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Objective To investigate the characteristics of F-waves in patients with Kennedy's disease.Methods Thirty two patients with Kennedy's disease and 30 male healthy volunteers,who visited the Department of Neurology,Peking Union Medical College Hospital between August 2013 and July 2014,were recruited consecutively for this study.Motor nerve conduction study and F-wave examination were performed on the median,ulnar,tibial and peroneal nerves of all participants.A series of 100 electrical stimuli were employed to obtain F-waves.The F-wave parameters in all tested nerves were compared between patients with Kennedy's disease and normal controls including F-wave minimum latency,F-wave persistence,mean and maximum F-wave amplitude,the frequency of giant F-waves.Results The mean Fwave amplitude (median nerve:patients with Kennedy's disease 375.0 (298.3) μV,healthy volunteers 297.0(145.0) μV,Z =-3.378,P ＜0.01;ulnar nerve:patients with Kennedy's disease 397.5(295.0) μV,healthy volunteers 293.0 (101.8) μV,Z =-3.968,P ＜ 0.01;tibial nerve:patients with Kennedy's disease 374.5 (227.3) μV,healthy volunteers 294.0 (160.5) μV,Z =-3.144,P =0.002;peroneal nerve:patients with Kennedy's disease 346.5 (292.8) μV,healthy volunteers 146.5 (69.3) μV,Z =-6.864,P ＜ 0.01),maximum F-wave amplitudes (median nerve:patients with Kennedy's disease 1 291.0 (952.0) μV,healthy volunteers 846.5 (523.0) μV,Z =-4.823,P ＜ 0.01;ulnar nerve:patients with Kennedy's disease 1 663.5 (1 374.0) μV,healthy volunteers 760.5 (341.8) μV,Z =-6.813,P ＜ 0.01;tibial nerve:patients with Kennedy's disease (1 054.1 ± 451.6) μV,healthy volunteers (652.5-± 172.5) μV,t =5.380,P ＜ 0.01;peroneal nerve:patients with Kennedy's disease (840.4 ± 494.1) μV,healthy volunteers (370.2 ± 202.0) μV,t =6.475,P ＜ 0.01),frequency of giant F-waves (median nerve:patients with Kennedy's disease 0.0％ (7.2％),healthy volunteers 0.0％ (0.0％),Z =-5.149,P ＜ 0.01;ulnar nerve:patients with Kennedy's disease 3.1％ (10.5％),healthy volunteers 0.0％ (0.0％),Z =-7.026,P ＜0.01;tibial nerve:patients with Kennedy's disease 0.0％ (3.3％),healthy volunteers 0.0％ (0.0％),Z =-4.651,P ＜0.01;peroneal nerve:patients with Kennedy's disease 3.3％ (28.2％),healthy volunteers 0.0％ (0.0％),Z =-5.532,P ＜0.01),and frequencies of patients with giant F-waves (median nerve:patients with Kennedy's disease 78.1％ (25/32),healthy volunteers 10.0％ (3/30),x2 =29.016,P ＜ 0.01;ulnar nerve:patients with Kennedy's disease 87.5％ (28/32),healthy volunteers 10.0％ (3/30),x2 =37.200,P ＜ 0.01;tibial nerve:patients with Kennedy's disease 62.5％ (20/32),healthy volunteers 6.7％ (2/30),x2 =21.085,P ＜ 0.01;peroneal nerve:patients with Kennedy's disease 68.8 ％ (22/32),healthy volunteers 10.0％ (3/30),x2 =22.209,P ＜ 0.01) in all nerves examined were significantly higher in patients with Kennedy's disease than in the normal controls.The F-wave persistence in all nerves examined was significantly lower than in the normal controls (median nerve:patients with Kennedy's disease 52.5％ (36.3％),healthy volunteers 98.0％ (7.0％),Z =9.010,P ＜ 0.01;ulnar nerve:patients with Kennedy's disease 71.0％ (28.3％),healthy volunteers 100.0％ (1.0％),Z =9.455,P ＜ 0.01;tibial nerve:patients with Kennedy's disease 100.0％ (2.0％),healthy volunteers 100.0％ (0.0％),Z =4.255,P ＜ 0.01;peroneal nerve:patients with Kennedy's disease 33.1％ ± 23.9％,healthy volunteers 46.9％ ± 27.2％,t =-2.848,P =0.007).Giant F-waves were detected in multiple nerves and often appeared symmetrically on the same nerves between the left and right sides in patients with Kennedy's disease.No significant correlations were found between the pooled frequency of giant F-waves and disease duration in patients with Kennedy's disease(r =0.162,P =0.418).Conclusions The results showed increased F-wave amplitudes,increased number of giant F-waves,especially giant F-waves detected in multiple nerves or appearing symmetrically combined with low persistence,consistent with the pathologic features of chronic and unselected loss of anterior horn cells in patients with Kennedy's disease.
