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Electrodiagnostic medicine is a specific area of physical medicine and rehabilitation in which a physiatrist uses clinical history, physical examination, and the techniques of electrophysiologic study to diagnose and treat neuromuscular disorders. The roles of electrodiagnosis include (1) determining the localization and distribution of a lesion and severity of a disease, (2) characterizing the evolution of a disease, (3) estimating prognosis, (4) differentiating neuropathy and myopathy, and (5) monitoring the response to a treatment. For these to be achieved, a logical approach during every step of testing is needed, followed by data interpretation and clinical correlations.

To investigate the immediate effects of bilateral upper-extremity sanding exercises on conduction and morphologic characteristics of the median and ulnar nerves at the wrist in hemiparetic subjects and control subjects.Case control study using a pretest-post-test design.Inpatient rehabilitation department affiliated with a teaching hospital.Thirty hemiparetic subjects and 21 matched control subjects who met our inclusion criteria and had no history of diseases that may have predisposed them to peripheral neuropathies were recruited for this study.Bilateral nerve conduction tests and ultrasonographic evaluations were performed on each subject before and immediately after a 30-minute bilateral sanding exercise with a frequency of 5 repetitions per minute.The effects of exercises on bilateral median and ulnar wrist nerves were assessed with the use of sensory and motor nerve conduction velocity tests and by width/thickness ratios in ultrasonographic evaluations.In the hemiparesis group, the pre-exercise amplitude of the motor component for the median and ulnar nerves were respectively lower than the corresponding values in the control group (P.05), whereas the pre-exercise amplitude and velocity of the sensory component were lower than the corresponding values in the control group (P.01). After the exercise, the assessments for the affected side showed reductions in the conduction velocity of the sensory component and an increase in the width/thickness ratio for the median nerve (P.05).The median and ulnar nerves at the wrist in hemiparetic subjects before sanding exercises showed different conduction characteristics compared with control subjects. Their affected side also demonstrated significant conduction and morphologic changes after the exercises. These subclinical findings may be attributed to different mechanisms such as overuse, spasticity, and demyelinating changes. Prevention of these subclinical changes is recommended to enhance exercise safety in hemiparetic patients.

Chang C-W, Chang K-Y, Chen Y-R, Kuo P-L. Electrophysiologic evidence of spinal accessory neuropathy in patients with cervical myofascial pain syndrome. Objective To evaluate whether or not spinal accessory neuropathy exists in patients with cervical myofascial pain syndrome (MFPS). Design Prospective study. Setting A neurophysiologic laboratory in a university hospital. Participants Patients with cervical MFPS (n=25) and healthy controls (n=20). Interventions Not applicable. Main Outcome Measures We performed nerve conduction studies (NCSs) in bilateral spinal accessory nerves, and electromyography and stimulated single-fiber electromyography in the trapezius muscles of all patients and controls. Parameters including nerve conduction velocities (NCVs), amplitudes and areas of compound muscle action potentials (CMAPs), and mean consecutive differences (MCDs) in single-fiber electromyography were measured, analyzed, and compared with the disease durations of the patients. Results Spinal accessory NCSs showed normative NCVs but with prominently reduced CMAP amplitude in the patients with cervical MFPS, which is recognized as an axonal neuropathy of the spinal accessory nerves. Electromyography showed prominent evidence of denervation and reinnervation patterns in 48% of the MFPS patients. The abnormal MCDs in single-fiber electromyography indicated a synaptic delay of motor endplates in the motor units, and may signify evolving instability of neuromuscular transmission in the spinal accessory nerves innervating trapezius muscles of the patients. Conclusions This study demonstrates electrophysiologic evidence of neuroaxonal degeneration and neuromuscular transmission disorder in a significant proportion of patients with cervical MFPS. We suggest that spinal accessory neuropathy may be associated with cervical MFPS.

Measurement of anterior/posterior shoulder tightness, humeral external/internal rotation range of motion (ROM), scapular upward rotation/tipping ROM, and functional limitations were made in 46 patients with unilateral stiff shoulders (SSs) using a clinical measurement (shoulder tightness), a three-dimensional electromagnetic tracking device (shoulder ROM), and self-reports of function. Patients with SSs in their dominant shoulder demonstrated statistically greater posterior shoulder tightness compared to nondominant shoulder. Control dominant shoulders demonstrated decreased internal ROM as compared with control nondominant shoulders (p=0.021). In SSs, significant relationships were found between humeral internal rotation ROM and posterior shoulder tightness (R=0.49, p

This study was done to evaluate the effect of rising temperature on nerve conduction parameters in 22 patients with carpal tunnel syndrome (CTS). We wanted to find out whether diseased nerves responded to temperature rise in a different manner from normal controls. For this purpose a group of 20 healthy individuals were also tested. With rising temperature motor nerve conduction velocities increased, whereas latencies, amplitudes and duration of the compound muscle action potential decreased in both groups. These changes were not statistically significant between the two groups. Sensory nerve conduction parameters yielded basically similar findings except for a significantly smaller reduction in amplitude of the compound nerve action potential (CNAP) in the CTS group (p < 0.005). We conclude that there is a different response in the sensory CNAP amplitude between normal and CTS groups, but the same nerve conduction correction formulae for temperature can be used in CTS patients as in normal individuals in the event of low skin temperature.

