bluuebunny/crossref_metadata_2025 huggingface dataset:
Active muscle length reduction progressively damages soleus in hindlimb‐suspended rabbits
Authors: Sancesario Giuseppe , Massa Roberto , Anzil Archinto P. , Bernardi Giorgio
Published: January 2005

This study describes the morphologic changes in rabbit soleus muscle following hindlimb suspension (HS) for 1 to 4 weeks (group A); or following HS with hindfeet passively dorsiflexed, by means of an elastic band, for 1 to 2 weeks (group B). In the latter, elastic band use allowed phasic contractions of foot extensor muscles against resistance and prevented 35% chronic soleus shortening, which occurred in group A animals. In group A, the soleus revealed progressive muscle atrophy and myofibrillar damage. Myofibrils underwent dissolution, muscle regeneration was ineffective, and adipose tissue developed from about 2‐week suspension onward. Conversely, passive dorsiflexon of unloaded hindfeet was essential in maintaining mass and structural muscle integrity in the soleus of group B. It is hereby demonstrated that HS‐induced soleus damage in the rabbit is progressive, and can be prevented, avoiding long‐term shortening of soleus and its phasic unloaded contractions, Soleus sensitivity to unloading conditions, such as HS, tenotomy, and hypogravity, may depend on the particular physiology of this tonic antigravity muscle, engaged mainly in developing long‐lasting isometric contractions in a strectched lenth. © 1992 John Wiley & Sons, Inc.
Improvement of the exercise test after therapy in thyrotoxic periodic paralysis
Authors: Jackson Carlayne E. , Barohn Richard J.
Published: January 2005

The diagnosis of periodic paralysis (PP) can be aided by demonstrating a decrease in compound motor action potential (CMAP) amplitude after several minutes of exercise. We report a case of secondary hypokalemic PP due to thyrotoxicosis in which the decrease in the CMAP amplitude after exercise dramatically improved after treatment, when a euthyroid state was achieved. The exercise test is a useful electropghysiologic means of monitoring the neuromuscular status of patients with thyrotoxic periodic paralysis prior to, and after treatment of the thyrotoxicosis.
AAEM minimonograph #13: H reflexes and F waves: Physiology and clinical indications
Authors: Fisher Morris A.
Published: January 2005

Motoneurons can be activated both reflexly and antidromically following electrical stimulation of peripheral nerves. These H reflexes and F waves are clinically useful responses which interface at the level of the peripheral nerves and the spinal cord. Because these responses are commonly employed in the electrodiagnostic evaluation of patients, an understanding of their physiology and clinical applications is important. These are reviewed. Reasoning from the physiology, both the value and limitations of H‐reflex and F‐wave studies are considered for disorders of peripheral nerves, roots, and the central nervous system. Theoretical concepts about the physiology and pathophysiology of the nervous system based on H‐reflex and F‐wave data are also discussed. © 1992 John Wiley & Sons, Inc.
Surface EMG in the recording of fasciculations
Authors: Howard Robin S. , Murray Nicholas M. F.
Published: January 2005

The usefulness of multichannel surface recording of fasciculations was evaluated by a retrospective study of 116 patients with various neurological disorders. Eight channels of a conventional electroencephalograph were used with plate electrode recordings from the upper arms and legs. Widespread fasciculations (defined as five or more of the eight muscle groups) were recorded in 48 of 54 patients with motor neuron disease, spinal muscular atrophy or postpolio syndrome, but noted on routine clinical examination at presentation in only 6. Eleven of 23 patients with peripheral neuropathy or myelopathy had fasciculations in five or more leads compared to one clinically, and 3 of 39 with other neurological diseases had fasciculations electrically but in only one were they clincally observed. The method is a noninvasive and sensitive adjunct to clinical examination for detecting fasciculations. Its diagnostic value is limited by the relatively high incidence of fasciculations in neuropathies and myelopathies. However, this study suggests that “false negatives” are rare and that the diagnosis of motor neuron disease should be reconsidered when less than five leads shows fasciculations. © 1992 John Wiley & Sons, Inc.
Lumbrical and interossei recording in carpal tunnel syndrome
Authors: Preston David C. , Logigian Eric L.
Published: January 2005

Median motor studies are commonly “normal” in mild carpal tunnel syndrome (CTS). This reflects either the sparing of motor compared to sensory fibers, or the inability of conventional studies to detect an abnormality. A novel approach to demonstrate early motor fiber involvement in CTS is the placement of the same active electrode lateral to the third metacarpal, allowing recording from the second lumbrical or the deeper interossei, when stimulating the median or ulnar nerves at the wrist, respectively. We compared the difference between these latencies in 51 normal control hands to 107 consecutive patient hands referred with symptoms and signs suggestive of CTS, who were subsequently proven to have electrophysiologic CTS by standard nerve conduction criteria. A prolonged lumbrical—interossei latency difference ( > 0.4 ms) was found to be a sensitive indicator of CTS in all patient groups. It was also helpful in patients with coexistent polyneuropathy, where localization at the wrist was otherwise difficult. © 1992 John Wiley & Sons, Inc.
Differential effects of amitriptyline on sudomotor, cardiovagal, and adrenergic function in human subjects
Authors: Low Phillip A. , Opfer‐Gehrking Tonette L.
Published: January 2005

