Measurement of the Area and Circumference of the Leg Preliminary Results of a New Method for Estimating Leg Muscle Trophism in Fetuses with Open Lumbosacral Spina Bifida

Objective To standardize a new technique to evaluate the fetal leg muscle trophism by measuring the area and circumference, and comparing this technique between normal and fetuses with open lumbosacral spina bifida (SB). Methods Observational cross-sectional study was carried out on pregnant women with 26 weeks who were divided into two groups: Group I-fetuses with diagnosis of open lumbosacral SB; Group II-normal fetuses (control). In fetuses with SB, subjective evaluation of the lower limbs was performed (muscle echogenicity and leg movements). To estimate the leg muscle trophism, the measurement of the area and circumference of the leg were standardized, and the reproducibility of this method was performed. Results Thirty-one fetuses with open lumbosacral SB and 51 normal fetuses were evaluated. The measurements of the area and circumference of the leg proved to be highly reproducible (intraclass correlation coefficient-ICC > 0.95). The leg area and circumference measurements were statistically lower in the SB group than in the control group (p < .001). When subjective ultrasound assessment demonstrated hypotrophy of the lower limbs, the measurements of the area and circumference of the leg were statistically lower when compared to normal fetuses (p < .001). Fetuses with open SB with abnormal lower limb movements had lower measurements of the area and circumference of the leg than fetuses with normal movements (p < .001). Conclusion A new technique for estimating fetal leg muscle trophism was standardized, which proved to be highly reproducible and was able to show the difference between normal and fetuses with SB.

Automated summary

A new technique was standardized to evaluate fetal leg muscle trophism, showing significant differences between normal and fetuses with open lumbosacral spina bifida through measurements of leg area and circumference. The method proved to be highly reproducible, with lower measurements observed in fetuses with SB compared to the control group, and particularly in cases with abnormal lower limb movements.