The study of central nervous pathway conductions established clinical values both in afferent and efferent systems in recent decades. Somatosensory evoked potential was originally an estimated dysfunction of afferent sensory pathways in the spinal cord. However, it is limited in the evaluation of cord function in dorsal column. Motor evoked potential (MEP) study, developed by Merton and Morton 11) since 1980, has become a useful tool in evaluation of electrophysiologic function of motor pathways in central nervous diseases including spinal cord disorders. For measurement of spinal cord motor conduction velocity (SCMCV), invasive methods with direct spinal cord stimulations and recordings during spinal surgery have been introduced, however, they were not commonly applied in clinical practice. MEP study by pulse magnetic stimulation developed by Barker and coworkers 1) since 1985, moreover, offering advantages of non-invasive, painless and deep penetration of nerve tissues has the potentials in evaluating spinal cord dysfunction, brain diseases 12) and deep seated nerve pathology.

OBJECTIVE. We investigated how verbal instructions and target location interacted to influence reaching movement of the less-affected limb in participants with and without unilateral cerebrovascular accidents (CVAs). METHOD. Using a counterbalanced repeated-measures design, 26 people with CVA and 24 age-matched healthy people performed the reaching tasks under 4 conditions formed by the crossing of verbal instructions (speed and accuracy emphasis) and target locations (ipsilateral and contralateral to the performing hand). RESULTS. In the control groups, speeded instructions and ipsilateral reaches elicited significantly more preprogrammed movements than did accuracy instruction and contralateral reaches, respectively. Similar patterns of performance in response to task constraints were found in the CVA groups except for movement initiation in the right CVA group. CONCLUSION. Instruction and locations interacted to constrain reaching movements in both control and CVA groups. The combination of speeded instruction and ipsilateral reach may optimize movement performance of the less-affected limb in stroke patients.

Background and PurposeThe purpose of this study was to compare the use of 3 mobilization techniques—end-range mobilization (ERM), mid-range mobilization (MRM), and mobilization with movement (MWM)—in the management of subjects with frozen shoulder syndrome (FSS).SubjectsTwenty-eight subjects with FSS were recruited.MethodsA multiple-treatment trial on 2 groups (A-B-A-C and A-C-A-B, where A=MRM, B=ERM, and C=MWM) was carried out. The duration of each treatment was 3 weeks, for a total of 12 weeks. Outcome measures included the functional score and shoulder kinematics.ResultsOverall, subjects in both groups improved over the 12 weeks. Statistically significant improvements were found in ERM and MWM. Additionally, MWM corrected scapulohumeral rhythm significantly better than ERM did.Discussion and ConclusionIn subjects with FSS, ERM and MWM were more effective than MRM in increasing mobility and functional ability. Movement strategies in terms of scapulohumeral rhythm improved after 3 weeks of MWM.

Objective To demonstrate a method of sensory nerve conduction study (NCS) for the medial calcaneal nerve (MCN) and confirm the medial calcaneal neuropathy in patients with plantar fasciitis (PF). Methods Twenty-six patients with clinical and ultrasonographic diagnosis of PF participated in the present study. An antidromic method for sensory NCS of MCN was performed in each patient and in 30 controls. The conduction latency, sensory nerve conduction velocity (SNCV) and amplitude of the sensory nerve action potential (SNAP) were measured and the correlation of the SNCV of MCN with both body weight and body mass index (BMI) was studied. Results The mean conduction latency obtained in the MCN was greater in the PF patients than in the normal controls. Mean SNCV and SNAP amplitude of the MCN were significantly less in the PF patients than in the normal controls. Body weight and BMI were greater in PF patients than in controls. Six patients were identified as having a medial calcaneal neuropathy by using the criteria of the lowest normal values of the NCS of MCN from the normal controls. Conclusions Medial calcaneal neuropathy is associated with PF. The present method of sensory NCS is useful and objective in the diagnosis of the medial calcaneal neuropathy. Significance Medial calcaneal neuropathy was confirmed by the sensory NCS of MCN and shown to be associated with PF.

The phenol nerve block has been widely used in clinical practice for spasticity reduction, but the correlation between the dosage of phenol and its effectiveness has seldom been discussed. The objective was to determine the optimal duration of phenol in contact with the nervous tissue and to investigate the dose-response relationship of 5% aqueous phenol solution by percutaneous nerve block in rats. Group I (n = 8) received sciatic nerve block by bathing the nerves in phenol solution, and group II (n = 40) by injecting phenol percutaneously. Group IIa to IId received different volumes (0.80, 0.16, 0.08 and 0.04 ml) and group IIe received normal saline. Compound muscle action potential (CMAP) was measured pre-injection and at 90 and 270 sec after injection and after surgical exposure of the nerves. The duration of CMAP reduced by 10%, 25%, 50%, 75% and 100% after phenol injection was also recorded. The mean latency for the evoked response to subside in direct phenol application (group I) and percutaneous nerve block (group IIa) were 73.5 ± 5.9 and 62.4 ± 7.6 sec, respectively. There was no statistical difference for the time periods in the blocking effect elicited by phenol solution between these two methods. Ninety sec was set as the optimal duration for phenol to produce complete conduction blockage. Higher volume of phenol produced more significant blocking effect at 90 and 270 sec after injection. Percutaneous injection with 0.16 ml of phenol solution had the same blocking effect as 0.8 ml. The continuous injection model for percutaneous phenol block indeed used significantly more phenol than actually needed. Clinically, the progressive injection model can be used to minimize injection volume.