Tricyclic antidepressants, especially amitriptyline (AMI), are widely used by patients who require tests of autonomic function. AMI effects autonomic function, but its quantitative and differential effects are not known. We prospectively evaluated the effect of AMI on sudomotor (M3 receptor), cardiovagal (M2) and adrenergic functions in 6 subjects, aged 20‐40 years before, during, and 48 hours after AMI 75 mg/d. M3 receptor function was evaluated using QSART (quantitative sudomotor axon reflex test) recordings from four sites, M2 receptor function from cardiovagal studies [HR response to deep breathing (HRDB) and the Valsalva ratio (VR)], and adrenergic function from an analysis of beat‐to‐beat BP responses to tilt and the Valsalva maneuver. Plasma AMI was determined from blood samples obtained within 2 hours of autonomic testing. QSART volume was reduced by 47% by AMI (P = 0.01), and recovered to 81% of baseline following a 48‐hour washout. HRDB was unaffected by AMI (P > 0.05). VR was increased by 10% (NS) with AMI and by 14% (P ≤ 0.05) with washout. The percent change in hemodynamic parameters by AMI were: orthostatic reduction in SBP, 62% (NS); orthostatic HR increment, 66%, (P = 0.03); and phase IIe SBP decrement, 665%, (P = 0.02). We conclude that AMI in the moderate doses used, resulted in greater inhibition of M3 than M2 receptors. The BP, HR, and beat‐to‐beat BP alterations likely reflect adrenergic inhibition resulting in a reduction in effective plasma volume. A washout of 48 hours is adequate for muscarinic but not adrenoreceptors. © 1992 John Wiley & Sons, Inc.
The silent period in pure sensory neuronopathy
Authors: Leis A. Arturo , Kofler Markus , Ross Mark A.
Published: January 2005

“Normal” electromyographic silent periods (SPs), produced by electrical stimulation of digital nerves, were recorded in the voluntarily contracting abductor pollicis brevis (APB) muscle of a patient with pure sensory neuronopathy and absent sensory nerve action potentials (SNAPs). Such findings implicate the smaller, slower conducting fibers in the genesis of the cutaneous silent period. These same fibers may be activated during more proximal stimulation to contribute to the latter portions of the mixed nerve silent period. © 1992 John Wiley & Sons, Inc.
Effect of caffeine and high potassium on normal and dystrophic mouse EDL muscles at various developmental stages
Authors: Dangain Josette , Neering Ian R.
Published: January 2005

EDL muscles from normal and dystrophic (dy2j) mice of various ages were examined. Muscles were divided into three groups according to age: 7 to 14 days postnatal, 16 to 21 days postnatal, and 6 months old, to assess age and/or phenotype related differences in the muscle response to caffeine or high K+. The response of normal muscles to caffeine decreased with age and reached adult characteristics between the second and third week of postnatal life. Their response to high K+ also changed during post‐natal development; specifically, the time taken to recover to 50% pretest twitch tension decreased with age, probably reflecting developmental changes in Cl− conductance. Up to 21 days of age, the sensitivity of dystrophic muscles to both caffeine and high K+ was essentially similar to normal, while marked differences were observed in the adult. Taken altogether, our results suggest that while the maturation of a number of systems might be delayed in dystrophic muscles at preclinical stages of the disease, their e–c coupling and SR function (Ca2+ release and reuptake) appear to be quite normal. Our results further suggest that the “abnormal” responses of dystrophic muscles at more advanced stages of the disease, when challenged by drugs acting on either of these systems, may be explained in terms of changes in muscle fiber type proportions. © 1993 John Wiley & Sons, Inc.
Progressive unilateral hypertrophic myopathy: A case study
Authors: Pihko Helena , Lehtinen Ilkka , Tikkanen Heikki , Härkönen Matti , Rapola Juhani , Lamminen Antti , Sahlman Antero , Somer Hannu
Published: January 2005

A 12‐year‐old girl had progressive unilateral muscle hypertrophy limited to the sole, tibialis anterior, and biceps femoris muscles. The affected muscles showed complex repetitive discharges by electromyography, necrosis and variation of fiber size upon histopathological examination, and increased metabolic activity in biochemical studies. The findings suggest a myopathic origin, but the actual cause remains unknown. © 1993 John Wiley & Sons, Inc.
HTLV‐1 in acquired adult myopathy
Authors: Dickoff David J. , Simpson David M. , Wiley Clayton A. , Mendelson Stuart G. , Farraye Joseph , Wolfe David E. , Wachsman William
Published: January 2005

We report a 53‐year‐old Jamaican man with 20 years of progressing weakness involving proximal limb muscles and neck flexors. Serum CK was 1100 IU/L. EMG demonstrated spontaneous activity, myopathic motor units, and full recruitment patterns in weak muscles. Muscle biopsy revealed marked myofiber degeneration with extensive fibrosis, suggesting a chronic myopathic process. HTLV‐1 antibody was present in serum in high titers by ELISA and Western blot. Immunohistochemistry with rabbit polyclonal antisera to HTLV‐1 showed rare staining myocytes. PCR demonstrated HTLV‐1 DNA in frozen muscle tissue. This myopathy, associated with HTLV‐1 infection, has clincal and pathological features similar to a dystrophy. We recommend serological screening for HTLV‐1 in cryptogenic adult myopathies. © 1993 John Wiley & Sons, Inc.
Acoustic myography compared to electromyography during isometric fatigue and recovery
Authors: Rodriquez Arthur A. , Agre James C. , Knudtson Eileen R. , Cota  , Franke Todd M. , Ng Alexander V.
Published: January 2005

