Citations
To investigate the effects of real repetitive peripheral magnetic stimulation (rPMS) treatment compared to sham rPMS treatment on pain reduction and functional recovery of patients with acute low back pain.
A total of 26 patients with acute low back pain were randomly allocated to the real rPMS group and the sham rPMS group. Subjects were then administered a total of 10 treatment sessions. Visual analogue scale (VAS) was assessed before and after each session. Oswestry Disability Index (ODI) and Roland-Morris Disability Questionnaire (RMDQ) were employed to assess functional recovery at baseline and after sessions 5 and 10.
Real rPMS treatment showed significant pain reduction immediately after each session. Sustained and significant pain relief was observed after administering only one session in the real rPMS group. Significant functional improvement was observed in the real rPMS group compared to that in the sham rPMS group after sessions 5 and 10 based on ODI and after session 5 based on RMDQ.
Real rPMS treatment has immediate effect on pain reduction and sustained effect on pain relief for patients with acute low back pain compared to sham rPMS.
Citations
To investigate the effects of repetitive peripheral magnetic stimulation (rPMS) on the vastus lateralis (VL) in the early stage after hip replacement surgery.
Twenty-two patients who underwent hip replacement after proximal femur fracture were included in this study. After hip surgery, the experimental group was applied with 15 sessions of 10 Hz rPMS over the VL 5 times per week for 3 weeks, while the control group took sham stimulation. All patients were also given conventional physical therapy. The VL strength was measured with the root mean square (RMS) value of the VL with surface electromyography technique. The ratio of RMS values between fractured and unfractured legs and tandem stand test were used to assess standing balance. Usual gait speed was measured to evaluate gait function. Pain in two groups was assessed with visual analog scale (VAS).
Both RMS value of the VL and the ratio of RMS values after rPMS were significantly improved (p<0.05). Also, tandem standing time and usual gait speed in rPMS group were dramatically increased (p<0.05). However, no significant difference in VAS was found between the two groups after 3 weeks.
rPMS on the VL improved muscle strength, standing balance and gait function in the early stage after hip surgery. Therefore, rPMS could be applied to patients who cannot take electrical stimulation due to pain and an unhealed wound.
Citations
To compare overall physical function, including gait speed and peripheral nerve function, between diabetic chronic kidney disease (CKD) patients and nondiabetic CKD patients and to investigate the association between gait speed and peripheral nerve function in CKD patients.
Sixty adult CKD patients (35 with and 25 without diabetes), who received maintenance hemodialysis (HD), were included in this study. Demographic data, past medical history, current medical condition and functional data—usual gait speed, vibration perception threshold for the index finger (VPT-F) and the great toe (VPT-T), activity of daily living (ADL) difficulty, and peripheral neuropathy (PN) along with the degree of its severity—were collected and compared between the two groups. Correlations between the severity of PN and the impairment of other functions were identified.
Diabetic CKD patients showed significantly slower gait speed (p=0.029), impaired sensory function (VPT-F, p=0.011; VPT-T, p=0.023), and more frequent and severe PN (number of PN, p<0.001; severity of PN, p<0.001) as compared to those without diabetes. Usual gait speed had a significant negative correlation with the severity of PN (rho=−0.249, p=0.013). By contrast, VPT-F (rho=0.286, p=0.014) and VPT-T (rho=0.332, p=0.035) were positively correlated with the severity of PN. ADL difficulty was comparatively more frequent in the patients with more severe PN (p=0.031).
In CKD patients with maintenance HD, their gait speed, sensory functions, and peripheral nerve functions were all significantly impaired when they have diabetes, and the severity of PN was negatively correlated with their gait speed, sensory function, and ADL function. Adverse effects of diabetes impacted physical performance of CKD patients. The physical disability of those patients might be attributable to PN and its severity.
Citations
To investigate the effect of intravenous infusion of peripheral blood mononuclear cells (mPBMC) mobilized by granulocyte-colony stimulating factor (G-CSF) on upper extremity function in children with cerebral palsy (CP).
Fifty-seven children with CP were enrolled. Ten patients were excluded due to follow-up loss. In total, 47 patients (30 males and 17 females) were analyzed. All patients' parents provided signed consent before the start of the study. After administration of G-CSF for 5 days, mPBMC was collected and cryopreserved. Patients were randomized into two groups 1 month later. Twenty-two patients were administered mPBMC and 25 patients received normal saline as placebo. Six months later, the two groups were switched, and administered mPBMC and placebo, respectively. Quality of Upper Extremity Skills Test (QUEST) and the Manual Ability Classification System (MACS) were used to evaluate upper motor function.
