Objective To explore a new electrodiagnostic approach using the H reflex elicited by magnetic stimulation of the S1 nerve root and F waves to evaluate sensory nerve root function in patients with S1 radiculopathy.Methods Thirty normal subjects and 30 patients with unilateral S1 radiculopathy were recruited in this study.H reflex and M response were recorded from the bilateral soleus of all the subjects by magnetic stimulation of S1 nerve roots.F and M wave responses elicited by electrical stimulation of bilateral tibial nerves at the popliteal fossa were also recorded.The sensory root conduction time (SRCT) was calculated.Correlations of age and body height with SRCT in the healthy subjects,and between SRCT and pain in the patients with S1 radiculopathy were analyzed.Results The mean values of normal subjects were 3.10 ± 0.44 ms for SRCT,and 0.13 ± 0.19 ms for inter-side SRCT differences.In the 30 patients with S1 radiculopathy,H reflex could not be elicited from 4 patients.Among the remaining patients,the SRCT of the affected side was prolonged significantly (3.90 ±0.65 ms),and the mean value of the inter-side difference increased significantly (0.90 ±0.50 ms).A regression equation correlating SRCT with height was developed,but no significant correlation between SRCT and age in the normal subjects was revealed.There was positive correlation between SRCT and the severity of pain among the patients.Conclusion SRCT can be used as a new electrodiagnostic index in estimating sensory nerve root function in patients with S1 radiculopathy.

Objective To explore the value of a new electrodiagnostic approach for evaluating motor nerve root function in patients with S1 radiculopathy. Methods Thirty healthy subjects and 30 patients with clinical mani-festations of unilateral S1 radiculopathy were recruited. Bilateral compound muscle action potentials evoked by magnetic stimulation of the first sacral nerve root were recorded from the soleus of all the subjects. F wave and M responses to electrical stimulation of the bilateral tibial nerves at the popliteal fossa were also recorded. The peripheral motor conduction time (PMCT) and the motor root conduction time (MRCT) were calculated and compared between the two groups. In addition, needle electromyographic examination (NEE) was performed on the affected side to detect any possible EMG abnormalities. Results The norm established with the normal subjects was 3.45±0.39 ms for the MRCT, and 0.28±0.15 ms for the inter-side difference in the MRCT. In the 30 patients, the mean MRCT and PMCT values on the affected side were prolonged. Of the 23 patients who received NEE, 6 had EMG abnormalities. The agreement between the NEE and MRCT diagnoses was 82.6%. Conclusion MRCT can be used reliably for non-invasive estimation of motor nerve root function and to help diagnose the S1 radiculopathy.

Objective In order to explore the mechanism of repetitive transcranial magnetic stimulation rTMS) on neuropathic pain,we observed the effect of different frequencies of rTMS on neuropathic pain and the expression of neuronal nitric oxide synthase (nNOS) in the dorsal root ganglion (DRG).Methods A total of 28 male Sprague-Dawley rats were used and divided into a control group,in which sham-operation was performed,and an experimental group which was further divided into a sham-rTMS group,a 1 Hz group and a 20 Hz group after successful neuropathic pain model was established by operation to ligate the left sciatic nerves,with 7 rats in each group.Three days after the operation,rTMS was applied to the primary motor cortex (M1) contralateral to the pain once dai ly for 10 consecutive days.The pain behavior and nNOS expression in the DRG were measured before and after 10 days of rTMS intervention.Results All the neuropathic pain model rats demonstrated pain-related behaviors 3 days postoperation,the mechanical pain thresholds were significantly lower than those in the control group (P ＜ 0.05).After rTMS treatment,the mechanical hyperalgsia was significantly relieved in 20 Hz group but not 1 Hz group as demonstrated by a comparison with the sham-rTMS group (P ＜ 0.05).The expression of nNOS in DRG ipsilateral to the neuropathic pain was significantly increased in sham-rTMS group and 1 Hz group (P ＜ 0.05) when compared with the control group.Meanwhile,it was shown that expression of nNOS was down-regulated in 20 Hz group but not 1 Hz group (P ＜ 0.05).The degree of pain relief in 20 Hz group was negatively correlated with the expression of nNOS in DRG (P ＜0.05).Conclusions Neuropathic pain induced by peripheral nerve injury is associated with elevated expression of nNOS in the DRG.High-frequency rTMS can relieve neuropathic pain through down-regulating the overexpression of nNOS in the DRG,but the low-frequency rTMS has no such effect.