This study compared the acoustic (RMS‐AMG) to electromyographic (RMS‐EMG) signal, median frequency of EMG power spectrum (Fm), and quadriceps torque during isometric fatiguing contraction (FC) and recovery. Seven subjects were tested for strength (MVC) and then, on separate days, maintained 20%, 40%, or 80% MVC to exhaustion followed by MVC testing at regular intervals. Throughout FC, RMS‐EMG significantly (P < 0.05) increased and Fm significantly (P < 0.05) decreased during all trials; RMS‐AMG significantly (P < 0.05) increased only during the 20% and 40% trials. During recovery, MVC and RMS‐EMG recovered most slowly after the 20% trial and most rapidly after the 80% trial; Fm and RMS‐AMG recovered by 90 seconds after all trials. RMS‐AMG reflects RMS‐EMG during low but not high levels of FC. Recovery of strength is most depressed following FC at lower relative levels of torque. We conclude that RMS‐AMG behaves differently than RMS‐EMG, torque, and Fm during FC and recovery. © 1993 John Wiley & Sons, Inc.
Reduced capability of transmitting high frequency impulses in tail nerves of diabetic rats
Authors: Nielsen J. F. , Andersen H. , Nielsen V. K.
Published: January 2005

The effect of long‐term (40 min) high frequency stimulation (143 Hz) of sensory‐motor tail nerves was studied in normal and in streptozotocindiabetic rats. The study comprised a 6‐week period, repeating the test at 2‐week intervals. In the initial (prediabetic) study, single experiments showed a mild depression of the peak‐to‐peak ampltiude during high frequency stimulation, which reversed completely during a subsequent rest period. In normal rats, the amplitude depression was unchanged in repeated tests over a 6‐week period. Diabetic rats showed a greater amplitude depression during high frequency stimulation. The difference was statistically significant after 2 weeks, but showed no further change at subsequent tests. The greater decrease in the amplitude in diabetic rats may reflect a depression of the axon membrane function, which may be the functionl correlate to the inhibition of the Na/K ATPase activity in diabetes, described by others. Monitoring of the axon membrane functional capacity may have clinical implications in the control of peripheral neuropathies. © 1993 John Wiley & Sons, Inc.
α‐Bungarotoxin sensitization in experimental autoimmune myasthenia gravis
Authors: Kennel Philippe F. , Poindron Philippe , Warter Jean‐Marie , Fonteneau Paul
Published: January 2005

A mouse model of MG, termed experimental autoimmune myasthenia gravis (EAMG), can be obtained after immunization with Torpedo acetylcholine receptor (AChR). Although many studies have detailed the consequence of AChR antibodies binding at the neuromuscular junction and the difficulty in obtaining obvious clinical signs, less attention has been focused on the possibility of amplifying the muscular block in order to discriminate between immunized and healthy animals. In the present studies we observe that a single inoculation of α‐bungarotoxin (α‐bgt) can amplify the neuromuscular block revealed by repetitive nerve stimulation, and induce in EAMG mice a stable muscular weakness state lasting for at least 169 hours instead of 95 hours in normal mice. This model could provide an excellent tool for evaluating drugs active on neuromuscular transmission. © 1993 John Wiley & Soncs, Inc.
KANDID–an EMG decision support system–evaluated in a European multicenter trial
Authors: Vingtoft Søren , Fuglsang‐Frederiksen Anders , Rønager Jesper , Petrera Jorge , Stigsby Bent , Willison Robin G. , Jarratt John A. , Fawcett Peter R. W. , Schofield Ian S. , Otte George , Sieben Guido , Vila Annick
Published: January 2005

KANDID is an advanced EMG decision support system dedicated to the support of the clinical neurophysiologist during EMG examinations. It has facilities for test planning, automatized and structured data interpretation, EMG diagnosis, explanation, and reporting. In a prospective European multicenter field trial, the agreement levels between clinical neurophysiologists and KANDID's diagnostic statements were measured under ordinary clinical EMG practice. KANDID was assessed in 159 individual patient EMG examinations by nine clinical neurophysiologists at seven different EMG laboratories. The reasoning of KANDID was considered understandable for the examiners in 80–90% of cases. The agreement level for the electrophysiological states of muscles and nerves between KANDID and the individual examiners was, on average, 81%. The corresponding diagnostic agreement with KANDID was, on average, 61%. A pronounced interexaminer variation in the agreement level related to the different EMG centers was observed. All Danish and Belgian examiners agreed with KANDID in more than 50% of their cases with regard to the EMG diagnosis, while the English examiners were in agreement with KANDID in 50% or less of their cases. These differences were possibly due to differences in epidemiology, examination techniques, control material, and examination planning strategies. It is concluded that it is possible to transfer systems like KANDID out of their development sites and apply them successfully if they can be locally customized by the clinical end users via editors. © 1993 John Wiley & Soncs, Inc.
Muscle glucose‐6‐phosphate dehydrogenase deficiency: Restoration of enzymatic activity in hybrid myotubes
Authors: Meola Giovanni , Tremblay Jacques P. , Sansone Valeria , Rotondo, Giuseppe , Radice Stefania , Bresolin Nereo , Huard Johnny , Scarlato Guglielmo
Published: January 2005

A high level of glucose‐6‐phosphate dehydrogenase (G6PD) activity was observed in myoblasts and myotubes from normal human and mouse cell cultures. However, only a residual amount of activity was observed in myoblasts and myotubes obtained from G6PD‐deficient patients (G6PD Mediterranean). Hybrids were formed by the fusion of normal (from human and mouse) and G6PD‐deficient myoblasts (from the patients). These hybrids contained a high level of G6PD activity. Hoechst staining permitted to confirm that the enzymatic activity was not restrained to a domain near the competent nuclei. These results suggest that myoblast transplantation could be used to restore normal enzymatic activity in metabolic myopathies.
Recombinant growth hormone treatment of amyotrophic lateral sclerosis
Authors: Smith R. A. , Melmed S. , Sherman B. , France J. , Munsat T. L. , Festoff B. W.
Published: January 2005

