The evaluation of motor neuron pool by CMAP scan in polio survivors and clinical correlations

Poliomyelitis (PM) is a generalized disorder. After a stabilized interval, post-polio syndrome ( PPS) may develop in some PM survivors (PS) with new muscle weaknesses, pain and fatigue.This study aimed to explore the electroneurophisiological (ENF) changes in the asymptomatic segments of PS cases using CMAP Scan derived parameters and to determine those heralding the development of PPS. We recruited 19 PM survivors (PS) and 21 controls. CMAP Scans were recorded from asymptomatic thenar and hypothenar muscles. CMAP Scan parameters, including returners, and MScanFit were analyzed. After one year follow-up, PPS patients were determined according to March of Dimes Criteria. The results were ALSo compared with those of ALS patients of (n=35) in a previous study. For maximum CMAP amplitudes and MScanFit MUNE, there were no significant differences between PS and control groups, but values elicited in ALS group were significantly lower p< 0,016. PS group's results situated between those of control and ALS groups for most of the CMAP scan parameters. median nerve,excitability parameters in PS were higher than those of the controls p< 0,016. median and ulnar step size parameters, step number and step% in PS were ALSo significantly higher p< 0,016. ulnar returner% and mean returner% of PPS group (n=9) were significantly higher than stabil PS group p< 0,05 showing fair discriminating powers in ROC analysis (AUC 0,804 and 0,839; respectively). CMAP Scan may uncover insidious MU loss and reinnervation in PM. ulnar returner% and mean returner% may be promising for predicting the development of PPS.