All subdomain and total scores of QUEST were significantly improved after mPBMC and placebo infusion, without significant differences between mPBMC and placebo groups. A month after G-CSF, all subdomain and total scores of QUEST were improved. The level of MACS remained unchanged in both mPBMC and placebo groups.
In this study, intravenously infused mPBMC showed no significant effect on upper extremity function in children with CP, as compared to placebo. The effect of mPBMC was likely masked by the effect of G-CSF, which was used in both groups and/or G-CSF itself might have other neurotrophic potentials in children with CP.
Citations
To assess the reliability of quantitative muscle ultrasonography (US) in healthy subjects and to evaluate the correlation between quantitative muscle US findings and electrodiagnostic study results in patients with carpal tunnel syndrome (CTS). The clinical significance of quantitative muscle US in CTS was also assessed.
Twenty patients with CTS and 20 age-matched healthy volunteers were recruited. All control and CTS subjects underwent a bilateral median and ulnar nerve conduction study (NCS) and quantitative muscle US. Transverse US images of the abductor pollicis brevis (APB) and abductor digiti minimi (ADM) were obtained to measure muscle cross-sectional area (CSA), thickness, and echo intensity (EI). EI was determined using computer-assisted, grayscale analysis. Inter-rater and intra-rater reliability for quantitative muscle US in control subjects, and differences in muscle thickness, CSA, and EI between the CTS patient and control groups were analyzed. Relationships between quantitative US parameters and electrodiagnostic study results were evaluated.
Quantitative muscle US had high inter-rater and intra-rater reliability in the control group. Muscle thickness and CSA were significantly decreased, and EI was significantly increased in the APB of the CTS group (all p<0.05). EI demonstrated a significant positive correlation with latency of the median motor and sensory NCS in CTS patients (p<0.05).
These findings suggest that quantitative muscle US parameters may be useful for detecting muscle changes in CTS. Further study involving patients with other neuromuscular diseases is needed to evaluate peripheral muscle change using quantitative muscle US.
Citations
Neuromyelitis optica spectrum disorders (NMOSD) is a demyelinating syndrome of the central nervous system. This case report describes a 31-year-old woman whose electromyography revealed radiculopathy in the left L5-S1 spinal segment without anatomical abnormalities on lumbosacral magnetic resonance imaging (MRI). She was diagnosed with NMOSD based on gadolinium contrast whole spine and brain MRI and anti-aquaporin-4 antibody findings. Her peripheral nervous system might have been damaged during the early course of NMOSD. Therefore, it is necessary to consider NMOSD for patients who have radiculopathy in electromyography if lumbosacral MRI shows no abnormalities.
Citations
To investigate the effect of pulsed radiofrequency (PRF) applied proximal to the injured peripheral nerve on the expression of tumor necrosis factor-α (TNF-α) in a neuropathic pain rat model.
Nineteen male Sprague-Dawley rats were used in the study. All rats underwent chronic constriction injury (CCI) procedure. After 7 days of CCI, withdrawal frequency of affected hind paw to mechanical stimuli and withdrawal latency of affected hind paw to heat stimulus were measured. They were randomly divided into two groups: group A, CCI group (n=9) and group B, CCI treated with PRF group (n=10). Rats of group B underwent PRF procedure on the sciatic nerve. Withdrawal frequency and withdrawal latency were measured at 12 hours, and 7 days after PRF. Immunohistochemistry and Western blot analysis were performed using a TNF-α antibody.
Before PRF, withdrawal frequency and withdrawal latency were not different in both groups. After PRF, withdrawal frequency decreased and withdrawal latency prolonged over time in group B. There was significant interaction between time and group for each withdrawal frequency and withdrawal latency. Group B showed decreased TNF-α immunoreactivity of the spinal cord and sciatic nerve at 7 days.
PRF applied proximal to the peripheral nerve injury is potentially helpful for the reduction of neuropathic pain by neuromodulation of inflammatory markers.