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Objective To investigate the clinical features and causes of micturition and defecation dysfunction in motor neuron disease (MND) patients.Methods The micturition and defecation function was evaluated by a questionnaire covering storage and voiding of urine and feces respectively in 50 MND patients.The clinical features and external anal sphincter electromyography (EAS-EMG) were analyzed to explore the causes of micturition and defecation dysfunction in MND patients.Results Micturition and defecation dysfunction was detected in 9 of 50 (18.0％) MND patients.The main types of micturition and defecation dysfunction were constipation (4/9),urinary frequency,urgency with or without incontinence,fecal urgency (4/9),powerlessness for micturition and defecation (2/9),hesitancy for micturition (1/9).EAS-EMG was normal in 9 MND patients accompanied with micturition and defecation dysfunction.Conclusions MND patients accompanied with micturition and defecation dysfunction were not very rare.Constipation,urgency and powerlessness were the main types of micturition and defecation dysfunction and they were not related to the function of external anal sphincter.Gastrointestinal dysfunction from abnormal autonomic nerve involvement,muscle weakness and the resulted reduced activity,severe upper motor neuron damage and respiratory muscle weakness may be the main causes of micturition and defecation dysfunction in MND patients.
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Objective To explore the impact of childbirth on women external anal sphincter electromyography by analysis of motor unit potentials parameters of external anal sphincter electromyography of healthy women volunteers with different childbirth experiences.Methods Twenty-eight healthy volunteers with different childbirth experiences were recruited in this study.Among them , 7 had a history of cesarean and 21 had experienced 1-3 uncomplicated vaginal deliveries ( 12 women had experienced 1, 6 had experienced 2, and 3 had experienced 3).Another 9 nulliparous healthy volunteers were recruited as control group.Among all subjects who completed the examination , parameters of motor unit potentials ( duration, amplitude, area, mean number of turns and mean phases ) of bilateral external anal sphincter were obtained for statistical analysis.Results There were no significant differences in any of the parameters of motor unit potentials between the nulliparous group and the cesarean group , while parameters of durations (10.5 ms vs 9.0 ms, t=-2.506, P=0.019) and mean phases (4.0 vs 3.6, t =-2.707, P=0.012) of vaginal delivery group were significantly higher than that of cesarean group and parameter of durations ( 10.5 ms vs 8.9 ms, t =-3.025, P =0.005 ) of vaginal delivery group was significantly higher than that of the nulliparous group;With increasing numbers of vaginal deliveries , only the parameter of mean turns showed statistically significant differences , although there was a slight trend of larger and more complex motor unit potentials.Compared with subjects without vaginal delivery experience ( including nulliparous group and the cesarean group ) , the parameters of durations and mean phases of subjects with vaginal delivery experience were statistically higher; Nevertheless , parameter of bilateral duration of the motor unit potential preferred asymmetric.Conclusions Childbirth experience has an explicit impact on the parameters of the external anal sphincter motor unit potentials , which is considered to be strongly correlated with the vaginal delivery process rather than the pregnancy procession itself.In addition , the impact is mostly from the first vaginal delivery experience.The characters of asymmetry of motor unit potential parameters imply the possibility of mechanical damage and decrease blood perfusion of tissues during delivery procession.
