Diagnostic Value of Median Sensory-Ulnar Motor Latency Difference in Mild Carpal Tunnel Syndrome and it’s Comparison with Difference in Sensory and Motor Latencies of Median and Ulnar Nerves

Introduction: Diagnosis of carpal tunnel syndrome (CTS)is based on clinical symptoms, examination findings, andelectrodiagnostic studies. Recent studies have shown theefficacy of median sensory-ulnar motor latency differencewas devised as another way to improve diagnostic accuracyfor mild carpal tunnel syndrome. Current research aimed tostudy diagnostic value of Median sensory ulnar motor latencydifference (MSUMLD) in mild carpal tunnel syndromeand compare it with median-ulnar (MU) sensory and motorlatency differences.Material and methods: 100 hands of CTS were studied andafter a detailed history and physical examination, routine testsand nerve conduction study was done .In mild CTS cases notdetected by routine NCS, MSUMLD was calculated and itssensitivity was compared with MU sensory and motor latencydifference.Results: It was found that Median Ulnar sensory latencydifference had the highest sensitivity.Conclusion: MSUMLD can be added as a new diagnosticparameter in detecting mild CTS with no additional testingalthough it’s sensitivity is less than Median-Ulnar sensorylatency difference

Application of the calculated electrophysiological parameters in early diagnosis of carpal tunnel syndrome

@#Objective: To investigate the application of the calculated electrophysiological parameters in early diagnosis of carpal tunnel syndrome (CTS). Methods: 44 patients (60 hands) with a diagnosis of CTS and 31 healthy volunteers (44 hands) were enrolled. Acquired indicators include median nerve distal motor latency (DML), complex muscle action potential (CMAP) amplitude, conduction velocity (MCV), median nerve sensory nerve action potential (SNAP) amplitude, and conduction velocity (SCV). Then the terminal latency index (TLI), the residual latency (RL), and the difference in peak sensory latencies between the median and ulnar nerves (ΔPSL) were calculated. Results: The two groups were matched in age and gender distribution. The CTS group showed significant difference in SCV, DML, SNAP, and CMAP compared with the control group. The sensitivity, specificity, cutoff value, Youden index, and area under the curve of each indicator are respectively as follows: TLI (0.733, 0.932, 0.622, 0.629, and 0.877), RL (0.750, 0.977, 1.334, 0.727, and 0.907), ΔPSL (0.950, 0.841, 0.150, 0.791, and 0.942), SCV (0.950, 0.796, 56.5, 0.746, and 0.946), DML (0.867, 0.932, 3.55, 0.799, and 0.930), SNAP (0.683, 0.932, 21.68, 0.615, and 0.844), and CMAP (0.683, 0.773, 8.76, 0.456, and 0.758). Conclusion: The calculated electrophysiological parameters have higher sensitivities and specificities relative to a single electrophysiological parameter, which could greatly improve the accuracy of early diagnosis of CTS.

Clinical Correlation Between Nerve Conduction Studies And Neurosonography In Peripheral Neuropathies

BACKGROUND - Peripheral neuropathies are the most common neuromuscular disorder seen by neurologists. Nerve ultrasonography is a recently emerging tool for visualizing the structure, architecture and vascularity of peripheral nerves. OBJECTIVES -To study the Clinical correlation between Nerve conduction studies and Neurosonography in peripheral neuropathies. METHODOLOGY - All patients with peripheral neuropathy were included in the study from February 2016 to January 2018. RESULTS -The most common aetiologies for peripheral neuropathy were diabetes and leprosy. Nerve ultrasound showed corresponding changes in the above conditions. CONCLUSION – Nerve ultrasound is useful in peripheral neuropathy and can complement other diagnostic investigations.

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.

Experimental Study on Carpal Tunnel Syndrome as a Cumulative Trauma Disorder

OBJECTIVE: To study the reaction of tissues in the carpal tunnel after repeated flexion of wrist in order to verify the pathophysiology and pathomechanism of the carpal tunnel syndrome as a cumulative trauma disorder. METHOD: Six groups of adult rabbits (5 rabbits were allocated to each groups) were exposed to repeated contractions of the wrist flexors by the median nerve stimulation at the elbow level for different durations; 2 days, 1 week, 2 weeks, 3 weeks, 4 weeks, and 5 weeks. Histological evaluation, morphometric analysis, and electrophysiological studies were carried out after the stimulation. RESULTS: There were no typical nor consistent findings in the tissues in the carpal tunnel except the median nerve. Inflammatory cell infiltration and edematous changes were noted in the epineurial tissue of median nerve. Decrease of large myelinated fibers and changes of fiber shape were observed in the median nerve. On the morphometric analysis, fiber diameter was smaller in groups of longer exposure duration. Changes were most prominent in 5 weeks group and in the periphery of the nerve fascicle in all the groups. Significant reduction of amplitude and increase of duration of compound muscle action potential were noted on electrophysiological study of the median nerve. CONCLUSION: The authors concluded that repeated experimental wrist flexion could give rise to an injury of the median nerve in the carpal tunnel. Accumulation of microtrauma of median nerve by epineurial edema and direct mechanical compression seems to be the pathomechanism of the carpal tunnel syndrome as a cumulative trauma disorder.

Usefulness of Wrist Crease Stimulation Method in Diagnosis of Carpal Tunnel Syndrome

OBJECTIVE: The previously established method of carpal tunnel syndrome (CTS) diagnosis is relatively troublesome and risk of misleading due to uncertainty of exact distance measurement for stimulation. If we use the wrist crease, an anatomical landmark, there might not be error in length measurement for stimulation at any wrist position. This study was performed to evaluate the wrist stimulation method in the diagnosis of CTS for it's convenience and reducing the errors. METHOD: Seventy healthy adults and sixty-five patients with clinical and electrophysiologic evidence of CTS were studied. Sensory nerve action potentials (SNAPs) in second and fifth digit were recorded antidromically with stimulation at a distance of 14 cm from recording electrode and stimulation at wrist crease. The ratio and difference of distal latency and ratio of amplitude between median and ulnar SNAPs were assessed. RESULTS: The ratio and difference of distal latency and ratio of amplitude in the 14 cm stimulation method were 1.52+/-0.28, 1.59+/-0.91 msec, 1.26+/-0.27 in the right, 1.43+/-0.14, 1.29+/-0.42 msec, 1.18+/-0.20 in the left, respectively in the men patients, and those of women patients were 1.48+/-0.35, 1.43+/-1.04 msec, 1.18+/-0.30 in the right, 1.53+/-0.30, 1.46 0.80 msec, 0.75+/-0.36 in the left. In wrist crease stimulation, those of men patients were 1.72+/-0.39, 1.74+/-0.98 msec, 1.22+/-0.24 in the right, 1.53+/-0.21, 1.31+/-0.46 msec, 1.25+/-0.29 in the left, and those of women patients were 1.67+/-0.46, 1.56+/-1.01 msec, 0.63+/-0.32 in the right, 1.68+/-0.37, 1.56+/-0.82 msec, 0.68+/-0.30 in the left. These results showed a significant positive correlation between the patients group and the control group in two stimulation methods (p<0.001). CONCLUSION: Based on the result of this study, wrist crease stimulation method is a quick and easy procedure, which would be recommended in the early diagnosis of CTS.