Citations
Myotonic dystrophy (MD) is the most common adult muscular dystrophy characterized by multi-systemic clinical manifestations involving the brain, smooth muscle, cardiovascular and endocrine systems. However, peripheral arterial occlusive disease (PAOD) is an uncommon presentation of MD type 1 (DM1), which has not been reported in recent literature. A 53-year-old female, previously confirmed as DM1, presented with vague claudication of both lower limbs. The diagnosis of PAOD based on results of ankle-brachial index, ultrasonography, and abdominal computed tomography angiography studies was followed by aortobifemoral artery bypass surgery. Although the arterial patency was restored after the operation, she did not recover from post-operative respiratory complications. Screening of PAOD is necessary for DM1 with general risk factors of occlusive arteriopathy. However, surgery should be reserved for the most severe cases.
Electrical shock can result in neurological complications, involving both peripheral and central nervous systems, which may present immediately or later on. However, delayed neurological complications caused by low-voltage electric shock are rarely reported. Here, a case of a man suffering from weakness and aphasia due to the delayed-onset of the peripheral nerve injury and ischemic stroke following an electrical shock is presented. Possible mechanisms underlying the neurological complications include thermal injury to perineural tissue, overactivity of the sympathetic nervous system, vascular injury, and histological or electrophysiological changes. Moreover, vasospasms caused by low-voltage alternating current may predispose individuals to ischemic stroke. Therefore, clinicians should consider the possibility of neurological complications, even if the onset of the symptoms is delayed, and should perform diagnostic tests, such as electrophysiology or imaging, when patients present with weakness following an electric injury.
Citations
To assess the prevalence of peripheral neuropathy in patients with rheumatoid arthritis (RA) having neuropathic symptoms, and to investigate the relationship between electrophysiological findings of peripheral neuropathy and clinical findings of RA.
Patients with a clinical diagnosis of RA and who had tingling or burning sensation in any extremity were electrophysiologically examined for evidence of peripheral neuropathy. Study parameters, including age, gender, laboratory parameters, duration of RA, and medication, were recorded. The symptoms and signs of neuropathy were quantified with the neuropathy symptom score, and the functional statuses of these patients were assessed.
Out of a total of 30 RA patients, 10 (33%) had peripheral neuropathy: 2 had bilateral carpal tunnel syndrome (CTS), 5 had unilateral CTS, 1 had sensory polyneuropathy, and 2 had motor-sensory polyneuropathy. The mean ages of the patients with and without peripheral neuropathy were 69.4 and 56.5 years, respectively (p<0.05). A significant relationship was found between peripheral neuropathy and anti-cyclic citrullinated peptide (anti-CCP) antibody. However, no relationship was found between peripheral neuropathy and the type of medication, RA duration, the patients' functional status, neuropathic symptoms, erythrocyte sedimentation rate, and C-reactive protein values.
Neuropathic symptoms are common in RA patients, and it is difficult to distinguish peripheral neuropathy symptoms from those of arthritis. Patients with RA, particularly elderly patients and anti-CCP antibody positive patients who complain of neuropathic symptoms should undergo electrophysiological examination.
Citations
Medial antebrachial cutaneous (MABC) nerve injury associated with iatrogenic causes has been rarely reported. Local anesthesia may be implicated in the etiology of such injury, but has not been reported. Two patients with numbness and painful paresthesia over the medial aspect of the unilateral forearm were referred for electrodiagnostic study, which revealed MABC nerve lesion in each case. The highly selective nature of the MABC nerve injuries strongly suggested that they were the result of direct nerve injury by an injection needle during previous brachial plexus block procedures. Electrodiagnostic studies can be helpful in evaluating cases of sensory disturbance after local anesthesia. To our knowledge, these are the first documented cases of isolated MABC nerve injury following ultrasound-guided axillary brachial plexus block.
Citations
Method: Nerve conduction studies were performed in 23 patients with chronic renal failure. We not only measured distal latencies, amplitudes, and conduction velocities of median and ulnar motor nerves but also measured same parameters of radial sensory nerves at both upper limbs. In case of pateints with suspected peripheral polyneuropathy, we checked peripheral nerves at one lower limb. The results of nerve conduction studies and the frequency of cubital tunnel syndrome or carpal tunnel syndrome were compared between arteiovenous fistula side and non-arteiovenous fistula side.
Results: The amplitudes of median motor, ulnar motor nerves and radial sensory nerve in arteiovenous fisula side are statistically lower than those in non-arteiovenous fisula side (p<0.05). In the 14 patients with peripheral polyneuropathy, the difference is also statistically significant between two sides (p<0.05). Compared arteiovenous fisula side with non-arteiovenous fisula side, the frequency of cubital tunnel syndrome or carpal tunnel syndrome was not different between two sides.
