摘要:

AbstractSuspected ulnar neuropathy at the elbow is commonly evaluated in the electromyography lab. In this report the anatomy and pathology of ulnar elbow lesions are reviewed. The patterns of electrophysiologic abnormality that have been reported in the literature and in the author's own laboratory are discussed along with a suggested routine for evaluation.

ISSN:0148-639X    

DOI:10.1002/mus.880111002

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1988

数据来源: WILEY

摘要:

AbstractIsomyosin analyses by biochemical, immunochemical, and histochemical investigations have been carried out in five sheep following unilateral recurrent laryngeal nerve paralysis and direct functional electrostimulation of the denervated cricoarytenoid posterior muscle. Myosin light chains were identified by two‐dimensional gel electrophoresis. Myosin heavy chains were analyzed by one‐dimensional SDS‐polyacrylamide gel electrophoresis. Slow myosin heavy chain was identified by orthogonal peptide mapping and immunochemistry. The stimulation effect at cellular level was determined using adenosine triphosphatase (ATPase) histochemistry. A dramatic increase of the type 1 fiber area (slow, fatigue‐resistant fibers) could be seen after many weeks of an increasing regime of low‐frequency direct electrical stimulation. Biochemically, the amout of slow myosin was always higher than in normal muscles. Some muscles were transformed almost completely to the slow type. At the time they were studied and with the methods employed, the expression of embryonic isomyosin was not observed. In conclusion, after numerous weeks of maintained functional activity, elicited by direct electrostimulation, the denervated muscle regionally showed areas of hypertrophy or at least lack of atrophy of slow myofibers without major signs of musc

ISSN:0148-639X    

DOI:10.1002/mus.880111003

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1988

数据来源: WILEY

摘要:

AbstractSegments of mammalian, including human, skeletal muscle 1–2 cm long can be induced to shed vesicles by treatment with collagenase in a high‐KCl solution containing no added calcium. The vesciles are encompassed by clean sarcolemma so that the gigaseal necessary for patch‐clamping is readily formed. The properties of inwardly rectifying potassium channels and of calcium‐activated potassium channels in patches detached form such vesicles are shown to be consistent with expectations based on earlier studies on intact muscle fibers and with patch clamp results on the same type of channels in other tissues. A cholride channel which rectifies outwardly with a conductance ranging from 15 to 50 pS is also described. The utility of sarcolemmal vesicles for the study of ion channels in human biopsy material is di

ISSN:0148-639X    

DOI:10.1002/mus.880111004

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1988

数据来源: WILEY

摘要:

AbstractThree patients with Guillain‐Barré syndrome underwent electrophysiological examination prior to and during a period of rapid clinical recovery. In each case, improved strength of the abductor digiti minimi coincided with electrophysiologic evidence of a marked reversal of proximal conduction block. In contrast, the degree of distal conduction block remained relatively unchanged after stimulation at the wrist, elbow, axilla, and Erb's point. These findings indicate that rapid motor recovery, early in the course of Guillain‐Barré syndrome, can result from reversal of proximal conduction block and explains the often noted dissociation between clinical improvement and conventional distal nerve conduction st

ISSN:0148-639X    

DOI:10.1002/mus.880111005

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1988

数据来源: WILEY

摘要:

AbstractFollowing neonatal nerve injury fast skeletal muscles recover less well than slow ones. This is because many muscle fibers are lost during reinnervation. Since fast muscles normally contain a small population of slow muscle fibers, we have used a monoclonal antibody to slow myosin heavy chains (SMHC) to study their number and pattern of distribution in fast muscles following temporary denervation at 5–6 days of age and subsequent reinnervation. During this time the original distribution of slow fibers changed to one showing irregular grouping, indicating that reinnervation of muscles after neonatal nerve injury is as nonselective as it is after nerve injury in adults. Despite a large reduction in the total number of muscle fibers during reinnervation, the number of slow fibers did not decrease. Thus muscle fiber loss was at the expense of the fast motor units alon

ISSN:0148-639X    

DOI:10.1002/mus.880111006

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1988

数据来源: WILEY

摘要:

AbstractWe compared the configurational and firing properties of 7270 motor unit action potentials (MUAPs) recorded with either concentric (CNE) or monopolar (MNE) needle electrodes from the brachial biceps and anterior tibial muscles of 10 healthy young adults (mean age 27 ± 4.5 years) using automatic decomposition electromyography (ADEMG). In both muscles, mean MUAP amplitude, rise rate, and number of turns were significantly greater when recorded with MNE (pairedt‐test,P0.05 in each case). These findings indicate that it is acceptable to generalize normative data on MUAP duration and firing rate from one electrode type to another, but that measures of MUAP amplitude and complexity require independent normative databas

ISSN:0148-639X    

DOI:10.1002/mus.880111007

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1988

数据来源: WILEY

摘要:

AbstractClinicopathologic findings from two golden retriever dogs with an inherited, progressive, degenerative muscle disease that were studied until 27 and 40 months of age are described. Initial clinical signs included stilted gait and simultaneous advancement of their pelvic limbs. Further gait restriction and muscle hypertrophy eventually occurred. Serum creatine kinase was dramatically elevated (>10,000 U/L). There were persistent “spontaneous” high‐frequency discharges (pseudomyotonia) on electromyographic evaluation. Features of both muscle fiber degeneration (hyaline fibers, myophagocytosis) and regeneration (small basophilic fibers) were seen on light microscopy. Similar ultrastructural changes (fiber hypercontraction, increased myoblasts) were present. On morphometric histochemical evaluation, mean fiber diameter of both type 1 and 2 fibers was increased compared with controls in two of three muscles examined. There was no apparent fiber type predominance. Scattered ragged red fibers were seen, but this appeared to be a nonspecific finding of either muscle fiber regeneration or degeneration. These findings and potential contributing pathophysiologic mechanisms are discussed in relation to Duchenne muscular dyst

ISSN:0148-639X    

DOI:10.1002/mus.880111008

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1988

数据来源: WILEY

摘要:

AbstractA 31‐year‐old male developed paresthesia and numbness of mainly the right foot following exposure to nonfreezing temperatures under moist conditions over a period of 1 week. The symptoms gradually improved over several months. When seen for electrophysiological studies 6 months after the injury, there was no sensory loss on clinical examination, although he continued to complain of distal numbness of the right foot. The right extensor digitorum brevis muscle was atrophic, and the distal motor latency in the peroneal nerve was prolonged. Conduction studies of the right sural nerve showed a predominantly distal diminution of the SAP evoked by electrical stimulation at the dorsum pedis. Action potentials evoked by tactile stimulation of Pacinian corpuscles showed a prolonged latency on the symptomatic side, suggesting that the most pronounced pathological changes in immersion injury may be localized to the very distal portion of the nerve at the nerve fiber‐receptor jun

ISSN:0148-639X    

DOI:10.1002/mus.880111009

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1988

数据来源: WILEY

摘要:

AbstractTo correlate the accuracy of electromyography in diagnosing the correct root involved in cervical radiculopathy, 20 patients with cervical radiculopathy, diagnosed by electromyography using strict inclusion and exclusion criteria, were studied. Metrizamide myelography/computerized tomography were evaluated in all 20 patients independently, and the involved root was defined. The root involved, using the EMG examination and the myotome chart of the Medical Research Council, was C5 in 3 patients, C6 in 6, C7 in 9 patients, and C8 in 2 patients. The overall correlation with myelography/CT was 65% (33.3, 66.6, 77.7, and 50% for C5, C6, C7, and C8, respectively). EMG done properly has a good correlation of myelography/CT. This correlation is higher (73.3%) for the commonly occurring cervical radiculopathies (C6 and C7).

ISSN:0148-639X    

DOI:10.1002/mus.880111010

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1988

数据来源: WILEY

摘要:

AbstractThe magnetic stimulator was compared with percutaneous electrical stimulation for activation of the median nerve at the wrist in four volunteers. Magnetic stimulation was unable to achieve supramaximal stimulation without activation of the ulnar nerve. The point of nerve depolarization could not be reliably estimated from the relationship of the stimulator head to the nerve. We conclude that the magnetic stimulator coil is as yet not suitable for routine electrodiagnositic use in the peripheral nervous system.

ISSN:0148-639X    

DOI:10.1002/mus.880111011

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1988

数据来源: WILEY