Ulnar Sensory Nerve Conduction Velocities Research Articles

Evaluation of Hand-Arm Vibration Syndrome Owing to Nerve Conduction Study and Cumulative Exposure Index-A 2.5-Year Cohort Study.

This study aims to clarify the relationship between peripheral neuropathy in hand-arm vibration syndrome and cumulative exposure index. 68 participants without symptoms were surveyed. The participants were divided into three groups based on past and current vibration exposure (VE). Comparison among groups according to past VE showed that the median and ulnar sensory nerve conduction velocities and median sensory nerve action potential (SNAP) amplitude were significantly lower in past high and low exposure groups than in the past nonexposure group. Comparison among groups according to current VE showed that the median and ulnar SNAP amplitudes were significantly lower in the current high exposure group than in the current low or nonexposure group. Vibration tool handlers have potential peripheral nerve lesions at a certain stage without subjective symptoms of the finger.

Long-term effects of pancreatic islet transplantation on polyneuropathy in patients with brittle diabetes: A single-center experience.

Pancreatic islet transplantation (ITx) is increasingly used in patients with brittle type 1 diabetes (T1D). If successful, ITx results in insulin-free euglycemia, but its application is limited by a need for lifelong immunosuppression. The aim of this study was to assess the long-term effects of ITx on the occurrence and course of polyneuropathy in a cohort of patients with brittle T1D. In this prospective, single-center study, 13 patients (4 males and 9 females) with brittle T1D had a baseline neurological exam with the calculation of Utah Neuropathy Scale (UNS) and a limited nerve conduction study before ITx, and about yearly after in the patients who achieved insulin independence. Patients were followed for a period of 17 to 133 months. There was no significant difference between UNS and nerve conduction study parameters at baseline and at the end of follow-up, except for significant decreases in peroneal (50.34 ± 6.12 vs. 52.42 ± 6.47 ms, P = 0.005) and ulnar (27.5 ± 2.15 vs. 29.45 ± 2.10 ms, P = 0.009) F-wave latencies and an increase in ulnar sensory nerve conduction velocity (49.98 ± 6.27 vs. 47.19 ± 5.36 m/s, P = 0.04). If successful, ITx has a good long-term safety profile for peripheral nerve toxicity, and a favorable effect on diabetic neuropathy.

Association Between Manual Loading and Newly Developed Carpal Tunnel Syndrome in Subjects With Physical Disabilities: A Follow-Up Study

ObjectiveTo identify the association between body composition and newly developed carpal tunnel syndrome (CTS) and to search for the best probabilistic cutoff value of associated factors to predict subjects with physical disabilities developing new CTS. DesignLongitudinal. SettingUniversity-affiliated medical center. ParticipantsSubjects with physical disabilities (N=47; mean age ± SD, 42.1±7.7y). InterventionsNot applicable. Main Outcome MeasuresMedian and ulnar sensory nerve conduction velocity (SNCV) were measured at the initial and follow-up tests (interval >2y). Total and regional body composition were measured with dual-energy x-ray absorptiometry at the initial test. Leg lean tissue percentage was calculated to delineate each participant's manual loading degree during locomotion. Leg lean tissue percentage is the lean tissue mass of both legs divided by body weight. ResultsBased on median SNCV changes, we divided all participants into 3 groups: subjects with bilateral CTS (median SNCV value <45m/s plus a normative ulnar SNCV value >37.8m/s) in the initial test (n=10), subjects with newly developed CTS in the follow-up test (n=8), and subjects without additional CTS in the follow-up test (n=27). Eight of 35 subjects not having bilateral CTS initially developed new CTS (8.8% per year; mean follow-up period, 2.6y). Leg lean tissue percentage was associated with the probability of newly developed CTS (adjusted odds ratio, .64; P<.05). Subjects with a leg lean tissue percentage >12% were less likely to have developed new CTS at the follow-up test (sensitivity, .75; specificity, .85; area under the curve, .88; P<.005). ConclusionsLeg lean tissue percentage may be useful for early identification of developing new CTS in subjects with physical disabilities. Therefore, a preventive program for those subjects at risk can start early.