Conclusion: Arteiovenous fisula may damage to the peripheral nerve in patients with chronic renal failure. (J Korean Acad Rehab Med 2003; 27: 85-89)
Method: Prospectively, total 40 patients with non-insulin dependent diabetes mellitus were included in the study. NCS was performed on median, ulnar, posterior tibial, deep peroneal, superficial peroneal, and sural nerves. Distal latency and conduction velocity (CV) of compound muscle action potential (CMAP), distal latency and amplitude of sensory nerve action potential (SNAP) were used as parameters of NCS. Multiple linear regression analysis were used to analyze the relations of HbA1c and parameters of NCS, after adjustment for age, height, weight, and disease duration of diabetes mellitus.
Results: HbA1c level had an inverse relation to CV of median motor nerve (β=1.272, p<0.01), ulnar motor nerve (β=1.287, p<0.01), posterior tibial nerve (β=0.982, p<0.05), and deep peroneal nerve (β=1.449, p<0.05).
Conclusion: This study indicates that HbA1c level was inversely related to motor nerve CV, and that sustained hyperglycemia may be involved in demyelination of motor nerves. Analysis of motor nerve CV related to HbA1c is expected to be useful in the follow-up or efficacy study of diabetes mellitus neuropathy as baseline data. (J Korean Acad Rehab Med 2003; 27: 80-84)
Organophosphate is known to damage both the peripheral and central nervous system. We report a case of organophosphate-induced peripheral polyneuropathy with myelopathy. A 46 years old woman who had ingested a large amount of insecticide (organophosphate) was transported to our hospital. Following medical treatment, she was transferred to the Department of Rehabilitation Medicine 1 month later. Upon admission to rehabilitation medicine, the patient was quadriplegic with markedly decreased muscle tone and strength. Electrodiagnostic examination revealed low amplitude of sensory nerve action potential (SNAP), unevokable compound muscle action potential in distal muscles and abnormal spontaneous activities with needle
electromyography, which were compatible with peripheral polyneuropathy. Three months later, motor and sensory function of upper extremities were normalized. The muscle tone of lower extremity increased to Ashworth grade II. Follow-up electrodiagnostic examination revealed normalization of SNAP and disappearance of spontaneous activities, but somatosensory evoked potential which were initially normal, revealed prolonged P40 latencies in the lower extremities. These electrophysiological findings were thought to result from the spinal cord lesion and correlated with clinical findings. We diagnosed the patient as peripheral polyneuropathy with delayed myelopathy induced by organophosphate. (J Korean Acad Rehab Med 2002; 26: 113-116)
Objective: To investigate the effect of peripheral nerve stretching on motor evoked potentials (MEP) as a method of facilitation.
Methods: Twenty three normal healthy volunteers were enrolled. Transcranial magnetic stimulation (TMS) was applied to the contralateral scalp at 7 cm lateral to Cz using 90 cm round coil. Intensity of stimulation was adjusted to 90% of maximal stimulation intensity. Recording was done on the abductor pollicis brevis muscle in three different conditions; firstly resting state, secondly voluntary contraction of abductor pollicis brevis muscle, and lastly with stretching of median nerve. The onset latency and amplitude were obtained and compared between three conditions.
Result: The amplitude of MEP was significantly increased in the condition with muscle contraction and peripheal nerve stretching compared with resting state. The latency was shortened in the condition with muscle contraction with statistical significance and with peripheral nerve stretching without significance.
Conclusion: We concluded that stretching of peripheral nerve can be used as a method of facilitation of MEP. This method is considered to be useful especially for the patients with motor paralysis or poor cooperarion for voluntary contraction.
Objective: The purpose of this study was to determine whether quantitative sensory test can be used as a screening test of peripheral polyneuropathy in patients with diabetes mellitus, and to evaluate the severity of peripheral polyneuropathy in patients with diabetes mellitus using quantitative sensory test.
Method: We performed nerve conduction study to right upper and left lower extremity of the patients. Quantitative sensory test was performed using TSA-2001 thermal sensory analyser on right thenar and left foot dorsum in both diabetic and control groups.