Estimating the focal size and position of a high-intensity focused ultrasound (HIFU) transducer remains a challenge since traditional methods, such as hydrophone scanning or schlieren imaging, cannot tolerate high pressures, are directional, or provide low resolution. The difficulties increase when dealing with the complex beam pattern of a multielement HIFU transducer array, e.g., two transducers facing each other. In the present study we show a novel approach to the visualization of the HIFU focus by using shockwave-generated bubbles and a diagnostic B-mode scanner. Bubbles were generated and pushed by shock waves toward the HIFU beam, and were trapped in its pressure valleys. These trapped bubbles moved along the pressure valleys and thereby delineated the shape and size of the HIFU beam. The main and sidelobes of 1.1- and 3.5 MHz HIFU beams were clearly visible, and could be measured with a millimeter resolution. The combined foci could also be visualized by observing the generation of sustained inertial cavitation and enhanced scattering. The results of this study further demonstrate the possibility of reducing the inertial cavitation threshold by the local introduction of shock wave-generated bubbles, which might be useful when bubble generation and cavitation-related bioeffects are intended within a small region in vivo.

Understanding the control of movement requires an awareness of how tasks constrain movements. The present study investigated the effects of two types of task constraints—spatial accuracy (effector size) and target location—on reaching kinematics. 15 right-handed healthy young adults (7 men, 8 women) whose mean age was 23.6 yr. ( SD = 3.9 yr.) performed the ringing task under six conditions, formed by the crossing of effector size (larger vs smaller size) and target location (left, right, or a central position). Significant main effects of effector size and target location were found for peak velocity and movement time. There was a significant interaction for the percentage of time to peak velocity. The findings suggested that task constraints may modulate movement performance in specific ways. Effects of effector size might be a consequence of feedforward and feedback control, and location effects might be influenced by both biomechanical and neurological factors.

Study design: A study of the clinical features, physical activity, muscle enzyme, electromyography and histopathological alternations of muscles in patients with post-polio syndrome (PPS). Objective: To assess the varied patterns of PPS in Taiwan. Setting: Taiwan. Methods: Thirty-one patients who fulfill the inclusion criteria of PPS were selected for study. Clinical features, physical activity scale, serum concentrations of creatine kinase, electromyography and histopathological alterations of muscles were assessed and correlated to the causes of PPS patients. Results: Patients with PPS in Taiwan are relatively young, with a mean age of 39.3 years. Elevated concentration of creatine kinase was found predominantly in male patients with higher physical activities. Electromyographic examinations as well as histological tests of affected muscles revealed prominent evidence of chronic and active denervation with reinnervation in PPS patients. Conclusion: Patients with PPS in Taiwan are young. Thus, PPS should not be attributed to aging. Physical attrition with degradation of nerve terminals is considered the main cause of this disease. Sponsorship: This study was supported by the National Science Council, Republic of China under grant no. NSC-83-0412-B002-302. Spinal Cord (2001) 39, 526–531.

Objectives : To evaluate the primitive reflexes by electrophysiological assessments and their correlation with the cognitive and physical functioning of stroke patients. Methods : Electrophysiological studies of primitive reflexes including jaw jerk, snout reflex, glabellar reflex, and corneomandibular reflexes were performed in 38 stroke patients and 26 normal controls. Cognitive function of patients was assessed by Modified Mini-Mental State (3MS) Examination and logical memory test. The Chinese Functional Independence Scale (CFIS) was used to evaluate the physical functioning and social domains of stroke patients. Results : The presence rate of primitive reflexes was higher in stroke patients than in normal controls. Wave amplitude of snout and corneomandibular reflexes obtained from stroke patients was greater than those from controls. No definite difference in reflex conduction latencies was observed between the two groups. A regression relationship was noted between the wave amplitude of snout reflexes and the 3MS and CFIS scores of stroke patients. Conclusion : Primitive reflexes can be measured by electrophysiological assessments. The results may serve as an objective and useful parameter in evaluation of cognition and physical functioning of stroke patients.

We report a 47-year-old male stroke patient with nasopharyngeal cancer (NPC) and protein C deficiency. The patient was diagnosed with NPC and received a complete course of radiotherapy. Infarction stroke occurred 28 months after radiotherapy and magnetic resonance imaging of the brain confirmed the diagnosis. Carotid duplex sonography showed 50–79% stenosis in his left internal carotid artery. Coagulation profiles indicated protein C deficiency. After medical treatment and rehabilitation, the patient regained the ability to walk and he could perform most of his daily activities. Radiotherapy-induced carotid stenosis is an exacerbating feature of stroke in patients with protein C deficiency. We suggest early carotid duplex sonography and survey of the coagulation profile to prevent a stroke in patients with NPC.

