Cubital fossa
Encyclopedia
The cubital fossa is the triangular area on the anterior view of the elbow
of a human or other hominid animal. It is colloquially known as the "elbow pit".
When the radial nerve is included, one can also use the mnemonic for lateral to medial: "Really Need Beer To Be At My Nicest". When the radial nerve is excluded, one can use the mnemonic TAN, for "Tendon Artery Nerve".
The ulnar nerve
is also in the area, but is not in the cubital fossa; it occupies a groove on the posterior aspect of the medial epicondyle
of the humerus.
Several veins are also in the area (for example, the median cubital vein
, cephalic vein
, and basilic vein
) but these are usually considered superficial to the cubital fossa, and not part of its contents.
measurements, the stethoscope
is placed over the brachial artery in the cubital fossa. The artery usually runs medial to the bicepital tendon. The brachial pulse may be palpated in the cubital fossa also just medial to the tendon.
The area just superficial to the cubital fossa is often used for venous
access (phlebotomy
). A number of superficial veins can cross this region. It may also be used for the insertion of a peripherally inserted central catheter
.
Historically, when (venous) blood-letting was practiced, the bicipital aponeurosis
(the ceiling of the cubital fossa) was known as the "grace of God" tendon because it protected the more important contents of the fossa (i.e. the brachial artery and the median nerve).
Elbow
The human elbow is the region surrounding the elbow-joint—the ginglymus or hinge joint in the middle of the arm. Three bones form the elbow joint: the humerus of the upper arm, and the paired radius and ulna of the forearm....
of a human or other hominid animal. It is colloquially known as the "elbow pit".
Boundaries
- superior (proximal) boundary - an imaginary horizontal line connecting the medial epicondyle of the humerusMedial epicondyle of the humerusThe medial epicondyle of the humerus, larger and more prominent than the lateral epicondyle, is directed a little backward. In birds, where the arm is somewhat rotated compared to other tetrapods, it is called ventral epicondyle of the humerus....
to the lateral epicondyle of the humerusLateral epicondyle of the humerusThe lateral epicondyle of the humerus is a small, tuberculated eminence, curved a little forward, and giving attachment to the radial collateral ligament of the elbow-joint, and to a tendon common to the origin of the Supinator and some of the Extensor muscles. In birds, where the arm is somewhat... - medial (ulnar) boundary - lateral border of pronator teres muscle
- lateral (radial) boundary - medial border of brachioradialisBrachioradialisBrachioradialis is a muscle of the forearm that acts to flex the forearm at the elbow. It is also capable of both pronation and supination, depending on the position of the forearm...
muscle - apex- it is directed inferiorly, and is formed by the meeting point of the lateral and medial boundaries
- superficial boundary (roof)- skin, superficial fascia containing the median cubital vein, the lateral cutaneous nerve of the forearm and the medial cutaneous nerve of the forearm, deep fasciaDeep fasciaDeep fascia is a layer of fascia which can surround individual muscles, and divide groups of muscles into compartments....
reinforced by the bicipital aponeurosisBicipital aponeurosisThe bicipital aponeurosis is a broad aponeurosis of the biceps brachii which is located in the cubital fossa of the elbow and separates superficial from deep structures in much of the fossa....
(a sheet of tendon-like material that arises from the tendon of the biceps) - deep boundary (floor)- brachialis and supinator muscles
Contents
The cubital fossa contains four main vertical structures (from lateral to medial):- The radial nerveRadial nerveThe radial nerve is a nerve in the human body that supplies the upper limb. It supplies the medial and lateral heads of the triceps brachii muscle of the arm, as well as all 12 muscles in the posterior osteofascial compartment of the forearm and the associated joints and overlying skin.It...
is in the vicinity of the cubital fossa, located between brachioradialisBrachioradialisBrachioradialis is a muscle of the forearm that acts to flex the forearm at the elbow. It is also capable of both pronation and supination, depending on the position of the forearm...
and brachialis muscles. It is often but not always considered part of the cubital fossa. - The biceps brachii tendonTendonA tendon is a tough band of fibrous connective tissue that usually connects muscle to bone and is capable of withstanding tension. Tendons are similar to ligaments and fasciae as they are all made of collagen except that ligaments join one bone to another bone, and fasciae connect muscles to other...