Results: 1) The warm sense and heat pain threshold were higher, the cold sense and cold pain threshold were lower in diabetic group than age-matched control group (p<0.05). 2) The warm sense and heat pain threshold were higher, the cold sense and cold pain threshold were lower in diabetic group than young-aged control group (p<0.05). 3) As nerve conduction study results were severe, the cold sense threshold in right thenar were decreased (p<0.05).
Conclusion: Quantitative sensory study in patients with diabetes mellitus are sensitive to identify neuropathic change; thus, they would be used as the screening method of diabetic peripheral polyneuropathy.
A 45-year-old man with a long history of nephrotic syndrome presented with low back pain and progressive weakness of both legs for one day. Physical examination showed an acutely ill-appearing patient with a loss of both femoral artery pulses. Immediate digital subtraction angiography of abdominal aorta revealed total occlusion of the distal abdominal aorta. Transvascular embolectomy using urokinase was undertaken 6 hours later. Digital subtraction angiography after embolectomy revealed both common ilicac arteries to be patent with good distal flow. Electrodiagnostic examinations (post embolectomy 5th and 45th day) revealed peripheral polyneuropathy of both lower extremity. Anticoagulation therapy was continued and the patient was discharged several months later. During this period, there was improvement in both lower limbs from power of grade 1 to 4 except for both ankle dorsiflexors which had not recovered.
We report a rare case of peripheral ischemic polyneuropathy of both lower extremities as the result of acute abdominal aortic occlusion.
Objective: The purpose of this study was to determine the difference of temperature effects on the nerve conduction variables and to obtain correction factors for temperature in demyelinated and normal peripheral nerves.
Method: The compound muscle action potentials (CMAPs) were recorded with wrist stimulation during cooling and warming in 10 control subjects and 13 subjects with demyelinating neuropathies. The temperature of cooling and warming were 18oC and 40oC, respectively. The time of cooling and warming were 60 minutes and composed of successive 4 sessions of 15 minutes. The skin temperature of thenar area, latency, amplitude, duration, and area of CMAPs were measured before and after each session of 15 minutes of cooling or warming.
Results: The time constants of parameters of CMAPs were of higher tendency in cooling than in warming. The time constants of latency of CMAP were higher in subjects with demyelinating neuropathy than in controls (p<0.05): 33.3⁑4.0 minutes versus 27.2⁑2.2 minutes in cooling; 30.0⁑7.8 minutes versus 19.6⁑3.3 minutes in warming. The temperature correction factor of latency of CMAPs was 0.23⁑0.03 msec/oC in control and 0.33⁑0.06 msec/oC in subjects with demyelinating neuropathies (p<0.05).
Conclusion: When studying a subject with demyelinating neuropathies, we should warm the extremity for more sufficient time than in normal subject, or may applicate a differenct temperature correction factors.
Objective: To investigate waveform changes of compound muscle action potentials (CMAPs) related to voluntary muscle contraction and alteration of muscle length and to evaluate the effect of peripheral neuropathy on temporal and spatial summations of CMAPs.
Method: The influence of voluntary muscle contraction and alteration of muscle length on CMAP was studied in 37 median nerves of 21 patients with median neuropathy.
Results: In patients with no apparent axonopathy, temporal summation was partially disturbed without significant change of spatial summation. Shortening of muscle length or voluntary contraction produced a physiologic improvement of spatial and temporal summations. There was a decrease in temporal and spatial summations, more prominent in temporal summation, with lengthening of the muscle. In axonopathy, spatial summation was markedly deteriorated with partial reduction of temporal summation. Spatial summation was not affected by the change of muscle length or voluntary contraction. Temporal summation was improved by muscle shortening or voluntary contraction and was decreased by muscle lengthening.
Conclusion: Peripheral neuropathy has an effects on physiological spatial and temporal summations of CMAPs. Temporal summation is preferentially decreased in cases without axonopathy. When axonopathy is apparent, spatial summation is profoundly disturbed with partial reduction of temporal summation.
Objective: To investigate the role of tendon reflex test in the diagnosis of diabetic peripheral neuropathy.
Method: Patellar tendon reflex (PTR) and achilles tendon reflex (ATR) were recorded in forty six diabetic patients and thirty seven normal adults by delivering tendon taps with an electric reflex hammer. Forty six diabetic patients were divided into two groups based on nerve conduction study and diabetic neuropathy score: group 1 consisted of nineteen patients with peripheral neuropathy, group 2 consisted of twenty seven patients without peripheral neuropathy. Multiple regression equations using latency as a variable dependent on age and height were used and upper crossing of the 3 standard deviation level with regression on height and age was considered abnormal.