Objective: To study the immediate effects of maximal voluntary (MV) breathing, with and without abdominal weight (AW) or inspiratory resistance (IR), on inspiratory muscle functions in chronic tetraplegic patients. Design: A crossover trial design. Setting: Rehabilitation department of a university hospital. Participants: Nine tetraplegic men injured at the C4 to T1 levels, with a mean duration of injury of 72.8 months. Interventions: Each subject performed MV breathing without and with AW load (AWMV breathing) and IR load (IRMV breathing) separately. Main Outcome Measures: Electromyographic (EMG) activity of the inspiratory muscles, mouth pressure, inspiratory flow, and inspiratory volume. Results: AWMV breathing evoked greater diaphragmatic EMG activity, inspiratory flow, and inspiratory volume than did IRMV breathing, although the increase of diaphragmatic EMG activity was not statistically significant. Conversely, IRMV breathing produced greater sternocleidomastoid EMG activity and negative mouth pressure than did AWMV breathing. Both AWMV and IRMV breathing evoked greater inspiratory muscle EMG activity than did MV breathing. Conclusion: AW and IR loads have differential immediate effects on the inspiratory muscle functions during MV breathing in patients with chronic tetraplegia, suggesting that these two breathing maneuvers may have dissimilar mechanisms of training in such patients. The muscle EMG activity evoked during MV breathing with AW or IR is greater than that without a mechanical load, implying that mechanically loaded training in tetraplegic patients results in load compensatory adjustments via their respiratory motor output to improve respiratory function.

Neuronal degradation accompanied by axonal degeneration has been known to occur in lower motor neurons following a stroke. In the present study, the functional integrity of neuromuscular transmission was assessed, utilizing a sensitive electrodiagnostic method consisting of stimulated single-fiber electromyography (SFEMG), along with axonal microstimulation, in paralytic muscles of stroke patients. Neuromuscular jitter was measured in the hemiplegic side extensor digitorum communis (EDC) as well as in anterior tibial (AT) muscles for 28 stroke patients and also for 13 age-matched controls. The disease duration, i.e. from the onset of stroke until the stimulated SFEMG examination, extended from 2 months to 8 years. Mean jitters obtained in EDC and AT muscles of stroke patients were found to be significantly greater than those in normal controls. Mean jitters obtained in severely weak muscles of stroke patients were greater than those in moderately weak muscles. Positive correlations were noted between the increased jitter and the disease duration from the onset of stroke until the time of the stimulated SFEMG test. These findings demonstrate a dysfunction of neuromuscular transmission in the paralytic muscles of stroke patients and suggests that trans-synaptic degeneration of motor neurons may occur in stroke. Furthermore, the neuronal degradation in stroke was positively correlated with the course duration of the disease.

Retrospective case study.Report a rare case of cervical myelopathy induced by calcium pyrophosphate dehydrate (CPPD) deposition in multiple cervical levels.An area teaching hospital in Taiwan.A patient with cervical myelopathy was evaluated by computerized tomography (CT) scan and magnetic resonance (MR) image. CPPD deposition known as pseudogout was diagnosed and approved by a polarized microscope.A prominent hypertrophy of ligmentum flavum and a retro-odontoid bulging mass induced cord compression were found in CT scan and MR image. CPPD deposition was confirmed by the histological examinations in the ligamentum flavum at the spinal levels of C3-C6. After decompression surgery of spine and comprehensive rehabilitation, the patient's neurological symptoms subsided and her neurological functions improved leading to a good prognosis.CPPD deposition in cervical spine occurring at multiple levels is rare. Image studies with CT scan and MR are complementary in the diagnosis of CPPD-induced myelopathy. Surgical decompression is always required and expected to have a good outcome.

Study Design A prospective motor-evoked potential study with measurement of spinal cord motor conduction velocity in the thoracolumbar cord was performed before and after decompression surgery in 30 patients with cervical spondylotic myelopathy. Objectives To evaluate the neurofunctional integrity of the spinal motor pathways in cervical spondylotic myelopathy in patients compared with age-matched control subjects; to assess any changes after posterior surgical decompression; and to correlate such changes with functional outcomes so that the predictability of preoperative motor-evoked potentials could be determined. Summary of Background Data Previous studies evaluating neurologic function and predictability of surgical results in cervical spondylotic myelopathy patients always depended on the morphologic changes of the cord and spinal structures. The recently developed motor-evoked potential study and noninvasive measurement of spinal cord motor conduction velocity may provide an objective method to evaluate physiologic motor function in cervical spondylotic myelopathy patients. Methods Spinal cord motor conduction velocity in the thoracolumbar cord was measured using percutaneous magnetic stimulation over the motor cortices and F-wave studies in median and peroneal nerves. Motor function of cervical spondylotic myelopathy patients was graded according to evaluation of signs of cord involvement, ambulation, and degree of dependence in activities of daily living. Evaluation was performed at 6 months, 1 year, and 2 years after decompression surgery. Results Motor functional improvement accompanied by increased spinal cord motor conduction velocity occurred in Grade I patients with a mild neurologic dysfunction but not in Grade II or III patients with a moderate-to-severe neurologic deficit. Neurologic improvement does not appear to occur until 6 months after surgery. Conclusions Measurement of spinal cord motor conduction velocity may provide an objective and quantitative approach to assessing the motor functional integrity of the spinal cord and serving as a predictor in evaluating surgical outcome in patients with cervical spondylotic myelopathy.