Objective To observe the effects of repeated low and high-frequency transcranial magnetic stimulation (rTMS) on neuropathic pain and the expression of specific activation markers of astrocytes and glial fibrillary acidic protein (GFAP) in the lumbar spinal cord.Methods Twenty-eight male Sprague-Dawley rats were randomly divided into a sham-operated group,a sham-rTMS group,a 1 Hz group and a 20 Hz group,with 7 in each group.The rats in the sham-operated group had their sciatic nerve exposed without ligation,while the other groups underwent sciatic nerve ligation to induce neuropathic pain.Three days after the operation,rTMS was applied to the primary motor cortex (M1) contralateral to the pain once a day for 10 consecutive days.Pain-related behavior and thermal pain response were tested before the operation and before and after the course of rTMS therapy.The expression of GFAP in the lumbar spinal cord was examined.Results All of the rats which underwent sciatic nerve ligation showed pain-related behavior and significantly decreasing thermal pain latency compared with the sham-operated group.After the rTMS therapy the thermal hyperalgia was significantly attenuated in the 20 Hz group but not in the 1 Hz group compared with the sham-rTMS group.The expression of GFAP in the dorsal horn of the lumbar spinal cord ipsilateral to the neuropathic pain was significantly increased in the sham-rTMS group and the 1 Hz group compared with the sham-operated group.Compared with the sham-rTMS group,GFAP levels were significantly lower in the 20 Hz group but not in the 1 Hz group.The pain relief in the 20 Hz group was negatively related to the expression of GFAP.Conclusions Neuropathic pain induced by peripheral nerve injury is associated with increased activity and proliferation of astrocytes in the dorsal horns of the spinal cord.High-frequency rTMS can relieve neuropathic pain through inhibiting the activity and proliferation of astrocytes in the dorsal horns,but low-frequency rTMS has no clinically significant effect.

Objective To investigate the effects of magnetic stimulation (MS) on the proliferation and differentiation of endogenous neural stem cells (NSCs)/progenitor cells after spinal cord injury (SCI) in rats. Methods Forty-six Wistar rats were used, of which 40 were used to make an animal model of spinal cord injury (SCI) by administering a 10 g x 12.5 cm impact at the T8 level. The other 6 served as the normal controls. The SCI model rats were evenly divided into a magnetic stimulation (MS) group ( n = 20) and a control group ( n = 20). The rats in the MS group received 0.5 Hz and 1.44 T magnetic stimulation 24 h post injury, then 30 pulses per day for 7 days. The rats in the other groups were not exposed to MS. The scale of Basso, Beatti and Bresnahan (BBB) was used to assess hindlimb neurological function. Rats were sacrificed at the 24th hour, and at the 1st, 4th and 8th weeks after SCI. The ratio of nestin to microtubule associated protein 2 (MAP2)/nestin in the cells of the spinal cord was determined by immunofluorescence. Results The BBB scores in the MS group were signifi-cantly higher than those of the control group at 1, 4 and 8 weeks post SCI. Nestin and the MAP2/nestin ratios were mild in the normal spinal cords, but increased after SCI. They were higher in the MS group than that in the control groups at all time points. Conclusions MS can promote nestin expression in the spinal cord after SCI and facili-tate neural differentiation.

Objective To compare the functional profiles of organ transplant patients using the International Classification of Functioning,Disability,and Health (ICF) core set.Methods The patients were enrolled 5 to 10 days after discharge following an organ transplant.The Functional Independence Measure (FIM),Barthel Index (BI) and the ICF core set were used to assess them.Analysis was conducted by grouping the kidney transplant patients (group A) separately from the heart,lung and liver transplant patients (group B).The prevalence of sevcre impairment in each group was calculated and compared.Results Average FIM and BI secores were both significantly higher in group A than in group B.No severe or total impairment was observed in group A,but in group B,the prevalence of 5 categories (ie.b455,b730,s430,d415 and d450) was significantly greater than in group A.The most prevalent were poor exercise tolerance (b455,56.8％),low muscle power (b730,54.5％),difficulty in maintaining a body position (d415,54.5％),and impaired walking (d450,45％) With regard to the environment factors,the prevalence of e110 (products or substances for personal consumption) and e120 (products and technology for personal use in daily living) were both significantly different in the two groups.Conclusion Heart,lung and liver transplant patients transplant demonstrated more impairments than the kidney transplant patients.All the organ transplant patients deserve early evaluation for detecting any possible impairment.

