Reference values of ultrasonographic measurement of cross-sectional area of the multifidus muscle in children aged 6 to 9 years

This study aimed to provide reference value measures from the cross-sectional area (CSA) of the multifidus muscles in children aged 6 to 9 years old. For this purpose, 41 children (20 boys and 20 girls) were interviewed about their physical exercises practice and submitted to a unilateral ultrasonographic evaluation from the CSA multifidus muscles at rest, in the level of L5, and to an anthropometric evaluation (weight, height and MMI - muscle mass index). An average of CSA from the multifidus was found from 3,11±0,84cm² with no difference between sexes (p=0,37) and between sedentary children and regular exercise practitioners (p=0,68). However, it was detected a positive correlation between the CSA and the age (r=0,75; p<0,01), the weight (r= 0,83), the height (r= 0,75; p<0,01) and the MMI (r=0,54; p<0,01). Thus, the CSA of the multifidus of this study showed a tendency of great dimension according to the age increase, weight, height and MMI.