Objective To investigate the relative and absolute reliabilities of the myotonometer. Design Psychometric study. Setting Three medical centers. Participants Patients with stroke (N=61). Interventions Not applicable. Main Outcome Measures Muscle tone, elasticity, and stiffness of relaxed affected deltoid, triceps brachii, biceps brachii, extensor digitorum, flexor carpi radialis, and flexor carpi ulnaris were measured twice, 30 minutes apart, using the myotonometer. Intraclass correlation coefficient, a relative reliability index, was calculated for 3 muscular properties and for each muscle to examine the degree of consistency and agreement between the 2 test sessions. Absolute reliability indices, including the SEM, smallest real difference, and Bland-Altman limits of agreement, were used to quantify measurement errors and check systematic biases of the 2 test sessions. Results The intraclass correlation coefficients were .83 to .95 for muscle tone, elasticity, and stiffness of all muscle groups. The SEM and the smallest real difference of muscle tone, elasticity, and stiffness of the biceps were the smallest among the 6 muscles tested. The Bland-Altman analyses showed no systematic bias between most of the repeated measurements. Compared with other muscles, biceps had narrower limits-of-agreement ranges, indicating that the myotonometric measurements of the biceps had higher stability and less variation over time. Conclusions The myotonometer reliably measures muscular properties, with good relative and absolute reliabilities. These findings are useful for clinicians and researchers to assess muscle properties reliably and determine whether a real change has occurred in groups and on individual levels of patients with stroke.

Treatment strategies targeting abnormal shoulder kinematics may prevent pathology or if the pathology develops, shorten its duration. We examined the effectiveness of the end-range mobilization/scapular mobilization treatment approach (EMSMTA) in a subgroup of subjects with frozen shoulder syndrome (FSS). Based on the kinematics criteria from a prediction method, 34 subjects with FSS were recruited. Eleven subjects were assigned to the control group, and 23 subjects who met the criteria were randomly assigned to the criteria-control group with a standardized physical therapy program or to the EMSMTA group. Subjects attended treatment sessions twice a week for 8 weeks. Range of motion (ROM), disability score, and shoulder complex kinematics were obtained at the beginning, 4 weeks, and 8 weeks. Subjects in the EMSMTA group experienced greater improvement in outcomes compared with the criteria-control group at 4 weeks (mean difference=0.2 of normalized hand-behind-back reach) and 8 weeks (mean difference=22.4 degrees humeral external rotation, 0.31 of normalized hand-behind-back reach, 7.5 disability, 5 degrees tipping and 0.32 rhythm ratio). Similar improvements were found between the EMSMTA group and control group. The EMSMTA was more effective than a standardized physical therapy program in a subgroup of subjects who fit the criteria from a prediction method.

The Tromner sign is commonly used as a clinical neurological examination for upper motor neuron lesions above the fifth or sixth cervical segments of the spinal cord. This study aims to assess and quantify the Tromner signs utilizing electrophysiological test, and correlate to the severity of cord compression in cervical spondylotic myelopathy (CSM). We enlisted 46 CSM patients, and 30 healthy persons as controls. Manual Tromner and Hoffmann signs were tested in all subjects. By using a self-designed instrument, we performed electrophysiological assessments for the Tromner signs in patients and controls. Parameters of conduction latencies and amplitude of muscle action potentials were measured and compared with the cord compression ratios in CSM patients. The results showed a greater diagnostic sensitivity for the quantified Tromner signs in comparison to those of manual Tromner signs and Hoffmann signs. We found a positive correlation between the amplitude of muscle action potentials obtained in the Tromner signs and the cord compression ratios in the patients with CSM. In conclusion, the Tromner signs can be measured by electrophysiological assessments. We demonstrate a new quantification method for an established neurological sign. Not only is Tromner sign a highly sensitive test in clinical neurological examination, the electrophysiological assessment of this sign can also serve as an objective marker for evaluation of the severity of cervical cord compression.

The literature suggests a possible relationship between carrying angle and nontrauma-related ulnar neuropathy. To confirm that relationship, we asked whether carrying angle is a risk factor in patients with nontrauma-related ulnar neuropathy. We measured the carrying angles of the elbow in 36 patients with a clinically and electrophysiologically confirmed diagnosis of nontraumatic ulnar neuropathy at the elbow and in 50 healthy control subjects. Correlation analysis was performed between carrying angles and parameters of nerve conduction studies, including nerve conduction velocities and amplitudes of muscle and nerve action potentials. The mean carrying angle was greater in the patients than in the control subjects. Females had a greater carrying angle than males. We observed an inverse relationship between carrying angles and motor nerve conduction velocities at cross-elbow segments of the ulnar nerves and with sensory nerve conduction velocities of the distal ulnar nerves. An increased carrying angle of the elbow appears to be an independent risk factor of nontrauma-related ulnar neuropathy. Level of Evidence: Level III, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

An analysis of secondary shoulder motions (humeral rotation, humeral head anterior/posterior translation, scapular tipping, and scapular upward/downward rotation) in subjects with anterior/posterior shoulder tightness provides the opportunity to examine the role of tightness as a means of affecting shoulder motions. Subjects with shoulder tightness (anterior, n =12; posterior, n =12) elevated their arms in the scapular plane. Three replicated movements were performed to the maximum motions. Kinematics data were collected by FASTRAK 3D electromagnetic system. To determine if a significant difference of the secondary motions existed between anterior/posterior shoulder tightness, two-factor mixed ANOVA models with the repeated factor of elevation angle (five elevation angles) and the independent factor of group were calculated. The relationships between the self-reported functional scores (Flexilevel Scale of Shoulder Function, FLEX-SF) and abnormal shoulder kinematics were assessed. For humeral head anterior/posterior translation, the subjects with posterior tightness demonstrated anterior humeral head translation (10mm, p =0.019) compared to subjects with anterior tightness. The subjects with anterior tightness demonstrated less posterior tipping (2.2°, p =0.045) compared to subjects with posterior tightness. The humeral anterior translation had moderate relationships with FLEX-SF scores ( r =−0.535) in subjects with posterior tightness. The scapular tipping had moderate relationships with FLEX-SF scores ( r =0.432) in subjects with anterior tightness. In conclusion, the secondary motions were different between subjects with anterior and posterior shoulder tightness. During arm elevation, less scapular posterior tipping and less posterior humeral head translation in subjects with anterior and posterior shoulder tightness, respectively, are significantly related to self-reported functional disability in these subjects.