Should neurophysiological criteria for diagnosis of carpal tunnel syndrome be different for patients with diabetes mellitus?

Background: Diabetes mellitus (DM) is a common association with CTS. The gold standard of diagnosis is nerve conduction studies. Boston Carpal Tunnel Questionnaire (BCTQ) is a self applied questionnaire which evaluates the severity of the symptoms and the functional status in CTS.Objectives: We aimed to find out whether accepted neurophysiological criteria for diagnosis of CTS are applicable to patients with DM.Patients and method: Following neurophysiological parameters were measured in clinic patients with DM; median motor distal latency (MMDL), median and ulnar-sensory distal latency difference (MUDLD), median and ulnar sensory nerve conduction velocity difference (MUNCVD). Distal latencies were compared with normal values available for the same laboratory. Patients with BCTQ score of zero was considered as asymptomatic and others; symptomatic. Percentages of subjects fulfilling different neurophysiological criteriato diagnose CTS were calculated i.e. MMDL ≥ 4.5 m/s, median sensory nerve conduction velocity (MSNCV) ≥40 m/s, MUNCVD ≥ 10 m/s, MUDLD ≥ 1 m/s.Results: Among the 70 normal controls the mean MMDL was3.36 ms ± 0.53. In of 51 (females 68.6%, mean age 59.86 years) consented patients 102 hands were tested. There were 61 asymptomatic hands with zero BCTQ. Mean ± SD of MMDL in themwas 4.30 ± 1.01. According to the above neurophysiological criteria 31.14%, 60.6%, 16.3% or 32.78% will be misdiagnosed as CTS. Among the symptomatic subjects mean MMDL was4.92 ± 1.74. The corresponding proportions according to neurophysiological criteria for symptomatic patients were 48.87%, 48.87, 32% or 60.97%.Conclusion: Accepted neurophysiological criteria will over-diagnose CTS in patients with DM. Different diagnostic criteria should be used in them to confirm CTS. Background: Diabetes mellitus (DM) is a common association with CTS. The gold standard of diagnosis is nerve conduction studies. Boston Carpal Tunnel Questionnaire (BCTQ) is a self applied questionnaire which evaluates the severity of the symptoms and the functional status in CTS. Objectives: We aimed to find out whether accepted neurophysiological criteria for diagnosis of CTS are applicable to patients with DM. Patients and method: Following neurophysiological parameters were measured in clinic patients with DM; median motor distal latency (MMDL), median and ulnar-sensory distal latency difference (MUDLD), median and ulnar sensory nerve conduction velocity difference (MUNCVD). Distal latencies were compared with normal values available for the same laboratory. Patients with BCTQ score of zero was considered as asymptomatic and others; symptomatic. Percentages of subjects fulfilling different neurophysiological criteriato diagnose CTS were calculated i.e. MMDL ≥ 4.5 m/s, median sensory nerve conduction velocity (MSNCV) ≥40 m/s, MUNCVD ≥ 10 m/s, MUDLD ≥ 1 m/s. Results: Among the 70 normal controls the mean MMDL was3.36 ms ± 0.53. In of 51 (females 68.6%, mean age 59.86 years) consented patients 102 hands were tested. There were 61 asymptomatic hands with zero BCTQ. Mean ± SD of MMDL in themwas 4.30 ± 1.01. According to the above neurophysiological criteria 31.14%, 60.6%, 16.3% or 32.78% will be misdiagnosed as CTS. Among the symptomatic subjects mean MMDL was4.92 ± 1.74. The corresponding proportions according to neurophysiological criteria for symptomatic patients were 48.87%, 48.87, 32% or 60.97%. Conclusion: Accepted neurophysiological criteria will over-diagnose CTS in patients with DM. Different diagnostic criteria should be used in them to confirm CTS.