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Objective To investigate the underlying mechanisms of Miller-Fisher syndrome (MFS) and Bickerstaff' s brainstem encephalitis (BBE) by studying their clinical and electrophysiological characteristics.Methods The clinical and electrophysiological characteristics of 13 MFS and 7 BBE cases in Peking Union Medical College Hospital between 2000 and 2011 were retrospectively analyzed.The electrophysiological parameters included sensory and motor nerve conduction,electromyography,F wave,sympathetic skin response and brainstem auditory evoked potential and blink reflex.Results MFS and BBE had similar clinical characteristics:respiratory symptoms were the most common infectious symptoms before disease onset; Ophthalmoplegia,facial palsy and bulbar symptoms were common; They both had cerebrospinal fluid albuminocytological dissociation and positive serum anti-GQ1b antibody.However,BBE had more central nervous system lesion signs clinically such as conscious disturbance,positive Babinski' s sign and central facial palsy.Electrophysiologically,MFS and BBE also had similar electrophysiological features:sensory nerve abnormality ratios were 6/13,2/7 respectively,with prominently reduced sensory nerve active potential amplitude,normal or slightly slowed sensory conduction velocity; Motor nerves abnormality ratios were 2/13,1/7 respectively,with slightly prolonged distal motor latency and normal compound muscle action potential; Electromyography abnormality ratios were 1/7,0/4 respectively; F wave frequency abnormality ratios were 3/13,5/7 respectively,and in some cases,F wave frequency would restore; Sympathetic skin response abnormality ratios were 1/2,1/3 respectively; Blink reflex abnormalityratios were 1/2,1/1 respectively,with central involvement in BBE; Brainstem auditory evoked potential abnormality ratios were 3/5,1/4 respectively,with wave Ⅰ latency or amplitude abnormality.Conclusion The similarities of clinical and electrophysiological features suggest that MFS and BBE have the same mechanism and they form a continuous spectrum with variable central nervous system and peripheral nervous system involvement.
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Objective To explore the correlation between diffuse neurogenic changes on electromyography and diagnosis of amyotrophic lateral sclerosis (ALS).Methods Retrospective study was performed based on database of motor neuron disorders collected from January,2002 to December,2008.The category of disease with diffuse neurogenic changes at the first examination was summarized.The electromyography (EMG) manifestation in ALS patients at the first examination and the results after follow-up were reviewed.The factors affecting EMG manifestation in ALS were analyzed with binary Logistic regression.Results In 298 patients with diffuse neurogenic changes on EMG,192 cases (64.4％ ) were diagnosed of ALS,36 ( 12.1％ ) progressive muscular atrophy,13 (4.4％ ) Kennedy' s disease,10 (3.4％)Hirayama disease,9 ( 3.0％ ) cervical spondylosis combined with lumbar spondylosis,6 ( 1.3％ ) spinal muscular disease,5 ( 1.7％ ) multifocal motor neuropathy,5 ( 1.7％ ) ALS-plus disease,4 ( 1.3％ )myopathy,3( 1.0％ ) hereditary motor neuropathy,3 ( 1.0％ ) axonal motor neuropathy,2(0.7％ ) postpolio syndrome,and 10 (3.4％) with no definite diagnosis.In total 213 patients who were diagnosed with ALS after follow-up,at their first examinations,8 (3.8％) had neurogenic changes in two regions and 13(6.1％ ) had neurogenic changes in one region,and they all developed to diffuse neurogenic changes after follow-up for 3 to 24 months.Logistic regression analysis showed that the EMG change at first examination was not related to duration from onset,symptom location at onset,age at onset and gender.Conclusion Diffuse neurogenic changes on EMG can present in many disease including ALS.Neurogenie changes in one or two regions on EMG can be the manifestation of ALS at early stage.