Objective: To evaluate the change in motor evoked potential parameters following transcranial magnetic stimulation in patients with chronic complete thoracic cord injury. Design: A cross-sectional study. Subjects: Eighteen patients with chronic complete thoracic cord injury and 18 age- and sex-matched healthy controls were included in the study. The mean post-injury duration was 13.0 (standard deviation (SD) 6.0) years. Methods: The latency, amplitude, central conduction time and peripheral conduction time of motor evoked potentials from bilateral abductor pollicis brevis and first dorsal in terosseous muscles following transcranial magnetic stimulation were measured and compared between the patients and healthy controls. The predicting variables for central conduction time, including age, sex, height, illness duration and job activity, were analysed using a simple correlation and stepwise multiple regression model. Results: The patients with complete thoracic cord injury had longer central conduction time recording of the dominant hand in both abductor pollicis brevis and first dorsal interosseous muscles. The difference in latency approached significance between the patients and controls. There was no statistical difference in amplitude between them. Regression analysis demonstrated that patients who were older, less physically active and with longer illness duration showed prolonged central conduction time. Conclusion: The central conduction time in the dominant hand of chronic complete thoracic cord injury is prolonged. This study revealed motor reorganization of the central nervous system in complete thoracic cord injury. Decreased physical activity and prolonged illness may cause these changes.

Direct spinal nerve stimulation was compared with needle electromyography (EMG) in 40 patients who were suspected of having an L5 or S1 radiculopathy. For spinal nerve stimulation, we adapted a monopolar needle electrode inserted deep into the paraspinal muscle. The minimal latency, amplitude, and negative phase area of compound muscle action potential from myotomal muscles were recorded with computer assistance. Abnormality was considered to be significant when the value fell outside of 2 SD of control mean values. Among 17 patients with clinical evidence of radiculopathy, needle EMG was abnormal in 10 patients (58.8%), whereas in the nerve stimulation test the abnormalities were shown in 16 patients (94.1%); in amplitude difference and the abnormal area, differences were shown in 12 patients (70.6%). Among 23 patients with only subjective symptoms of radiculopathy, needle EMG was abnormal in nine patients (39.1%), whereas the abnormal amplitude differences were shown in 18 patients (78.3%) and 15 patients (65.2%) with abnormal area difference by spinal nerve stimulation, respectively. Direct spinal nerve stimulation is recognized as an objective and sensitive test in the diagnosis of lumbosacral radiculopathy.

The mechanism of myofascial pain syndrome (MPS) is unclear. Previous reports pointed out that pathogenesis of either referred pain or local twitch response in trigger point of MPS is related to the nerve degeneration and disintegration of motor and sensory nerves in spinal cord. The purpose of the present study is to investigate the evidence of neuromuscular transmission disorders in trigger point muscles of patients with MPS by using stimulated single-fiber electromyography (SFEMG) examination. Twenty-three patients with neck MPS and 16 age-matched controls attended for the present study. The jitter or mean consecutive difference (MCD) was calculated as the mean of the absolute differences for 30 consecutive interpotential intervals between stimuli and single-fiber potentials in trapezius and levator scapulae muscles. The relationship between the MCD values and the disease duration was measured. The results showed significantly increased MCDs in trapezius and levator scapulae muscles in MPS patients. MCD values measured in the trigger point muscles were found to be positively correlated with the disease duration. The present study with axonal microstimulation and SFEMG demonstrates a prominent evidence of neuroaxonal degeneration and neuromuscular transmission disorders in the trigger point muscles of MPS patients. The mechanism of MPS is possibly implicated with the degeneration of motor neurons.

Physical therapy is an intervention commonly used in the treatment of subjects with frozen shoulder symptoms, with limited proven effect. The purpose of this study was to identify the kinematic features of patients with frozen shoulder who are more likely to respond to physical therapy. Thirty-four subjects presenting frozen shoulder syndrome were studied to determine altered shoulder kinematics and functional disability. Subjects received the same standardized treatment with passive mobilization/stretching techniques, physical modalities (i.e. ultrasound, shortwave diathermy and/or electrotherapy) and active exercises twice a week for 3 months. Initially, subjects were asked to perform full active motion in 3 tests: abduction in the scapular plane, hand-to-neck and hand-to-scapula. During the test, shoulder kinematics were measured using a 3-D electromagnetic motion-capturing system. In the initial and follow-up sessions, the self-reported Flexilevel Scale of Shoulder Function (FLEX-SF) was used to determine functional disability from symptoms. Improvement with treatment was determined using percent change in FLEX-SF scores over three months of treatment [(final score-initial score)/initial score x 100,20% improvement and= 20% nonimprovement]. Shoulder kinematics were first analysed for univariate accuracy in predicting improvement and then combined into a multivariate prediction method. A prediction method with two variables (scapular tipping8.4 degrees during arm elevation, and external rotation38.9 degrees during hand to neck) were identified. The presence of these two variables (positive likelihood ratio=15.71) increased the probability of improvement with treatment from 41% to 92%. It appears that shoulder kinematics may predict improvement in subjects with frozen shoulder syndrome. Prospective validation of the proposed prediction method is warranted.