Based on the known trophic effects of growth hormone (GH) on nerve and muscle 75 patients with ALS were treated for up to 18 months with synthetic human growth hormone (Protropin) or a placebo. The course of ALS was assessed serially using a quantitative (TQNE) neuromuscular and manual exam (MRC) and laboratory chemistries. Average insulin‐related growth factor (IGF‐1) values increased from 1.2 to 2.3 U/mL in the treated group. Surprisingly, serum insulin levels did not increase. Hyperglycemia was noted in only 2 patients of the 38 patients receiving hGH, and this resolved with cessation of treatment. Over the 12 months of treatment there were 11 deaths (6 controls, 5 treated). Survival analysis, performed approximately 12 months following cessation of treatment, did not reveal a difference between the treatment and placebo group. The TQNE scores declined inexorably in both the control and treated group. Retrospective analysis of the TQNE data indicate a poor prognosis for patients who lost arm strength early. A correlation between the TQNE and MRC scores was evident at early stages of motor unit loss, less so when muscle weakness was advanced. © 1993 John Wiley & Sons, Inc.
A comparison of electric and magnetic compound action signals as quantitative assays of peripheralo nerve regeneration
Authors: Kuypers Paul D. L. , Gielen Frans L. H. , Wai Ruud Tjong Joe , Hovius Steven E. R. , Godschalk Moshe , van Egeraat Jan M.
Published: January 2005

The evaluation of peripheral nerve regeneration is of great interest in clinical as well as in experimental situations. However, there are few techniques that give early and quantitative information on the states of the regeneration process. If quantitative assays would be available, different surgical techniques and medications could be evaluated more accurately in relation to axonal ingrowth and functional recovery. The purpose of this study was to investigate the merits of nerve compound action signals (NCASs) recorded electrically and signals recorded with a novel magnetic recording technique. We compared the two techniques in the rabbit peroneal nerve, 2, 4, 6, and 8 weeks after a nerve reconstruction. Our conclusions are that the signals recorded with the magnetic sensor are far more reproducible and less prone to stimulus artifact than the electrically recorded signals. Furthermore, the magnetic recording shows that the number of axons that have regenerated increases with time. Previously, this could only be determined with histological studies. Other ingrowth parameters that can be quantified are the average ingrowth distance, and the variation between axons in ingrowth velocity. © 1993 John Wiley & Sons, Inc.
Invited review: Microneurography and applications to issues of motor control: Fifth annual stuart reiner memorial lecture
Authors: Hagbarth Karl‐Erik
Published: January 2005

Among the hypotheses regarding fusimotor functions based on earlier animal experiments some are inconsistent, others are in conformity with microneurographic observations in man. The human data provide evidence against the following two theories: (1) the length follow‐up servo theory; and (2) the theory that fusimotor neurons can be selectively activated to produce spindle sensitization and stretch reflex reinforcements. The human data support the theory of alpha–gamma coactivation. In particular, in the early phase of isometric voluntary contractions fusimotor‐driven afferent spindle activity assists in autogenetic activation of alpha motoneurons and in reciprocal relaxation of antagonists. As muscle fatigue develops, the autogenetic reflex drive via the fusimotor route declines. The fusimotor bias during contraction provides for maintenance of spindle sensitivity to minute perturbations and for load‐compensating reflex adjustments to such perturbations. Reflex overcorrections may lead to uncontrollable oscillations of the type seen in enhanced physiological tremor.
AAEM case report #27: Acute retrohumeral radial neuropathies
Authors: Brown William F. , Watson Bradley V.
Published: January 2005

AAEM case report #27. Acute radial neuropathies localized to the retrohumeral course of the radial nerve are common. Most individuals fully recover within a matter of days or, at the most, a few weeks. In a few, recovery may take longer and occasionally remains incomplete. In almost all instances the site of injury to the radial nerve can be accurately localized to the region of the spiral groove and the relative contributions of conduction block and axonal degeneration assessed using electrophysiologic techniques.
Primary respiratory failure as the presenting symptom in Lambert–Eaton myasthenic syndrome
Authors: William C. , Claussen Gwen , Thomas Darryl , Fesenmeier James T. , Pearlman Robert L. , Oh Shin J.
Published: January 2005

Myasthenia gravis can present with rapid respiratory failure as the first manifestation of disease. In the Lambert–Eaton myasthenic syndrome (LEMS), such a manifestation has rarely been reported. We are reporting a patient who developed respiratory failure as the first manifestation of LEMS without associated carcinoma.
Far‐field potentials in cylindrical and rectangular volume conductors
Authors: Dumitru Daniel , King John C. , Rogers William E.
Published: January 2005