Somatosensory evoked potentials and sensory nerve conduction velocities in the thoracic limb of mallard ducks (Anas platyrhynchos)

To develop a clinically applicable technique for recording cord dorsum potentials (CDPs) following stimulation of the radial and ulnar nerves and establish reference values for radial and ulnar sensory nerve conduction velocities (SNCVs) in the wings of ducks. 8 clinically normal adult female mallard ducks (Anas platyrhynchos). Radial and ulnar compound nerve action potentials (CNAPs) and CDPs were recorded following distal sensory nerve stimulation. The CDPs were recorded from the interarcuate space between the last cervical vertebra and the first thoracic vertebra. Surgical dissection and transection of the brachial plexus in 1 anesthetized duck were performed to identify nerve root location and confirm functional loss of nerve conduction assessed by loss of the CDP. Radial and ulnar CNAPs and CDPs were consistently recorded in all birds. Median radial SNCV was 38.3 m/s (range, 36.0 to 49.0 m/s), and ulnar SNCV was 35.3 m/s (range, 28.0 to 40.0 m/s). Surgical transection of the brachial plexus resulted in complete loss of the CDP. Measurement of radial and ulnar SNCV or CDP is feasible in isoflurane-anesthetized mallard ducks. The CDP accurately reflects sensory nerve conduction through the brachial plexus. Assessment of brachial plexus function in mallard ducks via evaluations of SNCVs and CDPs may have application for diagnosis of traumatic injuries to the brachial plexus, evaluation of neuropathies associated with exposure to toxic chemicals, and assessment of the efficacy of interventions such as brachial plexus nerve blockade.

P22.19 What is normal? the effects of age and gender on nerve conduction studies

Background: The normal values of nerve conduction studies are extremely important to differentiate abnormal situations. Aim: We wanted to revise normal values and compare the results in between different age and gender groups. Methods: In this study, 120 people (240 hands) aged between 15 and 74 who had no complaints, prior surgery or trauma of upper extremities underwent nerve conduction studies concerning median and ulnar nerves with standard methods. The parameters used were antidromic median sensory nerve conduction velocity (SNCV) between wrist-Ist, wrist-IIIrd digit, wrist-palm segmet; ulnar SNCV between wrist-Vth digit, motor nerve conduction between wrist and elbow for median and ulnar nerves and sensory nerve action potential amplitudes (SNAP), interpeak latency difference. Skin temperature was controlled. All NCVs adjusted to 35.5 C arbitrarily which was found to be highest degree among the examined cases.The parameters were statistically analysed, compared between age and gender groups. Group I consisted of patients aged 15–49, Group II 50–74. Results: The amplitude differences of both sensory and motor action potentials in between age and gender groups were the most impressive ones. When age groups were compared all amplitudes were smaller in the group II (p = 0.000). In females all SNAPs were larger in amplitude than males (p = 0.000). Although there were some NCV differences between male and female groups, most of them were minor and did not persist in different age groups. The NCV differences between age groups were statistically significant disclosing a slowing of NCV in group II. This change was statistically much more prominent and in females (p = 0.000). Conclusion: Even the nerve conduction velocity studies are very simple tests compared to recent sophisticated electrophysiologic techniques, they are used more widely than any other in daily practise. It should be kept in mind that all normal values highly differ according to age and gender.

Interexaminer Repeatability of Antidromic Ulnar Sensory Nerve Conduction Velocity Measurements

Schuhfried O, Angst M, Herceg M, Paternostro-Sluga T. Interexaminer repeatability of antidromic ulnar sensory nerve conduction velocity measurements. Objective To determine the interexaminer repeatability of the ulnar antidromic sensory nerve conduction velocity (NCV). Design Test-retest design. Based on a randomization list of various combinations and sequences from 2 of a total of 3 examiners, the measurement was repeated within half an hour by a second examiner blinded to the results of the first examiner. Setting Outpatient department. Participants Twenty-four consecutive healthy subjects (mean age, 38y). Interventions Not applicable. Main Outcome Measures The intraclass correlation coefficient (ICC) and the coefficient of repeatability (CR) were determined for the below elbow to wrist (BE-to-W), above elbow to below elbow (AE-to-BE), and axilla to above elbow (AX-to-AE) segments. Results The ICC was .42 for the BE-to-W, .15 for the AE-to-BE, and −.05 for the AX-to-AE segment. The CR was 12.2m/s for the BE-to-W, 16.2m/s for the AE-to-BE, and 21.4m/s for the AX-to-AE segment. Conclusions During the assessment of the antidromic sensory NCV of the ulnar nerve, a moderate amount of interexaminer variability must be taken into account for the BE-to-W segment. More proximally, an extremely large amount of interexaminer variability must be taken into account. This calls into question the usefulness of the antidromic ulnar sensory NCV for the AX-to-AE and AE-to-BE segments.

