1. Brachial Plexus + Vascular Supply
Dr. Fadel Naim
Orthopedic Surgeon
Faculty of Medicine
IUG

2. Spinal Nerves
31 pairs of spinal nerves are attached to the spinal cord.
8 cervical
12 thoracic
5 lumbar
5 sacral
1 coccygeal
Each spinal nerve divides into a dorsal and ventral ramus.

3. Spinal Nerves
Spinal nerve
Dorsal
branch
Spinal
nerve
Ventral
branch

4. Spinal Nerve Plexuses
Ventral rami of spinal nerves fuse and form networks with ventral rami of other spinal nerves.
Crossing of fibers
A peripheral nerve may contain axons from several spinal segments.
T2 – T12 do not form plexuses

5. Spinal Nerve Plexuses Cervical plexus Brachial plexus Lumbar plexus
Sacral plexus

6. Brachial Plexus
The brachial plexus is an arrangement of nerve fibres running from the spine (vertebrae C5-T1) through the neck, the axilla, and into the arm.

7. The brachial plexus is responsible for cutaneous and muscular innervation of the entire upper limb
The brachial plexus is also responsible for innervation of deep structures as joints
It has influence over the diameter of blood vessels by sympathetic vasomotor nerves and sympathetic secretomtor supply to the sweat glands

8. “Ramiz Takes Daily Choclate and Bescuit“
Brachial Plexus
One can remember the order of brachial plexus elements by way of the mnemonic,
“Ramiz Takes Daily Choclate and Bescuit“
5 Roots
3 Trunks
3 +3 Divisions
3 Cords
5 Branches

9. CORDS DIVISIONS TRUNKS ROOTS C5 C6 C7 C8 T1
LATERAL
UPPER C6
POSTERIOR
MIDDLE C7 C8
MEDIAL
LOWER T1

10. Roots
The brachial plexus starts in the neck from the anterior rami of spinal nerves C5 - T1 (5th cervical to 1st thoracic spinal cord segments)
These rami are called roots.
Frequently it receives a contribution from one nerve higher or one nerve lower.

11. Trunks
TRUNKS
ROOTS C5
UPPER
The roots continue through the neck and, some of them merge, to form trunks.
C5 and C6 form the upper trunk
C7 continues as the middle trunk
C8 and T1 for the lower trunk C6
MIDDLE C7 C8
LOWER T1

12. Divisions
Each trunk of the brachial plexus divides into anterior and posterior divisions as the plexus passes posterior to the clavicle
Anterior divisions supply anterior (flexor) compartments of the upper limb
Posterior divisions supply posterior (extensor) compartments

13. Cords These six divisions regroup to become the three cords.
The posterior cord is formed from the three posterior divisions of the trunks (C5-T1 )
The lateral cord is the anterior divisions from the upper and middle trunks (C5-C7)
The medial cord is simply a continuation of the lower trunk (C8-T1)
In general, the lateral and medial cords supply the ventral aspect of the limb, whereas the posterior cord supplies the dorsal aspect

14. CORDS DIVISIONS TRUNKS ROOTS anterior C5 C6 posterior C7 C8 T1
LATERAL
UPPER C6
posterior
POSTERIOR
MIDDLE C7 C8
MEDIAL
LOWER T1

15. Branches
Finally, the cords give rise to various branches that supply the upper limb structures.
Some arise from the cervical part of the plexus
Most of the branches to the upper limb muscles arise from the plexus in the axilla
The terminal branches of the cords arise inferior to the clavicle

16. Cords Give off Branches!! (in axilla)
Lateral Musculocutaneous
Median
Medial Ulnar
Posterior Radial Axillary

17. The Musculocutaneous Nerve (C5-7)
Very variable, arises from the lateral cord.
It supplies the flexor muscles on the anterior aspect of the arm and the skin on the lateral side of the forearm

19. Injury to the Musculocutaneous Nerve
Injury to the musculocutaneous nerve in the axilla is uncommon because of its protected position
It is typically inflicted by a weapon
It results in paralysis of the coracobrachialis, biceps, and brachialis
Flexion of the elbow joint and supination of the forearm are greatly weakened
Loss of sensation may occur on the lateral surface of the forearm

20. The median nerve (C[5,] 6-8; T1)
The median nerve arises by lateral and medial heads from the lateral and medial cords,
The median nerve supplies most of the flexor muscles on the front of the forearm, most of the short muscles of the thumb
The median nerve supplies the skin on the lateral part of the front of the hand.
Articular branches to elbow, wrist, and carpal joints

22. Injuries to the Median Nerve
It is most commonly injured by stab wounds or broken glass just proximal to the flexor retinaculum at wrist

23. Injuries to the Median Nerve at the Elbow
Skin sensation is lost on
the lateral half or less of the palm of the hand and the palmar aspect of the lateral three and a half fingers.
the distal part of the dorsal surfaces of the lateral three and a half fingers.