The occurrence of a transient dipole is one method of producing a far‐field potential. This investigation qualitatively defines the characteristics of the near‐field and far‐field electrical potentials produced by a transient dipole in both cylindrical and rectangular volume conductors. Most body segments of electrophysiologic interest such as arms, legs, thorax, and neck are roughly cylindrical in shape. A centrally located dipole generator produces a nonzero equipotential region which is found to occur along the cylindrical wall at a distance from the dipole of approximately 1.4 times the cylinder's radius and 1.9 times the cylinder's radius for the center of the cylinder. This distance to the equipotential zone along the surface wall expands but remains less than 3.0 times the cylindrical radius when the dipole is eccentrically placed. The magnitude of the equipotential region resulting from an asymmetrically placed dipole remains identical to that when the dipole is centrally located. This behavior is found to be very similar in rectangular shallow conducting volumes that model a longitudinal slice of the cylinder, thus allowing a simple experimental model of the cylinder to be utilized. Amplitudes of the equipotential region are inversely proportional to the cylindrical or rectangular volume's cross‐sectional area at the location of dipolar imbalance. This study predicts that referential electrode montages, when placed at 3.0 times the radius or greater from a dipolar axially aligned far‐field generator in cylindrical homogeneous volume conductors, will record only equipotential far‐field effects.
Muscle carnitine deficiency and lipid storage myopathy in patients with mitochondrial myopathy
Authors: Campos Yolanda , Huertas Rosa , Bautista Juan , Gutierrez Eduardo , Aparicio Manuel , Lorenzo Gustavo , Segura Dolores , Villanueva Mercedes , Cabello Ana , Alesso Luis , Arenas Joaquin
Published: January 2005

Abnormal carnitine distribution in muscle was found in 22 of 77 patients (29%), with mitochondrial myopathy. Furthermore, total (TC) and free (FC) carnitine levels in muscle were lower in patients than in controls (P < 0.01). Muscle long‐chain acylcarnitines (LCAC) were significantly increased in these patients (P < 0.01). Muscle carnitine deficiency was found in 31.5% of patients with lipid storage myopathy (LSM) and in 25.6% of patients with ragged‐red fibers (RRF). Therefore, carnitine deficiency can be found in patients with mitochondrial myopathy even in the absence of LSM. Muscle levels of TC and FC were lower in patients with respiratory chain defects than in those with normal respiratory chain (P < 0.01). In contrast, LCAC levels were significantly increased (P < 0.05). Carnitine levels did not differ significantly, among patients with different respiratory‐chain defects. Consequently, these patients, owing to their biochemical block, reduce progressively the muscle carnitine pool and subsequent LCAC rise, due to long‐chain fatty acid (LCFA) accumulation.
Modification of the peripheral nerve disturbance in ciguatera poisoning in rats with lidocaine
Authors: Cameron John , Flowers Andrew E. , Capra Michael F.
Published: January 2005

Electrophysiological studies were performed on the ventral tail nerve of adult rats following intraperitoneal injection of a crude extract of ciguatoxin from known toxic fish flesh. Ciguatoxin induced significant slowing of both mixed and motor nerve conduction velocities and also significant reductions in both motor and mixed nerve amplitudes. Both absolute and supernormal periods were significantly prolonged together with an increase in the magnitude of the supernormal response. These electrophysiological disturbances were modified or blocked by intraperitoneal lidocaine. These findings suggest that lidocaine may have a potential therapeutic application in the treatment of the neurological disturbance in acute ciguatera poisoning in humans.
Magnetic stimulation: C‐8 root standardization based on arm length and arm position
Authors: Tamler Martin S. , Siegel Cara B.
Published: January 2005

Normal values for C‐8 root distal latencies (DL) by magnetic stimulation (Magstim) have been reported; however, the methods of standardization have failed to consider the variables of arm length and arm position. Consequently, an artificial widening of the “normal” range occurs due to a false elevation of the standard deviation. In this study, Magstim of the C‐8 nerve root was performed on 30 normal volunteers. Gender, hand temperature, age, arm length, and DL with the arm resting at the patien's side and fully abducted were recorded. DL was 13.3 ± 1.1 ms with a side‐to‐side variation of 0.3 ± 0.3 ms. The difference in DL between the arm at rest and in full abduction was 0.2 ± 0.3 ms. Data analysis also demonstrated a direct correlation between arm length and DL. Utilizing this information a formula has been derived to more accurately describe the normal distribution of the C‐8 root DL by Magstim. © 1993 John Wiley & Sons, Inc.
Effect of myasthenic IgG on degradation of junctional acetylcholine receptor
Authors: Takeo Gou , Motomura Masakatsu , Matsuo Hidenori , Ohishi Kiyosumi , Yoshimura Toshiro , Nagataki Shigenobu , Tsujihata Mitsuhiro
Published: January 2005

We investigated the effect of the lgG from patients with myasthenia gravis (MG) on the degradation of normal rat junctional acetylcholine receptor (AChR) labeled with 125l‐α‐bungarotoxin (BuTx) and calculated the degradation rate (DR). The DR for the lgG from these patients was significantly higher than that from healthy volunteers and patients with other autoimmune diseases. For MG, DR was significantly correlated with the severity of the disease but not with anti‐AChR antibody titer. DR was accelerated by lgG from patients with generalized MG whose antibody titers were in the normal range and by lgG from patients with ocular MG. These results indicate that measurement of the DR of junctional AChR in normal rats is more closely correlated with the severity of the disease than is measurement of anti‐AChR antibody and that the former is a sensitive and confirmatory method for evaluating MG. © 1993 John Wiley & Sons, Inc.
Femoral mononeuropathy induced by the lithotomy position: A report of 5 cases with a review of literature
Authors: Hakim Mazen Al , Katirji M. Bashar
Published: January 2005

We report 5 young women who developed femoral mononeuropathy (FMN) after placement in the lithotomy position. Three had uncomplicated vaginal deliveries and 2 underwent exploratory laparoscopies. EMG was performed on 3 patients. The lesions were localized to the inguinal ligament and probably demyelinating, accounting for their excellent prognosis. On reviewing the literature, however, we believe that lithotomy position can cause FMN, not only by nerve compression at the inguinal ligament, but also by stretching of the nerve by excessive hip abduction and external rotation. © 1993 John Wiley & Sons, Inc.
Issue & Opinions. Are nerve conduction studies useful for monitoring the adequacy of renal dialysis?
Authors: Phillips Lawrence H. , Williams Faren H.
Published: January 2005