手指のしびれと環指の知覚神経活動電位

Median and ulnar sensory nerve conduction velocities and amplitudes were measured orthodromically on the ring finger in 10 normal hands and in 64 hands with numbness (31 hands with carpal tunnel syndrome (CTS), 16 hands with cubital tunnel syndrome (CubTS), 8 hands with paresthesia due to cervical spondylosis (CS) and 9 hands with diabetic neuropathy (DN)). Of 31 hands with CTS, 13 hands had slow conduction velocities (35.6±7.3m/s) and 18 hands had no sensory nerve action potential (SNAP) in the median nerve. Of 16 hands with CubTS, 12 hands had no SNAP and 4 had normal ulnar nerve conduction velocities. Nine hands with DN had low amplitudes and slow conduction velocities in both nerves. Eight hands with CS had normal SNAPs in both nerves. We concluded that measurement of SNAP of the ring finger is easy and useful for diagnosing numbness in hands.

Studies of peripheral nerve conduction velocities in vibrating tool operators

Vibrating tools such as chain-saws, rock-drills, grinders and tie-tampers have been widely used in many kinds of industries in Japan, causing vibration syndrome among the operators. As is well-known, the syndrome includes disorders of the peripheral circulation in the hands, e.g. Raynaud's phenomenon, and of the peripheral and central nervous systems. As the result of preventive countermeasures to the syndrome during the last decade, the picture of the syndrome has been partly changing especially for the patients among the state forestry workers; for example, the prevalence of the peripheral nerve disorders has been relatively increasing compared with that of Raynaud's phenomenon. Peripheral nerve disorders such as numbness, paresthesia and hypesthesia in the upper limbs tend to be usually cumulative and irreversible. The disorders are very important problem of vibration syndrome from the standpoint of treatment and prevention, though there are only a few reports of the study on the disorders using electrophysiological methods. In order to make objectively clear the peripheral nerve disorders, 236 male vibrating tool operators (= Group V) were examined. The following nerve conduction velocities were measured: (1) Maximal motor nerve conduction velocities (MCV) of the median and ulnar nerves in the forearm. (2) Sensory nerve conduction velocities (SCV) of the median and ulnar nerves in the forearm and palm. (3) Residual latency (RL) of the median and ulnar nerves. Besides, working conditions and complaints relevant to vibration syndrome were examined by using questionnaires. MCVs, SCVs and RLs that were outside of mean +/- 2 S.D. of the control group (= Group C), consisting of 30 healthy men, were evaluated as abnormal. The obtained results led to the following conclusions: (1) All MCVs, SCVs and RLs of Group V were significantly less than those of the control group. In Group V, prevalence of the abnormality in each of forearm SCVs was higher than that in each of MCVs of the corresponding nerves. (2) The difference between the median and ulnar SCV in the palm and the respective SCV in the forearm of each subject was significantly greater for Group V than Group C. (Palm-forearm difference) (3) The difference between the forearm and palmar SCV of the ulnar nerve and the respective velocities of the median nerve was statistically greater for Group V than for Group C. (Ulnar-median difference) (4) Ulnar SCV in the palm of Group V was significantly related to the total operating hours of vibrating tools. (5) There was no significant relation between all the nerve conduction velocities and the white finger attack. But a significant relation was noticed between the prevalence of the abnormal values of ulnar SCV in the palm and the peripheral circulatory function score computed from the data of nail press test and cold immersion test.