Chang C-W, Shieh S-F, Li C-M, Wu W-T, Chang K-F. Measurement of motor nerve conduction velocity of the sciatic nerve in patients with piriformis syndrome: a magnetic stimulation study. Objective To assess the motor nerve conduction of the sciatic nerve by a magnetic stimulation method in patients with piriformis syndrome. Design Prospective study. Setting An electrodiagnostic laboratory in a university hospital. Participants Twenty-three patients with piriformis syndrome and 15 healthy persons for control. Interventions Not applicable. Main Outcome Measures Motor nerve conduction velocity (MNCV) of the sciatic nerve was measured at the gluteal segment by magnetic stimulation proximally at L5 and S1 roots and distally at sciatic nerve at gluteal fold and recording at the corresponding muscles. Diagnostic sensitivities were measured in the magnetic stimulation method and the conventional nerve conduction, long latency reflex, and needle electromyography studies. Results The mean MNCV of the sciatic nerve ± standard deviation at the gluteal segment in L5 component was 55.4±7.8m/s in patients with piriformis syndrome, which was slower than the mean value of 68.1±10.3m/s obtained in healthy controls ( P =.014). The MNCV of the sciatic nerve in S1 component showed no significant difference between the patients and controls ( P =.062). A negative relation was found between the disease duration and the MNCV values of sciatic nerves in patients with piriformis syndrome ( r =−.68, P Conclusions Magnetic nerve stimulation provides a painless, noninvasive, and objective method for evaluation of sciatic nerve function in patients with piriformis syndrome.

Intracerebral hemorrhage is an unusual complication of autonomic dysreflexia and can be fatal if massive bleeding occurs with brain herniation. We report the case of a man in his midthirties with incomplete tetraplegia who suffered right putaminal hemorrhage during an episode of autonomic dysreflexia. Prompt recognition and removal of the triggering factors of autonomic dysreflexia quickly brought his blood pressure under control and the patient had a favorable functional outcome after rehabilitation. A review of the literature suggests that the location of hemorrhage in autonomic dysreflexia-induced cases is similar to that in the general population. The most common triggering factors are bladder distension in men and labor induction in women. Hemorrhagic stroke can also occur in patients with incomplete spinal cord injury (SCI) who develop autonomic dysreflexia. The role of sympathetic skin response examination is also discussed. This life-threatening complication should be kept in mind in the case of people with SCI.

Background Work-related upper limb amputations account for a significant number of occupational injuries. This study analyzes the nationwide incidence of work-related amputations of upper limbs in Taiwan by using the workers' compensation database. Methods A total of 2,950 cases were retrieved and analyzed from the database of workers' compensatory disability claims between the years 1999 and 2001. Results The cases were workers with an average age of 39.1 years, of whom 23.0% were female, the highest percentage of cases was in the 30–49 age group, but the incidence based on insured population was the highest for those under 20 years old. About 96% of the cases involved finger amputation, and 85% of all amputations were related to common powered machines. The average annual incidence of disability claims due to occupational amputation of upper extremities was 12.5 per 100,000 workers. Claims were most prevalent among manufacturing workers and male workers. The male to female risk ratios ranged from 2.62 for manufacturing workers to 9.05 for transport, storage and communication workers by the Poisson regression analysis. Conclusions Young male manufacturing workers were at high risk of occupational amputation of upper extremities in Taiwan. These results provide an epidemiological base for developing a prevention strategy. Am. J. Ind. Med. 46:649–655, 2004. © 2004 Wiley-Liss, Inc.

To evaluate the chronodispersion and tacheodispersion of F waves in patients with spinal cord injury and to determine whether these parameters are more sensitive than those of standard F waves.F chronodispersion and F tacheodispersion as well as F wave latencies, amplitude, and persistence were measured in tibial nerves of 23 male patients with different scales of spinal cord injury and 23 normal subjects. Spasticity was measured and correlated with F chronodispersion in spinal cord injury patients.F chronodispersion of 6.4 +/- 1.9 msec (mean +/- SD) obtained in spinal cord injury patients was found to be significantly greater than the results of 3.9 +/- 1.6 msec in normal controls (P0.05). F chronodispersion was greater in spinal cord injury patients with complete cord lesion. A positive correlation was found between F chronodispersion and Ashworth Scores in spinal cord injury patients. There were no significant differences in minimal latency, amplitude, persistence of F waves, and F tacheodispersion between spinal cord injury patients and normal subjects.Measurement of F chronodispersion may provide a useful and sensitive electrophysiologic assessment in evaluation of spinal cord injury and serve as an evident tool for differentiating pathologic from normal state motoneuron excitability in spinal cord lesion.

