Obesity Affects Median Nerve Conduction - A Study in Armed Forces Individuals.

Background: Obesity, a growing public health concern, is associated with various disorders. Studies have suggested obesity as an independent risk factor that influences the prevalence of carpal tunnel syndrome (CTS) among active workers. The present study is an attempt to establish relationship between median nerve conduction velocity and obesity in people who do not have any other contributory factor for CTS other than obesity. CTS is the commonest entrapment neuropathy where the median nerve is compressed. Methods: The study was conducted in 15 obese subjects with Body Mass Index (BMI)>30 (group III) and 15 overweight subjects with BMI between 25&29.9 (group II) and 15 control subjects with BMI <25 (group I). The subjects were personnel from armed forces. Their body density was estimated using hydro-densitometry and the body fat percentage was calculated from density. The distal motor latency (DML) and the sensory conduction velocity (SCV) across the wrist on stimulation of median nerve at wrist 3cm proximal to distal crease were assessed in all subjects. Results: The mean values of DML in group I, II, and III were 3.52±0.25 ms, 3.50±0.30 ms and 3.65±0.20 ms respectively. Mean value of SCV among these groups were 48.99±3.23 m/s, 49.32±3.35 m/s and 48.69±4.00 m/s. Conclusion: No relationship could be established between BMI and DML as well as BMI and SCV. The relationship between percentage body fat and DML and SCV also found to be statistically insignificant. However, there was a correlation between BMI and body fat percentage. Carpal tunnel syndrome is uncommon even in obese armed forces personnel, which might be due to their regular body and hand exercise thereby having increased tone in hand muscles.

Effects of Electro Acupuncture on the Sensory Nerve Conduction Velocity / 日本温泉気候物理医学会雑誌

Electro-nerve stimulation is an Electro Acupuncture (EA) method that is clinically applied to treat periphral neuropathy. We examined the effects of electro-nerve stimulation on the Sensory Nerve Conduction Velocity (SCV). The changes in SCV caused by applying electro-nerve stimulation to the peripheral nerves were measured.<br>Al-Hz EAT was applied for 10min to the right upper arms of healthy adult volunteers (n=12). The SCV in the median nerve and the skin temperature of the forearm were measured before and after the application. The SCV and skin temperature were found to exhibit asignificant decrease after the electricity was turned on. Therefore, we concluded that EAT caused the decrease in skin temperature of the forearm and, as a result, lowered the SCV in the median nerve.

A study on the Statistical Distribution and Testing of Variation Indicies at the Small Area Variation Analysis / 예방의학회지

OBJECTIVES: The Study of Small Area Variation(SAV) is most interesting issue in the health care researches. Most studies of SAV have been concluded the existences of variation on the basis of the magnitude of variation without statistical testing. But it is difficult to explain the existence of variation with this way because variation indicies are easily influenced by several parameters and also their distribution are skewed. So, it needs for the study to investigate the distribution of these indices and develop the statistical testing model. METHODS: This study was planned to analyze on the distribution of variation indices such as Extremal Quotient(EQ), Coefficient of Variation(CV), Systematic Component of Variation(SCV) and compare the statistical power among indicies. The simulations was performed on the basis of several assumptions and compared to the empirical data. RESULTS: Main findings can be summarized as follows. 1. If other conditions are constant, the more number of regions, the larger 95 percentile of EQ. But under same situation, 95 percentile of CV and SCV were slightly decreased. 2. If the size of regional population or utilization rate were increased, 95 percentile of all statistics were decreased. Also in the cases of small population size and low utilization rate, 95 percentiles of EQ showed various change contrast to the little change of CV. 3. If the difference at the size of regional population were increased, 95 percentiles of EQ and SCV were increased contrast to the little difference of CV 4. If the utilization rate were increased, 95 percentiles of all indicies were increased. But under the same difference of utilization rate, the power of CV and SCV were increased comparing to no change of the power of EQ. 5. Usually the power of EQ were lower than that of CV or SCV and it is similar between CV and SCV. CONCLUSIONS: Therefore, we suggest that in selecting the variation indicies at the SAV, CV or SCV are superior than EQ in terms of significance level and power.