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Objective To retrospectively analyze clinical manifestations of autonomic nervous system (ANS) and skin sympathetic response (SSR) in Lambert-Eaton myasthenic syndrome (LEMS).Methods Fifty-three LEMS patients' medical records were reviewed and information regarding clinical symptoms and signs of ANS and SSR testing results were collected.Results ( 1 ) The most common initial symptom of LEMS was weakness of lower extremities ( n =41 ) and the most common symptom of ANS dysfunction was constipation ( n =25 ) and dry-mouth ( n =23),which could be occurred before the onset of the legs (n =7).(2) In symptoms of ANS,cardiovascular system dysfunction was found in 4 patients include one of ingone of bradycardia,one of postural hypotension and 2 of tachycardia- Secretory glands dysfunction was found in 34 patients:23 dry-mouth,6 dry-eyes,and 8 patients sweating dysfunctions.Twenty-eight patients complained of alimentary dysfunction including constipation and diarrhea.Bladder dysfunction was found in 2 patients,who complained of urinary incontinence.Seven male patients complained of sexual dysfunction.Abnormal skin scratch test was found in 17 patients.(3) SSR was performed in 33 patients and 18 found abnormal.Conclusions ANS manifestations are common and prominent in LEMS patients.SSR abnormality is also common in LEMS.More electrophysiology tests are needed in LEMS patients.
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Objective To investigate the F-wave and nerve conduction in patients with amyotrophic lateral sclerosis (ALS) and explore the correlation between these parameters and muscle strength, disease duration and onset site.Methods The data of outpatients and inpatients diagnosed with ALS were collected in Peking Union Medical College Hospital from January 1997 to May 2008.Standard sensory and motor nerve conduction study of the median nerve, ulnar nerve and tibial nerve was performed in 205 patients with ALS.F-wave velocity and frequency was measured in median nerve.Parameters for analyses included sensory conduction velocity and amplitude, distal motor latency (DML), and compound muscle action potential (CMAP) amplitude.Correlation between muscle strength and DML, CMAP amplitude or F-wave frequency were also explored.Results Delayed DML of the median nerve, ulnar nerve and tibial nerve were found in 24.9% (48/193), 15.3% (25/163), 21.2% (7/33) of patients respectively.Decreased CMAP amplitudes were found in 57.0% (110/193), 49.7% (81/163), 39.4% (13/33) of patients respectively.Decreased F-wave frequency of the median nerve was found in 68.9% (122/177) of patients.The abnormality of DML,CMAP amplitude and F-wave frequency of median nerve were increased in weaker muscles.Decreased median nerve CMAP amplitude (81.5% (53/65)) and F-wave abnormality (decreased persistence 70.9%(44/62), absent responses 45.1% (28/62)) in spinal onset groups were significantly higher than those in bulbar onset groups (CMAP 32.4% (11/34); F-wave: decreased persistence 38.2% (13/34), absent responses 14.7% (5/34); x2 = 23.629, 9.753, 9.029,all P <0.01).Compared with the bulbar onset group,the abnormality of DML in spinal onset group was higher, but not reach statistical significance.Logistic regression revealed a strong direct association between decreased CMAP amplitudes and upperextremity muscles strength, disease duration and onset symptom.Abnormality of F-wave frequency was associated with upper-extremity muscles strength and onset symptom.Conclusions Delayed DML and decreased amplitude of CMAP are found in ALS patients.CMAP amplitude is a sensitive parameter related to the severity of ALS.F-wave velocity is relatively normal while F-wave frequency of the median nerve is correlated with muscle strength.Decreasing CMAP amplitude and F-wave frequency are correlated strongly with muscle weakening,disease duration and symptom onset over limbs.