Results: Mean latencies of PTR and ATR were prolonged in the diabetic patients in comparison with the controls (p<0.01) and were prolonged in group 1 compared to group 2. In group 1, PTR was abnormal in 14 cases (sensitivity: 73.6%, specifity: 88%) and ATR was abnormal in 13 cases (sensitivity: 68.4%, specifity: 85.1%). In group 2, PTR was abnormal in 3 cases and ATR was abnormal in 4 cases.
Conclusion: Tendon reflex test would be a valuable supplement to conventional nerve conduction studies for detection of diabetic peripheral neuropathy, especially in the proximal segment.
Objective: To evaluate peripheral hemodynamics using the doppler ultrasound in the diabetic patients.
Method: We measured mean blood flow velocity (MBFV), resistance index (RI), pulsatility index(PI) in the dorsalis pedis artery (DPA), posterior tibial artery (PTA), and radial artery (RA) from 18 normal controls (n=36), 17 diabetes patients without neuropathy (n=34), and 21 diabetes patients with neuropathy (n=42) by use of Angiodine 2 Doppler system operating at 8 MHz frequency.
Results: MBFV of all the examined arteries increased significantly in the diabetes with neuropathy in comparison to controls and the diabetes without neuropathy (p<0.05). RI and PI of DPA and PTA decreased significantly in the diabetes with neuropathy in comparison to controls and diabetes without neuropathy (p<0.05). The blood flow velocity profile was changed from triphasic to monophasic pattern in the diabetes with neuropathy in DPA and PTA.
Conclusion: The Doppler ultrasound is considered as a useful tool for screening change of peripheral blood flow in the diabetic patients with neuropathy.
Objective: To determine whether electrophysiologic findings of mild diabetic neuropathy in elderly patients is due to age or diabetic mellitus itself.
Method: Electrophysiologic examination was performed in patients with diabetes mellitus and in normal control subjects over the age of 60. Electrophysiologic results of 55 diabetic neuropathy patients and the normal control subjects were compared.
Results: 1) Effect of age or diabetes mellitus on the electrophysiologic parameters: In normal controls over 60 years of age the motor and sensory parameter demonstrated a significant difference compared to those under 60. In diabetic patients, motor and sensory parameters demonstrated a significant difference compared to the control group.
2) Interaction of age and diabetes mellitus: Concerning the effect of age, significant differences were observed in amplitude in both motor and sensory responses. Regarding the effect of diabetes, significant differences were observed in latency or velocity in the motor and sensory nerves compared to the control group.
Conclusion: Eletrophysiologically, prolonged latency is the result of the diabetic process, whereas decreased amplitude is thought to be due to the effect of age. In diagnosing mild diabetic neuropathy in elderly patients, we should consider the differential effects of age itself and diabetes mellitus.
Objective: The dorsomedial cutaneous nerve (DMCN) to the great toe is a branch of the medial dorsal cutaneous nerve, which originates from the superficial peroneal nerve. The objective of this study is to standardize the electrodiagnostic technique, and to investigate the usefulness of dorsomedial cutaneous nerve (DMCN) conduction study in patients with peripheral neuropathy.
Method: Sixty two legs in 31 normal adults and 56 legs in 28 patients with the clinical signs and symptoms as well as electrodiagnostic evidences of peripheral neuropathy were evaluated with the DMCN conduction study. The stimulating electrode was placed over the lateral 1/3 between medial and lateral malleoli and the active electrode was placed over 12 mm medial and 10 mm proximal to the extensor hallucis longus tendon over the 1st metatarsophalangeal joint.
Results: The mean values of DMCN conduction study in normal adults were 2.95⁑0.47 msec for onset latency, 3.58⁑0.43 msec for peak latency, 6.67⁑2.87μV in amplitude, and 12.96⁑1.17 cm for distance from active electrode to stimulation point. There were statistically significant differences between normal and patients groups in all parameters except the distance.
Conclusion: A method for DMCN conduction study was introduced which could be used as a valuable technique for the early evaluation of peripheral neuropathy.
Objective: To determine the prevalence, location, and risk factors for the peripheral nerve entrapments of upper extremity among the crutch or cane users.