When hemodialysis was first used clinically, a peripheral neuropathy frequently emerged. The discovery that sufficient dialysis time would prevent the emergence of symptomatic neuropathy led to the routine use of nerve conduction studies (NCS) to monitor the „adequacy”︁ of dialysis. Modern dialysis practice has evolved since then, and the patient populationis markedly different. This report addresses the question of whether there is evidence to indicate that routine use of NCS is helpful to monitor the adequacy of present‐day dialysis. A critical review of the available literature reveals that there is insufficient evidence to allow one to answer the question. © 1993 John Wiley & Sons, Inc.
The human sensory unit and pain: New concepts, syndromes, and tests
Authors: Ochoa José L.
Published: January 2005

This is an overview on aspects of structure, function and pathology of the primary sensory unit in man, emphasizing concepts which form the basis for understanding the nature of neuropathic sensory syndromes and the rationale for special clinical physiologic testing. © 1993 John Wiley & Sons, Inc.
Central pain: “new” syndromes and their evaluation
Authors: Berić Aleksandar
Published: January 2005

Central pain syndrome is defined as pain associated with a lesion of the central nervous system. It has a low incidence but is frequently intractable and does not have effective treatment. The cause of central pain is speculative; however, the single common sensory abnormality in patients with central pain is interruption of spinothalamocortical nociceptive pathways. It appears that severe central nervous system lesions, with total destruction of ascending sensory systems, do not lead to a central pain syndrome; and that setting of mild, moderate, or severe disruption of the anterolateral ascending system with partial or complete preservation of the dorsal column/medial lemniscus functions is most frequently associated with central pain syndrome. Furthermore, even during remission, dysesthesias and pain could be triggered by additional afferent input to the large fiber/dorsal column/medial lemniscus system and, once established, they may not be abolished byadditional deafferentation. © 1993 John Wiley & Sons, Inc.
Pediatric peroneal mononeuropathy: A clinical and electromyographic study
Authors: Jones H. Royden , Felice Kevin J. , Gross Paul T.
Published: January 2005

Seventeen children with pediatric peroneal mononeuropathies evaluated between 1979 and 1991 are reported. Twelve boys and 5 girls, ranging in age from 1.5 months to 17 years, were referred for footdrop in 16 children (94%) or for lower extremity pain in 1 child (6%). Causes included compression in 10 children (59%), trauma in 3 children (18%), entrapment in 3 children (18%), and indeterminate in 1 child (5%). Based on nerve conduction studies and electromyography, the level of the pediatric peroneal mononeuropathic lesion was the common peroneal nerve in 10 children (59%), the deep peroneal nerve in 2 children (12%), and the superficial peroneal nerve in 1 child (5%). In 4 other children (24%), pediatric peroneal mononeuropathy at the knee was not more precisely identified. Surgical exploration in 3 children with progressive pediatric peroneal mononeuropathy was valuable. Improvement occurred in 13 of 17 children (76%). © 1993 John Wiley & Sons, Inc.
Selective deep peroneal nerve injury associated with arthroscopic knee surgery
Authors: Esselman Peter C. , Tomski Mark A. , Robinson Lawrence R. , Zisfein James , Marks Stephen J.
Published: January 2005

We report 3 cases of isolated deep peroneal nerve injury as a complication of arthroscopic knee surgery. At the level of the knee joint, the deep and superficial peroneal nerves are usually joined as the common peroneal nerve. However, because of the fascicular structure, a partial nerve injury can result in an isolated injury to the deep peroneal nerve fibers. Due to the intraneural topography of the peroneal nerve, electrodiagnostic studies in a partial nerve injury may erroneously indicate a more distal lesion. © 1993 John Wiley & Sons, Inc.
Neuromuscular transmission in amyotrophic lateral sclerosis
Authors: Maselli Ricardo A. , Wollman Robert L. , Leung Cynthia , Distad Barbara , Palombi Sandra , Richman David P. , Salazar‐Grueso Edgar F. , Roos Raymond P.
Published: January 2005

The functional and structural characteristics of the neuromuscular junction were studied in anconeus muscle biopsies of 10 patients with amyotrophic lateral sclerosis (ALS). Intracellular recordings revealed decreased amplitudes of miniature endplate potentials (MEPPs). The MEPP frequencies were highly variable in ALS patients but the average MEPP frequency was not different from that of control patients. The mean quantal content of endplate potentials (m), the mean quanta available for immediate release (n), and the mean quantal stores (N) were all decreased. In contrast, the mean probability of quantal release (p) was normal and the mean probability of quantal store release (P) was surprisingly high at the majority of ALS endplates. Histologic evidence of denervation and small or absent nerve terminals were observed in all ALS patients. These functional and structural abnormalities of the neuromuscular junction may explain the fatigability and the electromyographic evidence of impaired neuromuscular transmission often encountered in ALS patients. © 1993 John Wiley & Sons, Inc.
Screening of dominantly inherited Charcot–Marie–Tooth neuropathies
Authors: Ionasescu Victor V. , Ionasescu Rebecca , Searby Charles
Published: January 2005

