Normative Data of Nerve Conduction Study of Upper Limb Nerves Among Adults in Sulaimani Province: A Cross-Sectional Study

Abstract

Background 
 Electrodiagnostic studies, which serve as an extension of clinical examination, play an important role in evaluating patients with neuromuscular disorders. Therefore, each electromyography laboratory must have normative data for its population to establish reference values for nerve conduction study (NCS) parameters, and many carefully screened healthy subjects are required.
 Objectives 
 To provide the normative data for a nerve conduction study among adults in Sulaimani province. And evaluate the impact of age, gender, and anthropometric measures on NCS parameters.
 Patients and Methods
 A cross-sectional study was conducted at the electromyography unit of Shahid Dr. Aso Hospital in Sulaimani, Iraq. The study involved 300 healthy participants with an approximately equal proportion of the two genders. Their age ranged from 20 to 60 years. The subjects were enrolled in the study according to specific inclusion criteria after history checking and undergoing neurological examination.
 Results
 The study included 144 (48%) male and 156 (52%) female participants. The DMLs and DSLs of all the tested nerves turned out to be significantly shorter in females. CMAP-As and SNAP-As were considerably higher in females. The MCVs and SCVs of all nerves were markedly faster in females. Also, the median and ulnar FMINLAT results showed to be significantly shorter in females. Aging has led to a significant prolongation of median DML and DSL, reduction in CMAP-A and SNAP-A, and slowing of MCV and SCV. Similar results were obtained for ulnar and radial nerves with different levels of statistical significance. Using Pearson’s correlation, the DML, DSL, and FMINLATs of all the tested nerves showed a significant positive linear correlation with height. 
 Conclusion
 Age and BMI did not show a systematic pattern of influence on any of the NCS parameters, demonstrating variable effects with variable levels of significance. In NCS, applying universally standardized techniques may result in different NCS data to the existing literature regarding latencies, amplitudes, nerve conduction velocities, and F-wave data.