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Objectives To assess the value of external anal sphincter electromyography (EASEMG) in evaluating the related autonomic dysfunction in Parkinson's disease ( PD), parkinsonism dominant multiple system atrophy (MSA-P) and progressive supranuclear palsy (PSP). Methods From the records of EAS-EMG collected in our lab (total 562 cases), 60 PD (male 41, female 19), 68 MSA-P (male 35,female 33) and 13 PSP (male 10, female 3) were included in the analysis in this study. Mean duration,polyphasic ratio and satellite potential occurrence rate were comparable among the groups. Mean duration prolongation were graded as normal ( ＜ 10.0 ms), mild ( 10.0-11.9 ms), moderate ( 12.0-13.9 ms)and severe ( ≥ 14.0 ms). Results Among all related autonomic symptoms, the occurrence rate of constipation, urinary incontinence, urgency and frequency in patients with MSA-P(95.8% (23/24) ,94.6% (53/56) ,87.7% ( 50/57 ), 85.7% (42/49), 76.5% ( 39/51 ) ) were higher than that of PD ( 61.5%(16/26), 62.3% (33/53), 30.6% (15/49), 46.2% (24/52), 45.7% (21/46)) and PSP (75.0%(3/4) , 62.5% (5/8), 50.0% (4/8), 42.9% (3/7), 42.9% (3/7)). The abnormal rate of EAS-EMG in PD, MSA-P and PSP were 60.0%, 94.2% and 84.6%, accordingly. Mean duration ( PD ( 12.0 ± 1.6)ms, MSA-P (15.4±3.0) ms, PSP (13.8±1.8) ms), polyphasic ratio (PD 46.2% ±19.2%, MSA-P 63.9% ± 15.8%, PSP 51.5% ± 12.1% ) and satellite potential occurrence rate ( PD 9.5% ± 8.3%,MSA-P 26.5% ± 15.9%, PSP 19.2% ± 12.5% ) varied significantly different among the groups ( F =31.724, F = 17.412, x2 =45. 335, all P ＜0.01 ). Severe mean duration prolongation was overwhelming in MSA-P (66.2% ) , compared with mild 10.3% and moderate 23.5%. The predominant prolongation degree was moderate in PSP (61.5%, mild 7.7%, severe 30.8% ), and mild in PD (36.7%, moderate 36.7% ,severe 11.7%, normal 15.0% ). Conclusions EAS-EMG could play a role in evaluating the related autonomic dysfunctions in PD, MSA-P and PSP. The EAS-EMG impairment was severe and frequent in MSA-P, mild and infrequent in PD, moderate in PSP. The spectrum of mean duration prolongation suggested the possibility of Onuf's nucleus involvement in these diseases.
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Objective Amyotrophic lateral sclerosis(ALS)is a progressive paralytic disorder resulting from the degeneration of upper and lower motor neurons.Sporadic ALS(SALS)accounm for majority of patients.ALS is a kind of complex disorder.There were several single nucleotide polymorphism (SNP)reported to be associated with SALS in recently published genome-wide association(GWA)study,but there are few data from Asia ALS population and no report focus on SNP which may associated with SALS of Chinese origin.Our study is to screen and add the SNPs related to the risks of SALs in Chinese.Methods Eighty-six individuals with SALS and 94 matched controls were recruited for our study and genomic DNA from blood samples was extracted.Genotypes were determined by a matrix assisted laser desorption/ionization time of flisht mass spectrometry based approach followed by association analysis. Results Individual genotype data for 8 SNPs,rs6700125,rs10260404, rs1942239,rs2279812,rs2405657,rs558889,rs6922711 and rs935 1470 in Chinese population showed no significant association with sporadic ALS.Combining genotype data from published GWA,rs1942239 gained in strength of allelic association(P value decreased to 9.07×10-5 from 1.48×10-4),and rs558889 deviated Hardy-Weinberg equilibrium at ALS case group which may be associated with susceptibility.Conclusions SNP rs1942239 and rs558889 may contribute to susceptibility of sporadic ALS in Chinese patient.The larger sample studies are warranted to confirm the association.
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Objective To identify the mutations in Cu/Zn superoxide dismutase ( SOD1 ) gene in three Chinese kindreds with amyotrophic lateral sclerosis ( ALS), compare the genotypes with those found in other ethnic groups and to analyze the clinical characteristics.Methods The diagnosis of ALS met El Escorial ALS diagnostic criteria.Genomic DNA was extracted from peripheral blood in ALS patients using standard procedure.PCR amplifications of five exons of SOD1 were performed using primers as described in the previous publication.The PCR products were directly sequenced.Results A heterozygous mutation H46R was found in four affected members in a family with middle age onset and slowly progressive ALS.A heterozygous mutation of G72C was identified in a 20-year-old male who died of respiratory failure after two years of ALS.His father carried the same mutation without clinical phenotype.In the third family with 20affected members with middle age onset and rapidly progress, a mutation of E13V was identified in 5 affected subjects.Conclusions This study is the first large screening of SOD1 mutation in Chinese familiar ALS patients.H46R has previously been found only in Japanese and Pakistanis; this is the first report in Chinese, suggesting H46R may be specific to Asians.The family with mutation G72C presented decreased penetrance, therefore screening SOD1 mutation in sporadic cases and unaffected family members is necessary.E133V is the first reported mutation and needs more study to investigate its effect on the disease.