Sixty‐three families with dominantly inherited Charcot–Marie–Tooth (CMT) neuropathies including 730 subjects (total) from which 356 affected were studied clinically, electrophysiologically (MNCVs and EMGs), by genetic linkage, and screened for DNA duplication. Thirtyeight families (60.3%) were type 1A (demyelinating CMT mapped on chromosome 17). DNA duplication was present in 36 families (94.8% of CMT1A families). One CMT1A family (2.6%) showed no duplication but suggested genetic linkage with markers of chromosome 17. One CMT1A family (2.6%) revealed nonduplication in some affected members and duplication in other affected members. The disease in that family segregated with the same chromosome 17 markers regardless of duplication status. The other CMT families with dominant inheritance but without duplication included one family with CMT1B (demyelinating CMT mapped on chromosome 1) (1.6%), 14 families with CMT2 axonal neuropathy (22.2%), and 10 families with X‐linked dominant CMT (15.9%). © 1993 John Wiley & Sons, Inc.
Determinants of mean motor unit size: Impact on estimates of motor unit number
Authors: Doherty Timothy J. , Stashuk Daniel W. , Brown William F.
Published: January 2005

The purpose of this study was to compare two fundamentally different methods of deriving the average surface‐detected motor unit action potential (S‐MUAP) size from which to calculate a motor unit number estimate (MUNE), namely: (1) the simple arithmetic average of S‐MUAP parameter values; and (2) a computer‐derived datapoint by datapoint average waveform which takes account of differences in S‐MUAP shapes and durations. Multiple point stimulation was used to collect representative samples of between 11 and 20 S‐MUAPs (mean 15 ± 2 SD) from the median‐innervated thenar muscles of 20 healthy control subjects between 20 and 76 years of age (mean 48 ± 19 SD). The average S‐MUAP size based on peak‐to‐peak amplitude, negative peak amplitude, and negative peak area measurements was calculated using the two different methods. The mean S‐MUAP sizes based on the average waveform were significantly lower in all cases than those based on the simple average of S‐MUAP parameter values. Differences tended to be greatest for MUNEs based on peak‐to‐peak amplitude (35%), less for negative peak amplitude (20%), and least for negative peak area (16%). © 1993 John Wiley & Sons, Inc.
Emery‐Dreifuss muscular dystrophy with unusual features
Authors: Deymeer Feza , Öge A. Emre , Bayindir Çiçek , Kaymaz Cihangir , Nişanci Yilmaz , Adalet Kamil , Yates John R. W. , Ózdemir Coşkun
Published: January 2005

Two families with Emery‐Dreifuss muscular dystrophy (EMD) are described. Several unusual features for EMD are emphasized. One of the patients had severe neuromuscular disability with inability to walk during early childhood. This patient also had mild bifacial paresis. His brothers had the typical slow progression of EMD. In some of the patients, muscle weakness distribution was more widespread than has usually been reported, with prominent involvement of finger extensors. It is suggested that there is a wide phenotypic spectrum in EMD. In both families, the disease segregated with markers spanning the EMD locus in Xq28. © 1993 John Wiley & Sons, Inc.
Paraneoplastic pseudo‐obstruction, mononeuropathy multiplex, and sensory neuronopathy
Authors: Liang Bertrand C. , Albers James W. , Sima Anders A. F. , Nostrant Timothy T.
Published: January 2005

A patient with mononeuropathy multiplex, sensory neuronopathy, and diffuse intestinal pseudo‐obstruction consisting of gastroparesis and impaired small and large bowel motility was found to have a small cell carcinoma of the lung. The constellation of findings were indicative of paraneoplastic neuropathy, which was confirmed with the appropriate antibody studies demonstrating antineuronal nuclear antibodies. Identification of paraneoplastic neuropathy is important, since early treatment of the primary cancer, which is virtually always a small cell carcinoma of the lung, may halt the progression of the disorder. © 1994 John Wiley & Sons, Inc.
Electrophysiological characterization of pre‐ and postoperative facial nerve function in patients with acoustic neuroma using electrical and magnetic stimulation techniques
Authors: Rösler Kai M. , Jenni Walther K. , Schmid Urs D. , Hess Christian W.
Published: January 2005

Facial nerve function was examined in patients who underwent posterior fossa surgery for unilateral acoustic neuroma. Examinations took place prior to surgery (n = 47 patients), early after surgery (0–12 days, n = 16 of 47 patients), and late after surgery (187–1505 days, n = 29 of 47 patients). Clinical signs of facial palsy were present to a variable extent in 13 of 47 patients before, in 12 of 16 patients early, and in 18 of 29 patients later after surgery. Electrophysiologically, the facial nerve was stimulated electrically at the stylomastoid fossa and magnetically at its proximal intracanalicular segment. In addition, the faceassociated motor cortex was stimulated magnetically. In patients with facial palsy, any of these stimulation methods resulted in a decreased amplitude of the response in the nasalis muscle. The decrease showed a linear relationship to the clinical grade of palsy, pre‐ and postoperatively. Corticomuscular latencies remained unchanged. We conclude that: (i) the electrophysiological characteristics of facial nerve lesions due to compression by acoustic neuromas or due to a complication of neuroma removal are those of a purely axonal neuropathy; (ii) the three stimulation techniques have a similar diagnostic yield, thus making the use of all three of them redundant; and (iii) the electrophysiological techniques allowed no prediction of the final facial nerve function. © 1994 John Wiley & Sons, Inc.
Expression of utrophin (dystrophin‐related protein) and dystrophin‐associated glycoproteins in muscles from patients with Duchenne muscular dystrophy
Authors: Mizuno Yuji , Yoshida Mikiharu , Nonaka Ikuya , Hirai Shunsaku , Ozawa Eijiro
Published: January 2005