24. The Hand of Benediction ( Pope’s Blessing )
No flexion is possible at the interphalangeal joints of the index and middle fingers,
When the patient tries to make a fist, the index and to a lesser extent the middle fingers tend to remain straight, whereas the ring and little fingers flex

25. The Ulnar Nerve (C7, 8; T1)
The ulnar nerve arises from the medial cord,
The ulnar nerve supplies:
Some of the flexor muscles of the anterior forearm
Many of the short muscles of the hand
The skin on the medial part of the palmar and dorsal aspect of the hand.

27. Injuries to the Ulnar Nerve
More than 27% of nerve lesions of the upper limb affect the ulnar nerve
Ulnar nerve injuries usually occur in four places:
Posterior to the medial epicondyle of the humerus
In the cubital tunnel
At the wrist.
In the hand.

28. Claw hand (main en griffe)
Ulnar nerve injury can result in extensive motor and sensory loss to the hand.
An injury to the nerve in the distal part of the forearm denervates most intrinsic hand muscles.
Difficulty making a fist because
The metacarpophalangeal joints become hyperextended,

29. Froment's sign
Froment's sign tests for palsy of the ulnar nerve, specifically, the action of adductor pollicis
If the patient is asked to grip a piece of paper between the thumb and the index finger
It is impossible to adduct the thumb because the adductor pollicis muscle is paralyzed.

31. The axillary nerve (C5, 6)
The axillary nerve is a branch of the posterior cord
The site of the axillary nerve may be represented by a horizontal line through the middle of the deltoid around the surgical neck .
It divides supplies the teres minor and deltoid and becomes the upper lateral brachial cutaneous nerve

32. Axillary Nerve

34. Axillary Nerve Injury
The axillary nerve is usually injured during fracture of the proximal end of the humerus
It may also be damaged during dislocation of the shoulder joint
Intramuscular injection of drugs in the deltoid muscle may injure the nerve
awareness of its location avoids injury to it during injections

35. Injury to the Axillary Nerve
Section of the axillary nerve results in:
The deltoid atrophies when the axillary nerve (C5 andC6) is severely damaged
Paralysis of the deltoid with incomplete abduction of the arm by the supraspinatus
Loss of sensation in a small patch of skin over the deltoid.

36. The Radial Nerve (C[5,] 6-8; [T1])
The radial nerve may be regarded as the continuation of the posterior cord.
It spirals around the posterior aspect of the humerus under cover of the lateral head of the triceps and thereby reaches the lateral aspect of the limb (hence the name radial).

37. The radial nerve supplies the extensor muscles of the posterior arm and forearm and the skin on the posterior arm, forearm, and hand.

38. The Radial Nerve Injury
The radial nerve may be injured in the axilla by pressure of a crutch or by hanging the arm over the back of a chair
" saturday night palsy"
Loss of sensation in areas of skin supplied by this nerve also occurs.

39. Injury to the Radial Nerve
The characteristic clinical sign of radial nerve injury is wrist-drop
inability to extend the wrist and the digits at the metacarpophalangeal joints

43. Erb’s palsy Injuries to superior parts of the brachial plexus (C5 and C6)
Usually result from an excessive increase in the angle between the neck and the shoulder
These injuries can occur in a person who is thrown from a motorcycle or a horse and lands on the shoulder in a way that widely separates the neck and shoulder
This stretches or tears (avulses) superior parts of the brachial plexus.
Injury to the superior trunk of the plexus is apparent by the characteristic position of the limb ("waiter's tip position")

44. Neonatal Brachial Plexus Palsy
It is due to over traction on the neck as in:
Shoulder dystocia.     
After-coming head in breech delivery.

45. The usual clinical appearance:
Upper limb with:
An adducted shoulder
Medially rotated arm
Extended elbow.
(policeman’s or waiter’s tip hand)
The lateral aspect of the upper limb also experiences loss of sensation

46. Klumpke’s palsy Injuries to inferior parts of the brachial plexus (C7 and C8 and 1st thoracic roots)
Injuries to inferior parts of the plexus are much less common.
Lower brachial plexus injuries may occur when the upper limb is suddenly pulled superiorly
When a person grasps something to break a fall
A baby's upper limb is pulled excessively during delivery

47. Klumpke’s palsy
This results in the sign known as clawed hand due to loss of function of the ulnar nerve and the intrinsic muscles of the hand it supplies.
Loss of sensation along the medial side of the arm.
If the 8th cervical nerve is damaged, the anesthesia will involve the medial side of the forearm, hand, and medial two fingers.