Objective To compare the effects of paired associative stimulation (PAS) and repetitive transcranial magnetic stimulation (rTMS) on motor cortex excitability.Methods The baseline corticospinal excitability of the left hemispheres of 10 healthy subjects was measured in terms of resting motor threshold (RMT) and other indicators of motor evoked potentials (MEP).On the following day they received PAS composed of trascranial magnetic stimulation (TMS) to the motor cortex of the left hemisphere and electric stimulation (ES) of the median nerve contralateral to the motor cortex,with an interval of 10ms between the TMS and ES (termed PAS10).The PAS10 was delivered at a frequency of 0.05 Hz and an intensity of 120％ of the RMT,for a total of 90 pulses.The MEP amplitude,MEP latency and RMT were evaluated one minute after the stimulation.After the PAS intervention,an interval of one week was allowed to eliminate any effect of PAS on motor cortex excitability.Then rTMS was delivered to the subjects' left motor cortex at the same time of day at a frequency of 1 Hz and an intensity of 120％ of the RMT,for a total of 1000 pulses.MEP amplitude,MEP latency and RMT were evaluated one minute after the stimulation.The two interventions were compared in terms of MEP amplitude,MEP latency and RMT.Results The average MEP amplitude,MEP latency and RMT at baseline were (2.93 ± 0.99) mV,(20.97 ± 1.67) ms,and (46.06 ±5.32) ％,respectively.One minute after PAS10,the MEP amplitude,MEP latency and RMT were (1.14 ± 0.76) mV,(21.87 ± 1.09) ms and (52.06 ±4.20) ％,respectively.One minute after rTMS,the MEP amplitude and latency and the RMT were (2.24 ± 0.79) mV,(20.88 ± 1.94) ms,and (49.00 ± 4.54) ％,respectively.The differences in MEP amplitude,MEP latency and RMT pre-and post-intervention were (0.69 ± 0.10) mV,(0.09 ±0.05) ms and (3.94 ± 0.93) ％,respectively for rTMS.For PAS10 they were (1.83 ± 0.14) mV,(0.90 ± 0.26)ms and (6.00 ± 1.13)％,respectively.The differences in MEP amplitude decrease and MEP latency lengthening between the two stimulation protocols were significant,but the difference in RMT elevation was not.Conclusion Both PAS10 and low frequency rTMS suppressed motor cortex excitability,but the suppressive effect of PAS10 is more significant.

Objective To evaluate the test-retest and inter-rater reliability of the hand-held pressure algometer as a measuring instrument of pressure pain threshold(PPT).Method A total of 37 healthy subjects were recruited for reliability test.Three raters measured the PPT at 12 body sites of the subjects.Each rater conducted three trials on each site.In the validity test,10 patients with active trigger points in the upper trapezius were recruited and measured by one rater using the pressure algometer for PPT,the visual analogue scale(VAS)was also used to evaluate the pain intensity induced by the trigger point.The intraclass correlation coefficient and Spearman correlation coefficient were calculated to reflect the reliability and validity.Results The test-retest and inter-rater reliabilities were both high(ICC＞0.95),with the measurements by one rater were more reliable than measurements by multiple raters.The inter-rater reliability of PPT measurement obtained by using the mean value of 3 trials was higher than any of the 3 trials alone.The PPT values of the trigger points were higher than those of the normal points,and there was a significantly negative correlation between the PPT values of the trigger points and the VAS scores.Conclusion The intra-and inter-rater PPT measurements in healthy subjects obtained with the hand-held pressure algometer were highly reliable.The algometer was valid for quantifying myofascial trigger point sensitivity.

Objective To investigate the effects of paired associative stimulation (PAS) on the recovery of upper limb motor function in stroke patients,and to analyze the relationship between the change of motor cortex excitability in the contralesional hemisphere and the recovery of motor function in the affected upper limb.Methods Thirty hemiplegic stroke patients were divided randomly into a treatment group and a control group.Both groups were given routine rehabilitation therapy,but the treatment group also received PAS consisting of transcranial magnetic stimulation (TMS) of the intact motor cortex and electrical stimulation (ES) of the median nerve at the wrist of the intact arm with an interval of 10 ms between the TMS and ES (PAS10).The PAS10 was delivered at a frequency of 0.05 Hz and an intensity of 120％ the resting motor threshold (RMT),once daily for 30 minutes,five times a week for 4 weeks.Corticospinal excitability was measured using motor evoked potentials (MEP) and the RMT.The FuglMeyer upper limb assessment (FMA),Brunnstrom staging and the modified Barthel index (MBI) were also applied before and at the end of the 4 weeks of treatment.Correlation was sought between any changes in MEP amplitude,the RMT of the contralesional hemisphere and changes in the FMA results.Results Before the intervention there were no significant differences between the two groups in terms of any of the assessments.After 4 weeks of treatment,all the assessments had changed significantly compared to those before the treatment,but there were still no significant differences between the two groups in terms of any the assessments.After 4 weeks of treatment,the differences in MEP amplitude from the contra-lesional hemisphere and the differences in FMA scores were positively and significantly correlated with a correlation coefficient of r =0.431.The lesioned hemisphere was also positively correlated with the differences in FMA scores with a significant correlation coefficient of r =0.608.Conclusion PAS10 can facilitate the recovery of upper limb motor function.The change in motor cortex excitability of the contra-lesional hemisphere significantly correlates with functional recovery in the upper limb.