We examined whether the dystrophin‐associated glycoprotein complex (GPC), which serves to fix dystrophin to cell membranes, is present at the sarcolemma in Duchenne muscular dystrophy (DMD) muscles using an immunohistochemical method. Antibodies against 50DAG (A2) and 43DAG (A3a). the components of GPC, were used for the detection of GPC. We found that, although the amount of GPC was reduced in DMD muscles where ulrophin but not dystrophin was distinctly present, 43DAG (A3a) was fairly heavily and 50DAG (A2) was lightly but distinctly stained on the cell surfaces. It is likely that the capability of utrophin to preserve 50DAG (A2) is less than that of dystrophin, although utrophin has been reported to bind to GPC. We also found that 43DAG (A3a) but not 50DAG (A2) was detected in the peripheral nerves where utrophin was detected. Therefore, it is likely that 43DAG (A3a) is essential for the fixation of utrophin to cell membranes, as in the case of dystrophin. 50DAG (A2) may play other important roles in the pathogenesis of DMD. © 1994 John Wiley & Sons, Inc.
Neuropathy in familial amyloidosis, Finnish type (FAF): Electrophysiological studies
Authors: Kiuru Sari , Seppäläinen Anna‐Maria
Published: January 2005

We report, for the first time, electrophysiological findings in the Finnish type of familial amyloidosis (FAF), a gelsolin‐related form of systemic amyloidosis. Electromyography, nerve conduction studies, and blink reflex examinations were performed in 30 patients (age range 27–74 years). Cranial nerve involvement was detected in all, and peripheral nerve involvement in the majority of patients. Carpal tunnel syndrome was a characteristic feature of FAF, previously unrecognized. Myokymia‐type short spontaneous bursts in frontal muscles were found in 3 younger patients. In addition to signs of axonal degeneration we found slow nerve conduction, prolonged distal motor latencies, and conduction blocks suggestive of demyelination. Most nerve conduction velocities correlated remarkably with age. We conclude that FAF is characterized not only by distinct clinical and molecular biological features but also by electrophysiological findings, which enable differentiation from other hereditary amyloidoses. © 1994 John Wiley & Sons, Inc.
AAEM minimonograph #42: Intraoperative monitoring of peripheral and cranial nerves
Authors: Brown William F. , Veitch James
Published: January 2005

Intraoperative studies of focal neuropathies have become increasingly common both as an aid to the localization of the neuropathy and a means of monitoring the integrity of the nerve in the course of surgery. Success very often depends on careful attention to the technical problems presented by working in the operating theater. Despite these difficulties, assessment of conduction directly from the exposed nerve offers opportunities for better understanding the pathophysiology of these neuropathies and correlating these findings with conventional electrodiagnostic studies. © 1994 John Wiley & Sons, Inc.
Widenings of the myelin lamellae in a typical Guillain–Barré syndrome
Authors: Vallat J. M. , Leboutet M. J. , Jauberteau M. O. , Tabaraud F. , Couratier P. , Akani F.
Published: January 2005

The so‐called “widenings of the myelin lamellae” are thought to be specific ultrastructural features of peripheral nerve myelin in patients with peripheral neuropathy associated with a monoclonal dysglobulinemia of IgM type and antiglycolipid activity. We report here a case of Guillain–Barré syndrome with no evidence of serum monoclonal dysglobulinemia, presenting the typical widenings of the myelin lamellae in small‐diameter myelinated fibers from a sural nerve biopsy. In view of the positive reaction with anti‐C3d complement on direct immunofluorescence, an immunological mechanism may be involved in the widenings of the myelin lamellae. © 1994 John Wiley & Sons, Inc.
Submaximal stimuli activate different nerve fiber populations at different sites
Authors: Preston David C. , Venkatesh S. , Shefner J. M. , Logician E. L.
Published: January 2005

Theoretically, the largest and fastest nerve fibers are preferentially stimulated with submaximal stimuli. However, it is also well known that intraneural fascicular topography changes substantially along a proximal to distal axis. Because of this change in fascicular topography, we hypothesized that percutaneous submaximal stimuli applied to a nerve at different locations would stimulate different subpopulations of large fibers. We performed a series of collision studies by stimulating the ulnar nerve submaximally at proximal and distal sites at varying levels of stimulation intensity from motor threshold to supramaximal stimulation. The results suggest that variation in intraneural topography at different sites allows different large diameter nerve fiber subpopulations to be activated at submaximal stimuli, and emphasizes the importance of supramaximal stimulation to determine a valid conduction velocity. © 1994 John Wiley & Sons, Inc.
Deflazacort in Duchenne dystrophy: Study of long‐term effect
Authors: Angelini C. , Pegoraro E. , Turella E. , Intino M. T. , Pini A. , Costa C.
Published: January 2005

A randomized double‐blind controlled trial of deflazacort was conducted in 28 Duchenne muscular dystrophy patients either treated with deflazacort 2.0 mg/kg alternate‐day therapy or placebo. The deflazacort group showed significant improvement in climbing stairs (P < 0.01), in rising from a chair, Gower's maneuver, and walking (P < 0.0025) after 6 months of treatment. After 1 year, all the above changes remained significantly improved and the MRC index was significantly better (P < 0.05) in the treated croup. After 2 years, a significant change was found in the MRC index: higher scores in walking, chair rising (P < 0.02), and grade and time of Gower's maneuver (P < 0.05) were found. The mean time for loss of ambulation for the treated group after we started the trial was 20.5 ± 11 months; for the placebo group it was 33.2 ± 9 months (placebo vs. deflazacort group, P < 0.05). Our treated patients lost their ambulation at a median age of 11.8 years vs. 10.5 years in the placebo group. Side effects were mild, consisting of moderate weight gain and slight behavioral changes. © 1994 John Wiley & Sons, Inc.