Anatomy of the antecubital fossa

VASCULAR ANAESTHESIA

Anatomy of the antecubital fossa

Learning objectives After reading this article you should be able to:

Marco L Baroni

C C

David C Berridge

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define the boundaries of the antecubital fossa describe the contents of the antecubital fossa list the clinical applications of elbow block.

punctured in the fossa and not more proximally, as haematoma formation is more likely as the vessel no longer overlies the humerus and is therefore difficult to compress. The brachial artery can also be used as access for coronary or peripheral angiography, in particular if the patient is unable to lie flat. The superficial veins overlying the antecubital fossa should be reserved for large-bore access in medical emergencies or when other access sites are exhausted. Venous or arterial cannulation in the antecubital fossa or forearm should be avoided in patients with renal failure likely to require arteriovenous fistula formation and is absolutely contraindicated in the presence of a fistula. Elbow blocks can be used for hand or forearm surgery requiring anaesthesia of the median and radial nerves anteriorly and the ulnar nerve posteriorly. Due to the wide separation of the nerves at the elbow and the cutaneous branches which arise proximal to the elbow, blocks in this location are rarely used in practice. One exception would be when only a partial block is achieved with an axillary or supraclavicular brachial plexus block, in which case a targeted approach may be used. Care should be taken when anaesthetizing the ulnar nerve as neuropraxia may result from pressure in the ulnar groove. A

Abstract The antecubital fossa is an important site of both arterial and venous cannulation. Elbow blocks can be used in hand or forearm surgery and to supplement brachial plexus block. This article outlines the essential anatomy of this region and its clinical application.

Keywords Antecubital fossa; cubital fossa; arterial cannulation; elbow block; regional anaesthesia

The antecubital fossa, or cubital fossa as it is also known, is an important site for venous and arterial cannulation, arteriovenous fistula formation and peripheral nerve block, and as such knowledge of its anatomy is essential. The antecubital fossa is triangular in shape with the apex distally. The medial boundary is pronator teres and laterally brachioradialis. The base of the triangle is an imaginary line between the humeral epicondyles. The roof is the deep fascia of the forearm and the floor is comprised predominantly of brachialis, with supinator more laterally (see Figure 1). The contents of the fossa (from medial to lateral) are the median nerve, brachial artery and its venae comitantes, and biceps tendon, with the radial nerve and its posterior interosseous branch lying deep to brachioradialis. The basilic vein and the median cutaneous nerve of the forearm lie on the roof of the fossa medially, overlying the brachial artery. Laterally lie the cephalic vein and the lateral cutaneous nerve of the forearm. There is a variable median cubital vein, draining predominantly into the basilic or cephalic vein. The brachial pulsation is the best palpated medial to the biceps tendon, over the distal humerus. The brachial artery usually divides into its radial and ulnar branches midway down the fossa, although this can be variable. The brachial artery is a reasonable alternative to the radial or ulnar artery at the wrist for placement of an intra-arterial cannula. Care should be taken to ensure that the artery is

Biceps Median nerve Medial cutaneous nerve of forearm

Lateral cutaneous nerve of forearm Radial nerve Brachial artery

Bicipital aponeurosis

Biceps tendon Brachioradialis

Ulnar artery

Pronator teres

Posterior interosseous nerve Radial artery

Figure 1 Left antecubital fossa.

Marco L Baroni FRCS (Gen Surg) is a Consultant Vascular Surgeon at York Hospital, York, UK. Conflicts of interest: none declared. David C Berridge DM FRCS (Eng) (Ed) is a Consultant Vascular Surgeon at Leeds General Infirmary, Leeds, UK. Conflicts of interest: none declared.

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