A motor evoked potential (MEP) study with percutaneous magnetic stimulation over the motor cortices and an F-wave study in peripheral nerves were performed to measure spinal cord motor conduction velocity (SCMCV) in 25 patients with herniated disc-induced cervical myelopathy (HDICM). Grading of motor function and assessment of SCMCV were performed before and 2 years after microsurgical discectomy. The results show that functional motor improvement accompanied by an increase in SCMCV occurred in grade I patients with mild neurological impairment after surgery, whereas no definite change was seen in grade II and grade III patients with moderate and severely neurological impairment. This finding suggests that measurement of SCMCV by MEP study with a noninvasive method may provide an objective and quantitative method to assessment of the functional integrity of the spinal motor pathway and that the results of such studies may serve as a predictor in evaluation of surgical outcome in patients with HDICM.

Single nerve lesion or mononeuropathy caused by extrinsic compression of hematoma or hemarthrosis is consistently reported for hemophilic patients. To study the manifestation of peripheral nerve lesions, an extensive nerve conduction study of peripheral nerves and specific nerves in correlation with clinical involvement was carried out on 126 hemophilic patients. We found 24 patients with 34 peripheral nerve lesions. The frequency of nerve lesion positively correlated with the severity of hemophilia (p < 0.01) and increasing age (p < 0.05). Nerve lesions occurred more commonly in lower extremities than in upper extremities. The femoral nerve was most commonly involved. Seven patients were identified to have mononeuropathy multiplex with 2 or more nerve lesions involving more than one extremity. All of these patients had chronic condition. Our findings suggest that mononeuropathy multiplex may occur in hemophilic patients.

Objective: To compare the ventilatory response to hypercapnia and the mouth occlusion pressure measured at 0.1 second following inspiration (P 0.1 ) in hypercapnia between chronic tetraplegic and normal subjects. Design: A case-control study with an uneven sample size for the study of clinical disorders. Setting: Patients were recruited from the outpatient clinic of a rehabilitation department. Participants: Seven normal men and 9 men with tetraplegia who had cervical cord injuries (C5–C8), with a mean injury duration of 9.7 yrs. Interventions: Pulmonary function tests were performed during resting, whereas minute ventilation (V E ) and P 0.1 were measured during CO 2 rebreathing. Results: The maximal voluntary ventilation (MVV), vital capacity (VC), and maximal respiratory muscle strength in the tetraplegic subjects were significantly less than in the normal subjects. Both the ventilatory and P 0.1 responses to hypercapnia were significantly reduced in tetraplegic as compared with normal subjects, but the reductions were eliminated by normalizing with maximal ventilatory performance (MVV or VC) and maximal inspiratory muscle strength (PI max ), respectively. Conclusions: Chronic tetraplegic persons have diminished ventilatory and P 0.1 responses to hypercapnia. Respiratory muscle weakness may be a primary factor contributing to the diminished ventilatory response observed in these patients.

The influence of pulsed magnetic stimulation on denervated muscles was investigated in this study. Of 24 rats divided into three groups for experiment, 8 rats served as control; 16 rats with bilaterally severed sciatic nerves were divided into two groups for different modes of stimulation. Magnetic stimulation with a high power output that induced an intensive contraction of muscle was applied at one side-denervated gastrocnemius muscle for 1 mo in a group of rats; electric stimulation with high intensity at 6 Hz frequency and 1-ms pulse duration served as a contrast in the other group. Muscular weight, volume, fiber diameter and percentage of fiber types were measured after the experiment. A significant retardation of weight loss in denervated muscles via magnetic stimulation (P < 0.05) was confirmed by observed results. Type II fiber atrophy was retarded in denervated muscles by magnetic stimulation as well as in denervated muscles via electric stimulation. Magnetic stimulation, used as a method that induces muscular activity, was verified in this study as being capable of retarding denervated muscular atrophy. Its benefits of painless stimulation as well as deeply activated muscular contraction could be expected to function as a new model for rehabilitation of paralyzed muscles.

Comparison of sensory nerve conductions in palmar cutaneous branch (PCB) and digit I nerves was applied in 50 patients suspected of having carpal tunnel syndrome (CTS) and 40 healthy persons. The abnormalities were defined as the differences in latencies and sensory nerve conduction velocities (SNCVs) of more than mean plus 2.5 SD of controls. Comparing these 2 sensory nerves, statistical differences were seen in 83.7% (36 of 43 patients) of their sensory latencies and 76.7% (33 of 43 patients) of their SNCVs. This excluded 7 patients who had unobtainable sensory nerve action potentials in digit I nerves. This method may serve as an adjunctive technique in the diagnosis of CTS. Its diagnostic sensitivity was high in comparison with other testing methods.

By using motor evoked potential (MEP) created by transcranial electric stimulation over the motor cortex and F-wave measurement from the peripheral nerve stimulation, it is possible to estimate the spinal cord motor conduction velocity (SCMCV) in the diseased state. Twenty-four patients with spinal cord injury (SCI) between T1 and T11 neurological levels participated in this study. MEP in leg muscle was absent in all neurologically complete paraplegics. In 16 patients with neurologically incomplete SCI, MEP was obtained in 13 patients. The SCMCV estimated from C7 to T12 spinal levels was 32.1 (SD = 9.4) m/s. This was significantly slower than 63.3 (SD = 8.6) m/s in 40 normal controls. This noninvasive, indirect method is measurable, and can provide valuable electrophysiological data in the assessment of motor function in patients with SCI.