neural circuit-magnetic stimulation has been clinically shown to improve rehabilitation of lower limb motor function after spinal cord injury. However, the precise underlying mechanism remains unclear. In...Multi-target neural circuit-magnetic stimulation has been clinically shown to improve rehabilitation of lower limb motor function after spinal cord injury. However, the precise underlying mechanism remains unclear. In this study, we performed double-target neural circuit-magnetic stimulation on the left motor cortex and bilateral L5 nerve root for 3 successive weeks in a rat model of incomplete spinal cord injury caused by compression at T10. Results showed that in the injured spinal cord, the expression of the astrocyte marker glial fibrillary acidic protein and inflammatory factors interleukin 1β, interleukin-6, and tumor necrosis factor-α had decreased, whereas that of neuronal survival marker microtubule-associated protein 2 and synaptic plasticity markers postsynaptic densification protein 95 and synaptophysin protein had increased. Additionally, neural signaling of the descending corticospinal tract was markedly improved and rat locomotor function recovered significantly. These findings suggest that double-target neural circuit-magnetic stimulation improves rat motor function by attenuating astrocyte activation, thus providing a theoretical basis for application of double-target neural circuit-magnetic stimulation in the clinical treatment of spinal cord injury.展开更多
Studies have confirmed that low-frequency repetitive transcranial magnetic stimulation can decrease the activity of cortical neurons, and high-frequency repetitive transcranial magnetic stimulation can increase the ex...Studies have confirmed that low-frequency repetitive transcranial magnetic stimulation can decrease the activity of cortical neurons, and high-frequency repetitive transcranial magnetic stimulation can increase the excitability of cortical neurons. However, there are few studies concerning the use of different frequencies of repetitive transcranial magnetic stimulation on the recovery of upper-limb motor function after cerebral infarction. We hypothesized that different frequencies of repetitive transcranial magnetic stimulation in patients with cerebral infarction would produce different effects on the recovery of upper-limb motor function. This study enrolled 127 patients with upper-limb dysfunction during the subacute phase of cerebral infarction. These patients were randomly assigned to three groups. The low-frequency group comprised 42 patients who were treated with 1 Hz repetitive transcranial magnetic stimulation on the contralateral hemisphere primary motor cortex(M1). The high-frequency group comprised 43 patients who were treated with 10 Hz repetitive transcranial magnetic stimulation on ipsilateral M1. Finally, the sham group comprised 42 patients who were treated with 10 Hz of false stimulation on ipsilateral M1. A total of 135 seconds of stimulation was applied in the sham group and high-frequency group. At 2 weeks after treatment, cortical latency of motor-evoked potentials and central motor conduction time were significantly lower compared with before treatment. Moreover, motor function scores were significantly improved. The above indices for the low- and high-frequency groups were significantly different compared with the sham group. However, there was no significant difference between the low- and high-frequency groups. The results show that low- and high-frequency repetitive transcranial magnetic stimulation can similarly improve upper-limb motor function in patients with cerebral infarction.展开更多
Recently, many surgeons have been using intraoperative neurophysiological monitoring(IOM) in spinal surgery to reduce the incidence of postoperative neurological complications, including level of the spinal cord, caud...Recently, many surgeons have been using intraoperative neurophysiological monitoring(IOM) in spinal surgery to reduce the incidence of postoperative neurological complications, including level of the spinal cord, cauda equina and nerve root. Several established technologies are available and combined motor and somatosensory evoked potentials are considered mandatory for practical and successful IOM. Spinal cord evoked potentials are elicited compound potentials recorded over the spinal cord. Electrical stimulation is provoked on the dorsal spinal cord from an epidural electrode. Somatosensory evoked potentials assess the functional integrity of sensory pathways from the peripheral nerve through the dorsal column and to the sensory cortex. For identification of the physiological midline, the dorsal column mapping technique can be used. It is helpful for reducing the postoperative morbidity associated with dorsal column dysfunction when distortion of the normal spinal cord anatomy caused by an intramedullary cord lesion results in confusion in localizing the midline for the myelotomy. Motor evoked potentials(MEPs) consist of spinal, neurogenic and muscle MEPs. MEPs allow selective and specific assessment of the functional integrity of descending motor pathways, from the motor cortex to peripheral muscles. Spinal surgeons should understand the concept of the monitoring techniques and interpret monitoring records adequately to use IOM for the decision making during the surgery for safe surgery and a favorable surgical outcome.展开更多
