Anatomical Variation of High Bilateral Brachial Artery Bifurcation: A Case Report

Abstract

The brachial artery is a continuation of the axillary artery below the inferior border of the teres major muscle. It commonly bifurcates into the radial and ulnar artery low to the neck of the radius. Previous studies have documented variability for upper limb vasculature (9%–18.5%) and variability of brachial bifurcation in the middle of the arm (3–15%). However, there are a lack of cadaver studies that have discussed the effects of a brachial bifurcation in the proximal third of the arm, close to the teres major muscle. During routine anatomical dissections of 24 donors (11 males and 13 females) at Oakland University William Beaumont School of Medicine, it was found that only one donor (female) had a bilateral brachial artery bifurcation in the proximal third of the arm (4.17%). Both right and left arms were measured to be 21cm long, along with brachial artery bifurcation occurring 3cm from the teres major muscle. The bilateral bifurcation may be explained in terms of embryogenesis where there may be a persistence, unusual path, or obliteration of primitive vessels. The variance in the brachial artery bifurcation, especially in the proximal third of the arm, presents heavy clinical considerations. There is a potential that such bifurcations may affect the course of the median, radial, and ulnar nerves. Such variances may complicate surgeries in the brachial region, percutaneous brachial catheterization, and increase the likelihood of inaccurate readings of angiograms and other relevant radiological techniques. Brachial artery proximal bifurcation may also cause individuals to be vulnerable to laceration, which may result in hematomas. A proximal bifurcation of the brachial artery may affect the anastomosis of the ulnar artery with the superior and inferior ulnar collateral arteries and contribute to the excessive hematoma that was observed on the variant donor. The awareness of this clinically significant variation implicates the need for pre‐operative vessel mapping in order to decrease the possibility of iatrogenic injuriesBifurcation of brachial artery on the left arm.Figure 1Bifurcation of brachial artery on the right hand. The blood was determined to be pre‐mortem, leading to a conclusion of a hematoma.Figure 2