Method: We performed the clinical and electrodiagnostic assessments of both upper extremities in 43 crutch or cane users and 49 able-bodied controls.
Results: The prevalence for the nerve entrapment of upper extremity among the crutch or cane users was 27.9% by the clinical criteria and 86.0% by the electrodiagnostic criteria. Electrodiagnostically, the median nerve entrapment was 76.7%, and the ulnar nerve entrapment was 72.1% among the crutch or cane users. The carpal tunnel was the most common site for the entrapment. Body weight, duration of disability, and duration of crutch or cane use were found to be significantly correlated with the emtrapments of median nerve, whereas duration of crutch or cane use alone was significantly correlated with the entrapments of ulnar nerve.
Conclusion: The peripheral nerve entrapments of upper extremity is associated with the chronic crutch or cane use and the preventive strategies need to be developed for the patients with risks.
The influence of voluntary muscle contraction and alteration of muscle length on compound muscle action potential (CMAP) was studied in 20 healthy volunteers. The CMAPs were evoked by a supramaximal stimulation and recorded by a surface electrode array. Onset latencies were not significantly changed regardless of the muscle length and contraction. On shortening of the muscle there was a decrease in an area and duration of CMAP with no significant changes in an amplitude. During muscle contractions, there was an increase in amplitude and a decrease in area and duration. On a lengthening of the muscle with relaxation, the amplitude of CMAP decreased with an increased area and duration. During a voluntary contraction, there was a decrease in amplitude, area, and duration. The results are considered due to a peripheral factor such as an alteration of temporal or spatial summation rather than a central mechanism. We conclude that in nerve conduction studies, it is important to monitor the finger position and muscle relaxation to differentiate the waveform changes from the muscle length or contraction and those from the nerve lesions.
Dysfunction of the autonomic nervous system is reported to occur at an incidence of 20% to 40% in diabetes. The clinical symptoms include orthostatic hypotension, vomiting, diarrhea, bladder dysfunction, male impotence, sweating, etc. Two simple noninvasive tests, sympathetic skin response (SSR) and R-R interval variation (RRIV), were used to assess autonomic functions. We performed SSR and RRIV on the diabetic patients and controls. The patients were classified into 4 groups (group I: without peripheral neuropathy or dysautonomia, group II: with dysautonomia only, group III: with peripheral neuropathy only, group IV: with both peripheral neuropathy and dysautonomia). We also tried to correlate their clinical dysautonomic symptoms and the results of nerve conduction studies (NCS) and of SSR and RRIV.
The subjects of this study were 82 diabetic patients, 20 to 73 years old with the mean age of 53, and 12 controls.
Latency, amplitude, and loss of SSR all showed a significant difference in relation to the dysautonomic symptoms. The loss of SSR in the foot showed a remarkable difference in group I.
In groups III and IV, three RRIVs (Valsalva ratio, E:I ratio, 30 : 15 ratio) showed a significant decrease compared with the control group, and in group II, only the 30:15 ratio showed a statistically significant decrease.
In conclusion, the changes in SSR and RRIV were significantly associated with the dysautonomia. Among these, loss of SSR in the foot and decrease in the 30 : 15 ratio were useful parameters for early detection of diabetic autonomic neuropathy without peripheral neuropathy.
Pain, numbness, and weakness in the upper extremity are the common problems among wheelchair users. The prevalence of nerve injury of the upper extremity in the wheelchair users has been reported variously by many authors in other nations. To determine the prevalence, location, and risk factors of upper extremity peripheral nerve entrapment among wheelchair users, we performed clinical and electrodiagnostic assessments on both upper extremities of wheelchair users (n=49) and able-bodied controls (n=49).
The prevalence of nerve entrapment of the upper extremity among the wheelchair users was 15.6% according to clinical criteria, and 46.9% according to electrodiagnostic criteria. Electrodiagnostically, median nerve entrapment was identified in 28.6% of tested cases, and ulnar nerve entrapment was identified in 22.4% of tested cases among wheelchair users. The carpal tunnel was the most common site of nerve entrapment. The duration of wheelchair use was found to be correlated negatively with median wrist to palm and wrist to digit sensory conduction velocity, whereas age correlated positively with distal median and ulnar motor latency.
Peripheral neuropathy constitutes a rare clinical manifestation in the neurofibromatosis. Eleven cases of peripheral neuropathy associated with the neurofibromatosis have been reported. We report a sensorymotor peripheral neuropathy in 2 cases of neurofibromatosis.