Classic paired associative stimulation can improve synaptic plasticity,as demonstrated by animal expe riments and human clinical trials in spinal cord injury patients.Paired associative magnetic stimulation(dual-targe...Classic paired associative stimulation can improve synaptic plasticity,as demonstrated by animal expe riments and human clinical trials in spinal cord injury patients.Paired associative magnetic stimulation(dual-target peripheral and central magnetic stimulation)has been shown to promote neurologic recove ry after stroke.However,it remains unclear whether paired associative magnetic stimulation can promote recovery of lower limb motor dysfunction after spinal cord injury.We hypothesize that the curre nt caused by central and peripheral magnetic stimulation will conve rge at the synapse,which will promote synapse function and improve the motor function of the relevant muscles.Therefore,this study aimed to examine the effects of paired associative magnetic stimulation on neural circuit activation by measuring changes in motor evoked and somatosensory evoked potentials,motor and sensory function of the lower limbs,functional health and activities of daily living,and depression in patients with spinal co rd injury.We will recruit 110 thora cic spinal trauma patients treated in the Department of Spinal Cord Injury,China Rehabilitation Hospital and randomly assign them to expe rimental and control groups in a 1:1 ratio.The trial group(n=55)will be treated with paired associative magnetic stimulation and conventional rehabilitation treatment.The control group(n=55)will be treated with sham stimulation and co nventional rehabilitation treatment.Outcomes will be measured at four time points:baseline and 4,12,and 24 wee ks after the start of inte rvention(active or sham paired associative magnetic stimulation).The primary outcome measure of this trial is change in lower limb American Spinal Injury Association Impairment Scale motor function score from baseline to last follow-up.Secondary outcome measures include changes in lower limb American Spinal Injury Association sensory function sco re,motor evoked potentials,sensory evoked potentials,modified Ashwo rth scale score,Maslach Burnout Invento ry score,and Hamilton Depression Scale score over time.Motor evoked potential latency reflects corticospinal tract transmission time,while amplitude reflects recruitment ability;both measures can help elucidate the mechanism underlying the effect of paired associative magnetic stimulation on synaptic efficiency.Adve rse events will be recorded.Findings from this trial will help to indicate whether paired associative magnetic stimulation(1)promotes recove ry of lower limb sensory and motor function,reduces spasticity,and improves quality of life;(2)promotes neurologic recovery by increasing excitability of spinal cord motor neurons and stimulating synaptic plasticity;and(3)improves rehabilitation outcome in patients with spinal cord injury.Recruitment for this trial began in April 2021 and is currently ongoing.It was approved by the Ethics Committee of Yangzhi Affiliated Rehabilitation Hospital of Tongji University,China(approval No.YZ2020-018)on May 18,2020.The study protocol was registered in the Chinese Clinical Trial Registry(registration number:ChiCTR2100044794)on March 27,2021(protocol version 1.0).This trial will be completed in April 2022.展开更多
基金supported by the National Natural Science Foundation of China, No.81871768(to YH)Chinese Academy of Medical Sciences Initiative for Innovative Medicine of China, No.2016-I2 M-2-006(to HYC)High Level-Hospital Program, Health Commission of Guangdong Province, China, No.HKUSZH201902011(to YH)。
文摘Fine motor skills are thought to rely on the integrity of ascending sensory pathways in the spinal dorsal column as well as descending motor pathways that have a neocortical origin.However, the neurophysiological processes underlying communication between the somatosensory and motor pathways that regulate fine motor skills during spontaneous recovery after spinal cord contusion injury remain unclear.Here, we established a rat model of cervical hemicontusive injury using C5 laminectomy followed by contusional displacement of 1.2 mm(mild injury) or 2.0 mm(severe injury) to the C5 spinal cord.Electrophysiological recordings were performed on the brachial muscles up to 12 weeks after injury to investigate the mechanisms by which spinal cord pathways participate in motor function.After spinal cord contusion injury, the amplitudes of somatosensory and motor-evoked potentials were reduced, and the latencies were increased.The forelimb open field locomotion test, grooming test, rearing test and Montoya staircase test revealed improvement in functions.With increasing time after injury, the amplitudes of somatosensory and motor-evoked potentials in rats with mild spinal cord injury increased gradually, and the latencies gradually shortened.In comparison, the recovery times of somatosensory and motor-evoked potential amplitudes and latencies were longer, and the recovery of motor function was delayed in rats with severe spinal cord injury.Correlation analysis revealed that somatosensoryevoked potential and motor-evoked potential parameters were correlated with gross and fine motor function in rats with mild spinal cord contusion injury.In contrast, only somatosensory-evoked potential amplitude was correlated with fine motor skills in rats with severe spinal cord injury.Our results show that changes in both somatosensory and motor-evoked potentials can reflect the changes in gross and fine motor functions after mild spinal cord contusion injury, and that the change in somatosensory-evoked potential amplitude can also reflect the change in fine motor function after severe spinal cord contusion injury.This study was approved by the Animal Ethics Committee of Nanfang Hospital, Southern Medical University, China(approval No.NFYY-2017-67) on June 11, 2017.