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Objective to assess the utility of segmental motor nerve conduction study in differential diagnosis of chronic inflammatory demyelinating polyradiculoneuropathy(CIDP)and Charcot-Marie-Tooth type 1(CMT1).Methods A segmental motor nerve conduction study was performed on 16 patients with CIDP and 13 patients with CMT1.Distal motor latency,motor nerve conduction velocity,the changes of amplitude,area and duration of compound motor action potential over conventional segment were compared between the groups.ResultsDistal motor latency was (5.6±3.4) ms in CIDP and (9.3±2.1) ms in CMT1(t=5.347 P=0.000),motor nerve conduction velocity was (31.1±14.3) m/s in CIDP and(22.2±5.8)m/s(t=6.369,P=0.000),M50 of the decrease in amplitude over conventional segment was 29.7% in CIDP and 4.9% in CMT1 (Z=7.141,P=0.000).Distal motor latency was normal in 40.3% (25/62) nerves and motor nerve conduction velocity was normal in 18.1% (26/44)of segments in CIDP,while distal motor latency and motor nerve conduction velocity were abnormal in all nerves in CMT1.Motor nerve conduction block or abnormal temporal dispersion was detected in 29.2% segments in CIDP and 3.0% in CMT1 (x2=20.829,P=0.000).Conclusions The segmental motor nerve conduction study can help separate CIDP and CMT1.When motor nerve conduction block or abnormal temporal dispersion is detected,the motor nerve conduction velocity is distinctly various in different segments,the diagnosis of CIDP but not CMT1 should be considered.
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Objective To assess the utility of single fiber electromyography (SFEMG) in the differential diagnosis of amyotrophic lateral sclerosis (ALS) and cervical spondylotic radiculopathy and myelopathy. Methods SFEMG was performed in extensor digitorum communis muscles (EDC) of 3 groups of patients, including 61 ALS patients with findings of cervical spendylosis on MRI, 59 ALS patients with normal MRI of cervical spine, and 55 patients with cervical spendylotic radiculopathy and myelopathy. The parameters of SFEMG between different groups were compared. Results The mean jitter was (81.2± 25.9), (91.6 ± 32. 4) and (40. 9 ± 11.8) μ in ALS patients with finding of cervical spondylosis on MRI, ALS patients with normal MRI of cervical spine, and patients with cervical spondylosis respectively. M50 of the percentage of jitter >55 μs was 73%, 80% and 5% in the 3 groups respectively. M50 of the percentage of block was 10%, 20% and 0 in the 3 groups respectively. Fiber density was 2.9±0.5, 2.9±0.6 and 2. 4 ± 0. 6 in the 3 groups respectively. There was no significant difference in those parameters of SFEMG between the ALS with findings of cervical spondysosis and those with normal MRI. There was significant difference in those parameters of SFEMG between the patients with ALS (the mean jitter: (86. 3± 29. 6) μs; M50 of the percentage of jitter > 55 μs: 80% ; M50 of the percentage of block: 14% ; fiber density: 2. 9±0. 5) and those with cervical spondylosis (t = 14.49, Z = 8.96, 7. 68,t = 5. 83, all P = 0. 000). In 18 patients with ALS, conventional EMG studies showed active and chronic denervation in only 1 region at the first visit. SFEMG was performed in EDC which had normal Medical Research Council Scale and EMG. SFEMG showed increased fiber density in 16 patients, increased jitter in 13 patients and impulse block in 6 patients. Conclusion SFEMG shows significantly increased jitter and block in ALS whether there is MRI findings of cervical spondysosis or not, which can help to differentiate ALS from cervical spondysotic radiculopathy and myelopathy.
