Arterial Anatomy of the Extremities

13 Arterial Anatomy of the Extremities



Gregory M. Keck, MD , John S. Pellerito, MD, FACR, FSRU, FAIUM , Joseph F. Polak, MD, MPH


The evaluation of arterial disease of the extremities requires knowledge of vascular anatomy. This chapter provides this basic information for the upper and lower extremities. Normal anatomy, common variants, and major collateral routes1–6 are illustrated, primarily by representative arteriograms. The chapter is formatted as a series of captioned illustrations, with the bulk of the instructional material contained within the figure captions.


It is increasingly common for arterial anatomy and pathology to be depicted noninvasively in a clinical setting with computed tomography or magnetic resonance imaging. Image quality with these modalities approaches that of catheter angiography. Because conventional arteriography remains the gold standard, angiographic images are used in this chapter, as they best depict anatomic detail.


The following terms are used to describe extremity anatomy in this chapter. The arm is the portion of the upper extremity between the shoulder and elbow. The forearm is the portion between the elbow and wrist. The thigh is the portion of the lower extremity between the hip and knee, and the calf is the portion between the knee and ankle.



Upper Extremity



Normal Features


The normal arterial anatomy of the upper extremity is depicted graphically in Figure 13-1. Figures 13-2 to 13-5 are detailed arteriographic views of specific regions of the upper extremity arterial tree, beginning at the aorta and extending to the digits. These figures should be reviewed carefully, because their legends provide the instructional content.


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FIGURE 13-1 Arterial anatomy of the upper extremity. Note that the internal thoracic arteries (internal mammary arteries), which are tributaries of the subclavian arteries, are used commonly for coronary artery bypass. The deep palmar arch arises from the radial artery, and the superficial palmar arch arises from the ulnar artery. These arches may or may not communicate with each other. a., artery; aa., arteries; L, left; R, right.


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FIGURE 13-2 The aortic arch connects the ascending aorta (AAo) with the descending aorta (DAo). Three great vessels originate from the aortic arch; the innominate artery (In) originates on the right side of the arch, followed by the left common carotid artery (LCC) and the left subclavian artery (LSu). The innominate artery divides into the right common carotid artery (RCC) and the right subclavian artery (RSu). The right and left vertebral arteries (RV, LV) originate from the subclavian arteries, even though this is not apparent on the right side of this illustration. The internal mammary artery (IM) also arises from the subclavian artery.


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FIGURE 13-3 The subclavian artery (Su) becomes the axillary artery (Ax) at the lateral margin of the first rib. The axillary artery, in turn, becomes the brachial artery (B) after crossing the inferolateral margin of the teres major muscle.3 The thyrocervical (TC) and costocervical (CCT) trunks are noteworthy branches of the subclavian artery, because they may be mistaken for the vertebral artery (V) during duplex examination. The multiple branches that supply the scapular musculature serve as collaterals when the subclavian or innominate arteries are obstructed. CH, circumflex humeral artery; DB, deep brachial artery; DS, dorsal scapular artery; IM, internal mammary artery; SS, subscapular artery.


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FIGURE 13-4 Arterial anatomy (A) and osseous landmarks (B) at the elbow. The brachial artery (B) divides at the elbow, forming the radial (R) and ulnar (U) arteries. The interosseous artery (I) is a branch of the ulnar artery, which in some individuals continues to the wrist. RR, recurrent radial artery; UR, ulnar recurrent artery.


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FIGURE 13-5 The radial artery (R) terminates in the deep palmar arch (dp; black arrows). The ulnar artery (U) terminates in the superficial palmar arch (su; white arrowheads). Communicating vessels usually connect the deep and superficial arches, as shown here. The metacarpal (MC; also called the common palmar digital artery or dorsal metacarpal artery) and proper palmar digital (PD) arteries are branches of the superficial and deep arches.



Anatomic Variants


Many anatomic variants can occur in the arterial tree of the upper extremities. The more commonly encountered variants are presented in Table 13-1.1–3 Familiarity with these variants can prevent confusion and error during duplex examination. An example of an upper extremity anatomic variant is presented in Figure 13-6.


TABLE 13-1 Arterial Variants of the Upper Extremity

































Structure Variant Frequency of Occurrence in the Population (%)
Aortic arch and great vessels Common origin of the right brachiocephalic and left common carotid arteries 22
Left vertebral artery origin directly from the aorta 4-6
Common origin of both common carotid arteries <1
Arm and forearm Radial artery origin from the axillary artery 1-3
Early division of the brachial artery:
1. High origin of the radial artery (Figure 13-6)
2. Accessory (duplicated) brachial artery		 19
Ulnar artery origin from the brachial or axillary artery 2-3
Low origin (5-7 cm below elbow joint) of ulnar artery <1
Persistent median artery 2-4

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FIGURE 13-6 High origin of the radial artery. Arteriograms of the arm (A) and forearm (B) demonstrate a high origin of the radial artery (R; arrows) at the level of the midhumerus. B, brachial artery; I, interosseous artery; U, ulnar artery.



Collateral Routes


Many of the tributaries seen in Figures 13-1 to 13-6 may serve as collaterals when the main arterial trunks of the upper extremity are blocked.


The following is a summary of the more common collateral routes.2



1. Obstruction of the proximal subclavian or brachiocephalic arteries

Related posts:

Normal Cerebrovascular Anatomy and Collateral Pathways Controversies in Venous Ultrasound Nonimaging Physiologic Tests for Assessment of Lower Extremity Arterial Disease The Role of Ultrasound in the Management of Cerebrovascular Disease Duplex Ultrasound Evaluation of the Uterus and Ovaries Extremity Venous Anatomy and Technique for Ultrasound Examination

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Mar 5, 2016 | Posted by in ULTRASONOGRAPHY | Comments Off on Arterial Anatomy of the Extremities

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