基金the fund of the health department of Shandong Province,China(2011QW008 and 2015WS0375).
文摘Background:Spinal cord ischaemia animal models were established by selective ligation of the lumbar artery in a craniocaudal direction between the renal artery and the aortic bifurcation.Transcranial electrical stimulation motor-evoked potentials were measured to enable their use in future studies on spinal cord ischaemia protection.Methods:Thirty-three New Zealand rabbits were randomly divided into 6 groups.Transcranial electrical stimulation motor-evoked potentials were recorded before vascular ligation,30 min after vascular ligation,and 2days after vascular ligation.Motor functions were assessed after surgery and 2 days after vascular ligation.The specimens were taken 2 days after ligation for histopathologic observation.Results:With increased numbers of ligations,a transient extension of the latency became clear,but there were no significant differences in the statistical analysis.Analysis of variance after ligation at the same time in each group and t tests before and after ligation(P>0.05)were not significant.One or 2 ligations did not cause spinal cord ischaemic damage.There were no significant differences before and after ligation for the amplitude(P>0.05).With increased numbers of ligations,the amplitude before and after ligation was gradually reduced in the 3-5 ligation groups(P<0.05).Conclusions:Ligation of segmental spinal cord vessels on 1 or 2 levels did not cause ischaemic damage.Spinal cord ischaemia was observed after 3,4,or 5 ligations.The amplitude was more sensitive to spinal cord ischaemia than latency.Spinal cord function can be predicted by early changes in the amplitude.
基金supported by the National Natural Science Foundation of China,Nos. 81772453 and 81974358 (both to DSX)Shanghai Municipal Key Clinical Specialty Program,No. shslczdzk02701 (to QX)。
文摘Multi-target neural circuit-magnetic stimulation has been clinically shown to improve rehabilitation of lower limb motor function after spinal cord injury. However, the precise underlying mechanism remains unclear. In this study, we performed double-target neural circuit-magnetic stimulation on the left motor cortex and bilateral L5 nerve root for 3 successive weeks in a rat model of incomplete spinal cord injury caused by compression at T10. Results showed that in the injured spinal cord, the expression of the astrocyte marker glial fibrillary acidic protein and inflammatory factors interleukin 1β, interleukin-6, and tumor necrosis factor-α had decreased, whereas that of neuronal survival marker microtubule-associated protein 2 and synaptic plasticity markers postsynaptic densification protein 95 and synaptophysin protein had increased. Additionally, neural signaling of the descending corticospinal tract was markedly improved and rat locomotor function recovered significantly. These findings suggest that double-target neural circuit-magnetic stimulation improves rat motor function by attenuating astrocyte activation, thus providing a theoretical basis for application of double-target neural circuit-magnetic stimulation in the clinical treatment of spinal cord injury.
基金several colleague therapists of the Rehabilitation Medicine Department of the Affiliated Hospital of Qingdao University of China for their support and selfless help
文摘Studies have confirmed that low-frequency repetitive transcranial magnetic stimulation can decrease the activity of cortical neurons, and high-frequency repetitive transcranial magnetic stimulation can increase the excitability of cortical neurons. However, there are few studies concerning the use of different frequencies of repetitive transcranial magnetic stimulation on the recovery of upper-limb motor function after cerebral infarction. We hypothesized that different frequencies of repetitive transcranial magnetic stimulation in patients with cerebral infarction would produce different effects on the recovery of upper-limb motor function. This study enrolled 127 patients with upper-limb dysfunction during the subacute phase of cerebral infarction. These patients were randomly assigned to three groups. The low-frequency group comprised 42 patients who were treated with 1 Hz repetitive transcranial magnetic stimulation on the contralateral hemisphere primary motor cortex(M1). The high-frequency group comprised 43 patients who were treated with 10 Hz repetitive transcranial magnetic stimulation on ipsilateral M1. Finally, the sham group comprised 42 patients who were treated with 10 Hz of false stimulation on ipsilateral M1. A total of 135 seconds of stimulation was applied in the sham group and high-frequency group. At 2 weeks after treatment, cortical latency of motor-evoked potentials and central motor conduction time were significantly lower compared with before treatment. Moreover, motor function scores were significantly improved. The above indices for the low- and high-frequency groups were significantly different compared with the sham group. However, there was no significant difference between the low- and high-frequency groups. The results show that low- and high-frequency repetitive transcranial magnetic stimulation can similarly improve upper-limb motor function in patients with cerebral infarction.