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Objective To investigate whether the polymorphism of rs10260404 in DPP6 gene in Chinese Han origin is associated with sporadic amyotrophic lateral sclerosis (SALS). Methods The genomic DNA was extracted from the leukocytes of whole blood samples in 58 Chinese Han patients with SALS and 52 healthy controls. The asymmetric PCR was processed in the presence of an unlabeled probe that contained the rs10260404 locus. The product was genotyped on light scanner and some was confirmed with sequencing. Results Two single nucleotide polymorphism, rs10260404 that was reportedly consistently strongly associated with susceptibility to SALS in different populations of European and American ancestry, rs10260404 were genotyped, but not strongly associated with ALS in Chinese patients(SALS:C:12.94%,T:87.06%;health controls:C:10.58%,T:89.43%;χ2=0.29,OR=1.256,95%CI 0.549-2.872, P>0.05). Conclusion The rs10260404 is not associated with ALS susceptibility in Chinese people.
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Objective To assess the diagnostic value of single fiber electromyography(SFEMG)in amyotrophic lateral sclerosis(ALS).Methotis SFEMG was performed in extensor digitorum communis muscles(EDC)of 165 patients with AIS and 145 patients with other neurogenetic disorders.Grade scale of the medical research council(MRC)in EDC was assessed simultaneously.The patients were divided into four groups according to the MRC scale(MRC＞4 us MRC≤4)and different disease (AIS vs other neurogenetic disorders).The parameters of SFEMG between different groups were compared.Results When the strength of EDC was normal(MRC＞4),the mean jitter was(66.1±20.1)μs in ALS and (38.0±9.2)μs in other neurogenic disorders(t=9.05,P＜0.01),median of the percentage of jitter＞ 55μs was 55%in AIS and 0 in other neurogenic disorders(Z=-7.81.P＜0.01).median of the percentage of block was 6.7%in AIS and 0 in other neurogenic disorders(Z=-6.93,P＜0.01).There was significant difference in those parameters of SFEMG between the two groups.When the strength of EDC was abnormal(MRC≤4),the mean jitter was(93.5±31.2)μs in ALS and(52.8±25.9)μs in other neurogenic disorders(t=9.37,P＜0.01),median of the percentage of jitter＞55 μs was 86%in ALS and 20%in other neurogenic disorders(Z=-8.46,P＜0.01),median of the percentage of block was 20%in ALS and 0 in other neurogenic disorders(Z=-7.25,P＜0.01).There was significant difference in those parameters of SFEMG between the two groups.When SFEMG was performed in EDC with normal muscle strength,the sensitivity and specificity of mean jitter＞55μs for diagnosis of ALS were 70.2%and 92.7% respectively.Conclusions When SFEMG is studied for diagnosis of ALS,it is recommended to perform in muscles with normal strength.The mean jitter,the percentage of jitter＞55μ s and block are of great importance in differentiating ALS from other neurogenic disorders.
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Objective To evaluate denervation changes [fibrillation potentials (fib) and positive sharp waves (psw)] in thoracic paraspinal muscles as diagnostic aids in amyotrophic lateral sclerosis (ALS). Methods The fib and psw of thoracic paraspinal muscles,the motor unit potential of sternocleidomastoid muscle were detected in 50 patients who had been identified as having ALS.Age and sex-matched,30 normal subjects and 30 patients who suffered radicular disease in cervical or lumbosacral region were also detected in thoracic paraspinal muscles for finding fib and psw serving as controls. Results In ALS group,a vast of fib and psw were found in thoracic paraspinal muscles in 41 of 50 ALS patients (82%),they were not found with sternocleidomastoid muscle,but the motor unit potential of this muscle was shown having long-duration and high-amplitude in 48 of 50 ALS patients (96%),which were coincided with the chronic neurogenic changes.6 of 50 patients had denervation changes of tongue muscles,3 of them found fib and psw.2 of 30 patients who suffered from radicular diseases were found with a few of fib and psw changes in thoracic paraspinal muscles.None of these symptoms were found in normal subjects.Conclusion A vast of fib and psw in thoracic paraspinal muscles should represent a sensitive tool for diagnosis of ALS.