Quantitative analysis of abnormal spontaneous activities, motor unit action potentials and interference patterns were recorded in 55 subjects with traumatic peripheral nerve injury to understand the changes of electromyographic signals.
We analyzed amplitudes of fibrillation potentials and positive sharp waves at rest, amplitude, duration, spike duration and polyphasicity of motor unit action potentials at minimal contraction, and the root mean square(RMS), and mean rectified voltage (MRV) at maximal contraction.
The amplitudes of fibrillation potentials and positive sharp waves had negative correlations with the duration of peripheral nerve injury but the amplitudes of motor unit action potentials, RMS, and MRV had positive correlations.
Therefore electromyographic evaluation could be used for the estimation of the duration of peripheral nerve injury.
The effect of electrical nerve stimulation are controversial because of the inconsistent variables of stimulating current and electrophysiologic study. The purposes of this study are to reconfirm the electrophysiolgic changes by electrical stimulation of the peripheral nerve that had been reported in 1993, and to monitor how long they will be maintained. In this study, the following conditioning stimulations were applied to 20 healthy volunteers; interferential current(frequency: 80∼100 Hz, intensity: 27∼34 mA) on the sacral paraspinal area. The H reflex, the F response, and the somatosensory evoked potential(SEP) of the tibial nerve were evaluated as the electrophysiologic study before, immediately after, 30 minutes, 60 minutes, and 120 minutes after the above conditioning stimulation. The following results were obtained;
1) Latencies of the H reflex, the F response and the SEP(P1), and the F wave conduction time, the F wave conduction velocity and the F ratio in the tibial nerve conduction study were increased by conditioning stimulation of the proximal peripheral nerves(P>0.01).
2) Changes of the amplitude of the H reflex, the H/M ratio, and the amplitude(P1N1) of the tibial SEP were not significant in the same conditioning stimulation(P>0.05).
3) Prolongations of the latencies of H reflex, F response and P1 SEP of the tibial nerve were the most significant immediately after conditioning stimulation and sustained for 45 minutes after conditioning on average (P<0.01).
The above results suggest that certain conditional electrical stimulation of the peripheral nerves causes reversible changes in the conduction of the H reflex, the F response and the SEP and they may be inhibitory effect of the proximal conduction via the spinal cord.
Thermography shows skin temperature changes in various conditions of body. Skin temperature changes according to the subcutaneous blood flow which is regulated by the autonomic nervous system. Peripheral neuropathic pain can be influenced by the sympathetic activities which also can change the skin temperature of affected sites.
To evaluate the usefulness of thermography in the detection of peripheral neuropathic pain, authors analyzed thermographic images of 47 cases with peripheral nerve injuries of upper extremities.
The peripheral nerve injuries were confirmed by Electromyographic studies in all of the cases. The peripheral neuropathic pain was present in twenty three cases.
The results show that 97.5% of nerve injury patients with pain and 45.8% of nerve injury patients without pain had abnormal thermograms with a mean temperature changes of △ T=0.99oC △T=0.13oC respectively. Authors conclude that thermography can be an usefal tool for the detection of peripheral neuropathic pain.
The importance of neuropathy in the pathogenesis of foot lesions has been well recognized in diabetes. Blood flow in ischemic limbs has been extensively investigated but the circulation of limbs affected by peripheral neuropathy has received little attention. Some studies on blood flow in peripheral neuropathy have shown a remarkable increase in resting flow, transcutaneous venous oxygen tension, and vascularity, along with loss of the spontaneous variations which occur normally with sympathetic activity of the foot in patients with diabetes. The aim of present study is to find out the effects of somatic and autonomic nervous function in early change of blood flow of foot in diabetic patients. We have studied fifty-one patients of non-insulin-dependent(type II) diabetes with no history of hypertension or diabetic foot ulcers. The evidence of neuropathy was screened by nerve conduction studies and sympathetic skin response of both lower extremities. Blood flow of dorsalis pedis and posterior tibial arteries was measured by portable doppler machine and presented as pressure index (ankle-to-arm systolic pressure ratio). The patients with sympathetic dysfunction showed significant decrease in pressure index compared to normal control and diabetic patients with normal sympathetic function, suggesting that changes of the blood flow occur in diabetic patients with sympathetic dysfunction.