Median Nerve Conduction Study in different Wrist Position in Normal Persons and the Patients with Diabetes mellitus

ABSTRACT

OBJECTIVE: To determine whether flexion and extension of the wrist joint produce the change in the conduction study of the median nerve in the normal and diabetic patients, and to compare the susceptibility of median nerve compression injury in two groups. METHOD: Thirty healthy adults as control and thirty diabetic patients without carpal tunnel syndrome were studied. The wrist joint was maintained in flexion or extension position for 5 minutes before performing conduction study. The variables used for statistical analysis included the mean difference of amplitude and latency in median motor and sensory responses in neutral, flexion, and extension positions. RESULTS: The results showed that significant differences in the latency and amplitude of median motor and sensory responses between neutral, extension, and flexion of wrist within each group (p<0.01). The differences in the median sensory latency (p<0.01), amplitude (p<0.05) and the change of wrist-palm segmental conduction velocity (p<0.01) were statistically significant between the diabetes and the normal control. CONCLUSION: The results of this study suggest that median nerves are susceptible to compression pressure in diabetic patients. Therefore, the position of the wrist joint should be considered in the median nerve conduction study.