The Comparative Study Of Measurements Of The Length Of Fetal Long Bones:Ultrasound And X-ray And Bare Bones

ObjectiveTo evaluate the correlation with the total length of fetal normal long bones by ultrasound and X-ray and actual length of the bare bones.Method423 cases of fetus (gestational 20-37W) with normal long bones were measured the length of the diaphyses and epimetaphyseal structures (including femoral and humeral) by ultrasound,51 of the fetus (gestational 22-32W)included in the study.The fetus which would be inducing labor were measured the length of the diaphyses and epimetaphyseal structures by ultrasound, and the total length of the long bones were calculated in three days after admission. The fetus after induced labor were measured the length of long bones and bare bones by X-ray and the actual length of the bare bones in 24 hours. These measurement results were analyzed statistically. Some of the bodies after induced labor and some of the bare bones were observed in water in the study.ResultThe morphological characteristics of the diaphyses and epimetaphyseal structures of the long bones intrauterine or vitro by ultrasound and X-ray and the bare bones are basically the same? The measured values of the length of the diaphyses by ultrasound were compared with the measured values of body long bones by X-ray after induced labor,and the later were compared with bare bones length. The difference between the two groups was statistically significant (P<0.05). The measured values of the long bones by X-ray after induced labor were greater than the length of the diaphyses by ultrsound and less than X-ray bare bones length. The measured values of the total length of the long bones by ultrasound, the measured values of bare bones by X-ray both were compared with bare bone length,the difference between the two groups was not satistically significant(P>0.05). Correlation analysis showed there was a strong positive correlation of ultrasound measurement and bare bone length measurement.ConclusionUltrasound can accurately measure length of the diaphyses and epimetaphyseal structures. The measuring results of the three measurements were not entirely consistent, but there was a certain correlation between the three. The length of the fetal long bone diaphyses by ultrasound did not represent the total length of the long bones,and the body X-ray length did not completely reflect the total length of the long bones.While the total length of the long bones including the diaphyses and epimetaphyseal structures were closer to the bare length than the bady X-ray length, which can be more realistically reflect fetal long bone development,and contribute to a more accurate assessment of fetal growth retardation or short long bones.