Brachial artery,radial & ulnar artery,plamar arches

1. BRACHIAL ARTERY

2. The brachial artery is the major blood vessel of the (upper)
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 which run
down the forearm.
The pulse of the brachial artery is palpable on the anterior
aspect of the elbow, medial to the tendon of the biceps, and,
with the use of a stethoscope and sphygmomanometer (blood
pressure cuff) often used to measure the blood pressure.

3. Structure
The brachial artery gives rise to the following branches:
1. Profunda brachii artery (deep brachial artery)
2. Superior ulnar collateral artery
3. Inferior ulnar collateral artery
4. Radial artery (a terminal branch)
5. Ulnar artery (a terminal branch)
6. Nutrient branches to the humerus
It also gives rise to important anastomotic networks of the elbow and
(as the axillary artery) the shoulder.

5. The radial and ulnar arteries are formed by the bifurcation of the
brachial artery within the cubital fossa:
Radial artery – supplies the posterolateral aspect of the forearm. It
contributes to anastomotic networks surrounding the elbow joint and
carpal bones.
The radial pulse can be palpated in the distal forearm, immediately
lateral to the prominent tendon of the flexor carpi radialis muscle.
Ulnar artery – supplies the anteromedial aspect of the forearm. It
contributes to an anastomotic network surrounding the elbow joint.

7. PALMAR ARCHES

8. The superficial palmar arch is formed predominantly by the ulnar artery, with a
contribution from the superficial palmar branch of the radial artery
The arch passes across the palm in a curve (Boeckel's
line) with its convexity downward,
The superficial palmar arch extends more distally than the deep palmar
arch. The connection between the deep and superficial palmar arterial
arches is an example of anastomosis, and can be tested for using Allen's
test.

10. Three common palmar digital arteries arise from the arch,
proceeding down on the second, third, and fourth lumbrical
muscles, respectively. They each receive a contribution from a
palmar metacarpal artery. Near the level of the
metacarpophalangeal joints, each common palmar digital artery
divides into two proper palmar digital arteries.
Four digital branches arise from this palmar arch that supplies the
medial/ulnar 3 1/2 fingers.

11. Deep palmar arch
is an arterial network found in the palm. It is usually formed
mainly from the terminal part of the radial artery, with the ulnar
artery contributing via its deep palmar branch, by an anastomosis.

12. Modified test
In the modified Allen test, one hand is examined at a time
The hand is elevated and the patient is asked to clench their fist for
about 30 seconds.
Pressure is applied over the ulnar and the radial arteries so as to
occlude both of them.
Still elevated, the hand is then opened. It should appear blanched
(pallor may be observed at the finger nails).
Ulnar pressure is released while radial pressure is maintained, and the
colour should return within 5 to 15 seconds.
If color returns as described, Allen's test is considered to be normal. If
color fails to return, the test is considered abnormal and it suggests
that the ulnar artery supply to the hand is not sufficient.[2] This
indicates that it may not be safe to cannulate or needle the radial