49. BLOOD SUPPLY TO UPPER LIMB
The arterial supply is mainly by;
Subclavian artery
Axillary artery
Brachial artery
Radial artery
Ulnar artery
Palmar arch
Digital arteries

50. Subclavian artery
It arise from bracheo- cephalic artery, pass behind clavicle bone over the first rib before entering the axilla where it continuous as axillary artery.
Before entering axilla each subclavian gives off two branches:
vertebral artery which supply to brain
internal thoracic artery which supply to breast and thoracic cavity.

51. Axillary artery continuation of subclavian artery and lies in axilla.
The first part lies deeply than it runs more superficial and becomes brachial artery.

52. Brachial artery
continuation of axillary artery
it runs down internal aspect of upper arm, passes to front of the elbow and extends to 1 cm below joint
devides radial and ulnar arteries.

53. Measuring Blood Pressure
Arterial blood pressure measurement using sphygmomanometer.
A cuff is placed around the arm and inflated with air until it compresses the brachial artery against the humerus and occludes it.
A stethoscope is placed over the artery in the cubital fossa, the pressure in the cuff is gradually released
The examiner detects the sound of blood beginning to spurt through the artery.
The first audible spurt indicates systolic blood pressure.
As the pressure is completely released, the point at which the pulse can no longer be heard is the diastolic blaod pressure.

54. Measuring Blood Pressure
Arterial blood pressure measurement using sphygmomanometer.
A cuff is placed around the arm and inflated with air until it compresses the brachial artery against the humerus and occludes it.
A stethoscope is placed over the artery in the cubital fossa, the pressure in the cuff is gradually released
The examiner detects the sound of blood beginning to spurt through the artery.
The first audible spurt indicates systolic blood pressure.
As the pressure is completely released, the point at which the pulse can no longer be heard is the diastolic blaod pressure.

55. Radial artery
passes down radial or lateral side of the forearm to the wrist.
Just above the wrist it lies superficially and can be felt in front of the radius, as the radial pulse.
The artery then passes between the first and second metacarpal bones and enters the palm of hand.

56. Ulnar artery
run down wards on the ulnar or inner aspect of forearm to cross wrist and pass into hand.

57. Palmar arch and Digital arteries
anastomoses between the radial and ulnar arteries, called as deep and superficial palmar arches, from which palmar metacarpal and digital arteries arise to supply the structures in the hand and fingers.

58. VENOUS RETURN FROM UPPER LIMB
The veins of upper limb divided into two groups; deep and superficial veins;
The deep veins follow the course of the arteries and have same names;
Palmar metacarpal vein
Deep palmar venous arch
Ulnar and radial veins
Brachial vein
Axillary vein
Subclavian vein

59. The superficial veins are;
Cephalic vein
Basilic vein
Median vein
Median cubital vein

60. Cephalic vein
begins back of the hand where it collects blood from superficial veins.
In front of the elbow it gives off a branch called as median cubital vein and joins basilic vein.

61. Basilic vein begins back of hand and joins axillary vein.
It recieves blood from inner aspect of hand, forearm and arm.
There are many small vein which links to cephalic and basilic vein.

62. Venipuncture of the Upper Limb
The median cubital vein is commonly used for venipuncture for:
Drawing blood
Inserting a catheter for right cardiac catheterization
The dorsal venous network and the cephalic and basilic veins arising from it are commonly used for intravenous feeding

63. Peripheral artery pulses in the upper limb

65. Lymphatic Drainage of the Upper Limb
Superficial lymphatic vessels
Arise from lymphatic plexuses in:
The digits
The palm
The dorsum of the hand
Ascend mostly with superficial veins
Deep lymphatic vessels:
Less numerous than superficial vessels
Accompany the major deep veins in the upper limb
Terminate in the humeral group of axillary nodes.

66. Lymphatic Drainage of the Upper Limb
Some vessels accompanying the basilic vein enter the cubital nodes, located:
proximal to the medial epicondyle
medial to the basilic vein.
Efferent vessels from these lymph nodes ascend in the arm and terminate in the humeral (lateral) axillary lymph nodes.
Most lymphatic vessels accompanying the cephalic vein cross the proximal part of the arm and anterior aspect of the shoulder to enter the apical group of axillary nodes; however, some vessels previously enter the deltopectoral nodes.