Epifisiólise traumática do cotovelo de recém-nascido: do laboratório à prática clínica

Abstract

Distal humerus epiphysiolysis in the neonatal period is a rare lesion, with few published clinical cases. This injury mainly occurs in traumatic, vaginal or emergency cesarean deliveries, when the joint is subjected to a force in hyperextension or rotation of the forearm. Radiographic examination does not accurately confirm this lesion, since the distal humeral epiphysis in this age group is totally cartilaginous. A sonographic study, standardizing the lateral coronal and anterior sagittal sections, was performed in 20 elbows of normal newborns, finding, respectively, a percentage of mean extrusion of the distal humeral epiphysis of 8.95% and 21.66%. An experimental study was carried out to correlate the images of 4 newborn cadaver elbows obtained by ultrasound with the anatomical data found during the autopsy. Two stillbirths had their elbows studied by ultrasound, with the distal epiphyses of the right humerus being marked with echodense metal. The right elbow of each stillborn, when subjected to microtopographic study, confirmed the precise location of the markers. One left elbow of the stillborns was subjected to a varus force and the other left elbow of the second stillborn to a force in hyperextension in order to reproduce epiphysiolysis. The report of the diagnosis of elbow epiphysiolysis in a newborn patient on the 14th day after birth assisted by ultrasound. This examination showed changes similar to the experimental study. Conservative treatment was performed with simple observation and in the late followup, at 18 years of age, the elbow was normal. The results of these studies, both experimental and clinical, proved the accuracy of ultrasonography in visualizing the cartilaginous structures of the newborn's elbow, as well as in accurately identifying the epiphysiolysis and the direction of its deviation when the sonographic sections were systematized.