- The brachial arteryBrachial arteryThe brachial artery is the major blood vessel of the arm.It is the continuation of the axillary artery beyond the lower margin of teres major muscle. It continues down the ventral surface of the arm until it reaches the cubital fossa at the elbow. It then divides into the radial and ulnar arteries...
. The artery usually bifurcates near the apex (inferior part) of the cubital fossa into the radial arteryRadial arteryIn human anatomy, the radial artery is the main blood vessel, with oxygenated blood, of the lateral aspect of the forearm.-Course:The radial artery arises from the bifurcation of the brachial artery in the cubital fossa. It runs distally on the anterior part of the forearm...
(superficial) and ulnar arteryUlnar arteryThe ulnar artery is the main blood vessel, with oxygenated blood, of the medial aspect of the forearm. It arises from the brachial artery and terminates in the superficial palmar arch, which joins with the superficial branch of the radial artery...
(deeper) - The median nerveMedian nerveThe median nerve is a nerve in humans and other animals. It is in the upper limb. It is one of the five main nerves originating from the brachial plexus....
When the radial nerve is included, one can also use the mnemonic for lateral to medial: "Really Need Beer To Be At My Nicest". When the radial nerve is excluded, one can use the mnemonic TAN, for "Tendon Artery Nerve".
The ulnar nerve
Ulnar nerve
In human anatomy, the ulnar nerve is a nerve which runs near the ulna bone. The ulnar collateral ligament of elbow joint is in relation with the ulnar nerve. The nerve is the largest unprotected nerve in the human body , so injury is common...
is also in the area, but is not in the cubital fossa; it occupies a groove on the posterior aspect of the medial epicondyle
Medial epicondyle
Medial epicondyle can refer to:* Medial epicondyle of the humerus * Medial epicondyle of the femur...
of the humerus.
Several veins are also in the area (for example, the median cubital vein
Median cubital vein
In human anatomy, the median cubital vein is a superficial vein of the upper limb. It connects the basilic and cephalic vein and is often used for venipuncture . It lies in the cubital fossa superficial to the bicipital aponeurosis.There exists a fair amount of variation of the median cubital vein...
, cephalic vein
Cephalic vein
In human anatomy, the cephalic vein is a superficial vein of the upper limb.It communicates with the basilic vein via the median cubital vein at the elbow and is located in the superficial fascia along the anterolateral surface of the biceps brachii muscle.Superiorly the cephalic vein passes...
, and basilic vein
Basilic vein
In human anatomy, the basilic vein is a large superficial vein of the upper limb that helps drain parts of hand and forearm. It originates on the medial side of the dorsal venous network of the hand, and it travels up the base of the forearm and arm...
) but these are usually considered superficial to the cubital fossa, and not part of its contents.
Clinical aspects
During blood pressureBlood pressure
Blood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...
measurements, the stethoscope
Stethoscope
The stethoscope is an acoustic medical device for auscultation, or listening to the internal sounds of an animal body. It is often used to listen to lung and heart sounds. It is also used to listen to intestines and blood flow in arteries and veins...
is placed over the brachial artery in the cubital fossa. The artery usually runs medial to the bicepital tendon. The brachial pulse may be palpated in the cubital fossa also just medial to the tendon.
The area just superficial to the cubital fossa is often used for venous
Vein
In the circulatory system, veins are blood vessels that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated blood to the heart...
access (phlebotomy
Phlebotomy
Phlebotomy is the process of making an incision in a vein.It is associated with the following concepts:* Venipuncture, the practice of collecting venous blood samples* The main practice of a phlebotomist, an individual trained to draw blood...
). A number of superficial veins can cross this region. It may also be used for the insertion of a peripherally inserted central catheter
Peripherally inserted central catheter
A peripherally inserted central catheter is a form of intravenous access that can be used for a prolonged period of time...
.
Historically, when (venous) blood-letting was practiced, the bicipital aponeurosis
Bicipital aponeurosis
The bicipital aponeurosis is a broad aponeurosis of the biceps brachii which is located in the cubital fossa of the elbow and separates superficial from deep structures in much of the fossa....
(the ceiling of the cubital fossa) was known as the "grace of God" tendon because it protected the more important contents of the fossa (i.e. the brachial artery and the median nerve).