Applied Anatomy Study Of Neonatal Brachial Plexus Roots Avulsion Injury

Objectives:To investigate the morphological characteristics of avulsion injury of neonatal brachial plexus root and the reimplantation depth and angle of brachial plexus root after avulsion injury,and the blood supply of brachial plexus were reconstructed by 3-D,which provides the anatomical basis for the diagnosis and treatment of neonatal brachial plexus root avulsion injury.Methods:1.The morphological characteristics of the anterior and posterior roots of the brachial plexus were observed under the operating microscope sxp-1c?10?on 12 neonatal cadavers;2.The reimplantation depth and angle of brachial plexus root were observed on 10 spinal cord histological samples of neonatal brachial plexus;3.The blood supply of brachial plexus root were studied by ink perfusing 1 neonatal cadaver and latex perfusing 6neonatal cadavers.4.The blood supply of brachial plexus were reconstructed by 3-D by poly?vinyl alcohol?-bismuth oxide perfusing 2 neonatal cadavers.Results:1.The diameters of neonatal brachial plexus anterior roots were less than the posterior roots,which are more prone to avulsion injury.The diameter,the initial length and the distance from the source of the dura mater to the confluence of the nerve trunk of the C₅-C₇posterior root on the right side were less than the left side.2.The minimum distance of neonatal brachial plexus anterior roots to midline was 1.62 mm at C₅,while the maximum was 2.54mm at T₁.Inversely,the distance between the origin of neonatal brachial plexus posterior roots and the midline of the spinal cord gradually decreased,being the maximum 3.22 mm at C₅ and minimum 1.86 mm at T₁.3.Neonatal ventral root separate angle and anterior branches angle were smaller than those of adults,and the difference between the anterior root angle greater anterior root separation angle compared with adults,the differences were in the angle more than 10 degrees,the branches were angle less than 10 degrees;the difference of C₅-C₆ anterior root separate angle with the anterior branches of adult angle is bigger,the average gap between newborns was 20 degrees,the average adult does not exceed 20 degrees;4.Histological results showed that C₅-T₁ segment the gray matter and white matter ratio,shape and size are different,From the angle of C₅-T₁ implantation to 20 degrees-50 degrees,the depth of implantation,the maximum of C₇ is about 2.50mm,and the minimum of T₁ is only 1.60mm.The distance between anterolateral sulcus and anterior median fissure,the maximum of C₇ is about 1.42mm,and the minimum of T₁is only0.92mm.5.The blood supply of neonatal brachial plexus anterior and posterior roots is derived from the segmental artery of subclavian artery.The blood supply of neonatal brachial plexus nerves were derived from the branch of the subclavian-axillary artery axis.6.The 3-D reconstruction of neonatal brachial plexus nerves and its blood supply can be used to observe the three-dimensional space between the brachial plexus nerves and the blood supply vessels for all-dimensional and multi-angle studies.Conclusion:Compared with the C₅-C₆ to C₇-T₁ nerve root and the right arm to the left arm,the brachial plexus nerve root ofC₅-C₆and right arm is more likely to have root avulsion Considerdue toanatomical factors.Neonatal brachial plexus root avulsion after nerve root to the spinal cord,can choose anterolateral sulcus was 20 degrees below 50 degrees and the anterior median fissure;spinal cord injury side near the midline about 1.60-2.50mm,medial anterior lateral sulcus and anterior median fissure distance is about 1mm.