文摘Recently, many surgeons have been using intraoperative neurophysiological monitoring(IOM) in spinal surgery to reduce the incidence of postoperative neurological complications, including level of the spinal cord, cauda equina and nerve root. Several established technologies are available and combined motor and somatosensory evoked potentials are considered mandatory for practical and successful IOM. Spinal cord evoked potentials are elicited compound potentials recorded over the spinal cord. Electrical stimulation is provoked on the dorsal spinal cord from an epidural electrode. Somatosensory evoked potentials assess the functional integrity of sensory pathways from the peripheral nerve through the dorsal column and to the sensory cortex. For identification of the physiological midline, the dorsal column mapping technique can be used. It is helpful for reducing the postoperative morbidity associated with dorsal column dysfunction when distortion of the normal spinal cord anatomy caused by an intramedullary cord lesion results in confusion in localizing the midline for the myelotomy. Motor evoked potentials(MEPs) consist of spinal, neurogenic and muscle MEPs. MEPs allow selective and specific assessment of the functional integrity of descending motor pathways, from the motor cortex to peripheral muscles. Spinal surgeons should understand the concept of the monitoring techniques and interpret monitoring records adequately to use IOM for the decision making during the surgery for safe surgery and a favorable surgical outcome.
基金the National Key Research and Development Program of China,No.2020YFC2004202(to DSX)the National Natural Science Foundation of China(General Program),Nos.81772453,81974358(to DSX)Scientific Research Project of Yangzhi Rehabilitation Hospital Affliated to Tongji University,No.KYPY202006(to TTS)。
文摘Classic paired associative stimulation can improve synaptic plasticity,as demonstrated by animal expe riments and human clinical trials in spinal cord injury patients.Paired associative magnetic stimulation(dual-target peripheral and central magnetic stimulation)has been shown to promote neurologic recove ry after stroke.However,it remains unclear whether paired associative magnetic stimulation can promote recovery of lower limb motor dysfunction after spinal cord injury.We hypothesize that the curre nt caused by central and peripheral magnetic stimulation will conve rge at the synapse,which will promote synapse function and improve the motor function of the relevant muscles.Therefore,this study aimed to examine the effects of paired associative magnetic stimulation on neural circuit activation by measuring changes in motor evoked and somatosensory evoked potentials,motor and sensory function of the lower limbs,functional health and activities of daily living,and depression in patients with spinal co rd injury.We will recruit 110 thora cic spinal trauma patients treated in the Department of Spinal Cord Injury,China Rehabilitation Hospital and randomly assign them to expe rimental and control groups in a 1:1 ratio.The trial group(n=55)will be treated with paired associative magnetic stimulation and conventional rehabilitation treatment.The control group(n=55)will be treated with sham stimulation and co nventional rehabilitation treatment.Outcomes will be measured at four time points:baseline and 4,12,and 24 wee ks after the start of inte rvention(active or sham paired associative magnetic stimulation).The primary outcome measure of this trial is change in lower limb American Spinal Injury Association Impairment Scale motor function score from baseline to last follow-up.Secondary outcome measures include changes in lower limb American Spinal Injury Association sensory function sco re,motor evoked potentials,sensory evoked potentials,modified Ashwo rth scale score,Maslach Burnout Invento ry score,and Hamilton Depression Scale score over time.Motor evoked potential latency reflects corticospinal tract transmission time,while amplitude reflects recruitment ability;both measures can help elucidate the mechanism underlying the effect of paired associative magnetic stimulation on synaptic efficiency.Adve rse events will be recorded.Findings from this trial will help to indicate whether paired associative magnetic stimulation(1)promotes recove ry of lower limb sensory and motor function,reduces spasticity,and improves quality of life;(2)promotes neurologic recovery by increasing excitability of spinal cord motor neurons and stimulating synaptic plasticity;and(3)improves rehabilitation outcome in patients with spinal cord injury.Recruitment for this trial began in April 2021 and is currently ongoing.It was approved by the Ethics Committee of Yangzhi Affiliated Rehabilitation Hospital of Tongji University,China(approval No.YZ2020-018)on May 18,2020.The study protocol was registered in the Chinese Clinical Trial Registry(registration number:ChiCTR2100044794)on March 27,2021(protocol version 1.0).This trial will be completed in April 2022.
