The High Origin of the Radial Artery (Brachioradial Artery): Its Anatomical Variations, Clinical Significance, and Contribution to the Blood Supply of the Hand

Abstract

Background: This study thoroughly analyzes the anatomic variations of the brachioradial artery (radial artery of high origin) based on the variability of its origin, the presence and types of anastomosis with the brachial artery in the cubital fossa ("cubital crossover" or "cubital connection"), and the pattern of radial recurrent arteries, as well as the vascular territory within the hand.

Material and methods: One hundred and twenty randomly selected, isolated upper limbs fixed in 10% formalin solution were dissected.

Results: The radial artery was found to have a high origin in 9.2% of total number of the limbs: two cases from the axillary artery; nine cases from the brachial artery. Anastomosis between the brachioradial and "normal" brachial arteries in the cubital fossa was also frequently observed (54.6%). The anastomosis ("cubital crossover") was dominant in one case, balanced in three cases, minimal in two cases, and absent in five cases.

Conclusions: The brachioradial artery may originate from the brachial and, less frequently, from the axillary artery. Anastomosis between the brachioradial and "normal" brachial arteries in the cubital fossa may be dominant, balanced, minimal, or absent. A complete radioulnar arch was found more often when the brachioradial artery was present as a variant.

Figure 1

Two variants of the brachioradial artery originating within the axillary fossa. In both cases the brachioradial artery ran anterior to the roots of the median nerve. (a) Brachioradial artery arising from the first part of the axillary artery, just above the medial border of the pectoralis minor muscle. (b) Brachioradial artery branching off the second part of the axillary artery (posterior to the pectoralis minor muscle). AA: axillary artery; AV: axillary vein; BRA: brachioradial artery; LRMN: lateral root of the median nerve; MRMN: medial root of the median nerve; PMa: pectoralis major muscle; PMi: pectoralis minor muscle; UN: ulnar nerve.

Figure 2

Two examples of the brachioradial artery originating in the arm. In both cases the brachioradial artery ran superficially to median nerve. (a) Right female upper limb. Anatomical relations within the medial bicipital groove. The brachioradial artery runs under the bicipital aponeurosis; within the forearm, it continues as the radial artery and occupies a typical position. (b) Left male upper limb. Two arterial trunks (brachioradial and “normal” brachial artery) are visible within the medial bicipital groove. In its course, the brachioradial artery crosses the anterior surface of the median nerve above the intercondylar line of the humerus running to the lateral side of this nerve. BA: brachial artery; BV: basilic vein; BRA: brachioradial artery; CV: cephalic vein; MCNF: medial cutaneous nerve of forearm; MCV: median cubital vein; MN: median nerve; UN: ulnar nerve. White arrowhead shows the origin of the brachioradial artery.

Figure 3

Dominant type of cubital crossover. Anterior view of the cubital fossa, right upper limb. This type of anastomosis between the brachioradial and “normal” brachial artery is characterized by a greater diameter than the brachial segment of the brachioradial artery. The brachioradial artery is present, but hypoplastic. BA: brachial artery; hBRA: hypoplastic brachial segment of the brachioradial artery; MN: median nerve; RA: radial artery. White arrowheads show the cubital crossover.

Figure 4

Balanced type of cubital crossover. This type of the anastomosis is characterized by the similar diameter to that of the brachioradial artery. (a) Anterior view of the cubital fossa, right male upper limb. The cubital crossover (marked by white arrowheads) runs anterior to the distal biceps tendon. (b) Anterior view of the cubital fossa, right female upper limb. In this case the cubital crossover (marked by white arrowheads) runs posterior to the distal biceps tendon. AIA: anterior interosseous artery; aRRA: accessory radial recurrent artery; BA: brachial artery; BRA: brachioradial artery; IUCA: inferior ulnar collateral artery; MN: median nerve; RA: radial artery; RRA: radial recurrent artery; SBRN: superficial branch of the radial nerve; UA: ulnar artery.

Figure 5

Two variants of the cubital crossover. (a) Minimal type of the cubital crossover (marked by white arrowheads). Anterior view of the cubital fossa, right female upper limb. (b) Absence of the cubital crossover. Anterior view of the cubital fossa, left female upper limb. In this case, two separate, unanastomosed arterial trunks ran within the cubital fossa. aRRA: accessory radial recurrent artery; BA: brachial artery; BRA: brachioradial artery; MN: median nerve; RRA: radial recurrent artery.

Figure 6

The most frequent variant of superficial palmar arch observed on the limbs showing a high origin to the radial artery (brachioradial artery). This type may be classified as a complete radioulnar arch in which a well-developed superficial palmar branch of radial (or, respectively, brachioradial) artery contributes to the radial half of the arch. SPA: superficial palmar arch; SPB: superficial palmar branch arising from the brachioradial artery; PL: tendon of palmaris longus muscle; RA: radial artery; UA: ulnar artery; UN: ulnar nerve.

Figure 7

Schematic representation of the arterial remodeling in the developing upper limb between Carnegie stages 17 and 18. (a) Stage 17. Before this stage, the brachial artery branches into the capillary network allowing for the formation of different blood flow pathways. (b) Stage 18. The definitive origin of the radial artery is established at this stage. Also at this stage, the cubital crossover (black arrowheads) between the brachioradial and “normal” brachial artery may be formed in the place of typical origin of the radial artery (both typical origin and high origin of the radial artery have been marked by dotted lines). BA: brachial artery; BRA: brachioradial artery; IA: interosseous artery; MA: median artery; RA: radial artery; UA: ulnar artery. This figure is a modification of the drawing taken from Wysiadecki et al. (2017) under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium.

Figure 8

Selected anatomical variations of the cubital crossover (marked by black arrowheads) between the brachioradial and “normal” brachial artery. (a) Typical course of the radial artery. (b) Dominant type of cubital crossover with hypoplastic preanastomotic part of brachioradial artery. (c) Balanced type. (d) Arterial island (described by Piagkou et al. [42]). (e) Minimal type. (f) No anastomosis between the brachioradial and “normal” brachial artery within the cubital fossa. aRRA: accessory radial recurrent artery; BA: brachial artery; BRA: brachioradial artery; CIA: common interosseous artery; hBRA: hypoplastic preanastomotic part of brachioradial artery; MB: muscular branch; RA: radial artery; RRA: radial recurrent artery; UA: ulnar artery; URA: ulnar recurrent artery.