The brachial plexus is formed by the anterior rami of cervical spinal nerves C5-T1. It has roots, trunks, divisions, cords, and terminal branches that provide motor and sensory innervation to the upper limb. Injuries can cause conditions like Erb's palsy or Klumpke's paralysis. The brachial plexus can also be blocked for anesthesia of the upper extremity.

1. BRACHIAL
PLEXUS
PROF RUCHIRA SETHI
UNS ASMC JAUNPUR, UP

2. LEARNING OBJECTIVES
• To learn about location and formation of brachial plexus
• To discuss the components of brachial plexus
• To discuss about Erb’s point & palsy
• To learn about the deformity produced in Klumpke’s paralysis
• To discuss various other clinical aspects of the plexus

3. Structure of a Typical Spinal Nerve

4. Scalene group of muscles
Scalenus anterior
Scalenus medius
Scalenus posterior
Innervated by cervical
spinal nerves

5. Formation:
anterior primary rami of
C5,C6,C7,C8 & T1 spinal nerve,
in the neck.
• Pre-fixed plexus –C4
• Post –fixed plexus—T2

6. Components: Roots C5,C6,C7,C8,T1 Located in neck behind
scalenus anterior
Trunks Upper trunk
Middle trunk
Lower trunk
Located in lower part neck
between cleft of s.anterior
& medius
Divisions Anterior division(3)
Posterior division (3)
Located behind clavicle
Cords Lateral cord
Medial cord
Posterior cord
Located under clavicle,
posterior to subclavian
artery
Terminal branches Musculocutaneous
Axillary Ulnar
Median Radial
In arm , forearm & hand
Innervation Cutaneous innervation &
motor supply to complete
upper limb

7. Relations of Brachial Plexus
• Trunks lie in neck; lower trunk posterior to
artery while upper and middle behind the
subclavian artery
• Divisions enter axilla through cervico-
axillary canal
• Cords & branches form the infraclavicular
part of plexus
• Cords are in relation to axillary artery

8. Relations of axillary artery
First part axillary artery
Second part axillary artery

9. Third part axillary artery

11. Branches of Roots:
1. Nerve to serratus anterior or long thoracic nerve of Bell (C5-C7)
2. Nerve to rhomboideus major & minor (dorsal scapular nerve) (C5)
3. Branches to longus colli & scalene group of muscles (C5-C8)
4. Phrenic nerve (C5)

12. Branches from trunks
From Upper trunk
Suprascapular nerve- for supraspinatus & infraspinatus
Nerve to subclavius- for subclavius
Erb’s point

13. Branches from Cords
From Lateral cord
1. Lateral pectoral nerve
2. Musculocutaneous n
3. Lateral root of median nerve
From Posterior cord
1. Lower subscapular nerve
2. Upper subscapular nerve
3. Nerve to latissimus dorsi
4. Axillary nerve
5. Radial nerve
From Medial cord
1. Medial pectoral nerve
2. Medial cutaneous nerve of arm
3. Medial cutaneous nerve of forearm
4. Ulnar nerve
5. Medial root of median nerve

14. Applied Aspects of Brachial Plexus
1. Erb’s paralysis (injury to upper brachial plexus)
2. Klumpke’s paralysis (injury to lower brachial plexus)
3. Horner’s syndrome
4. Brachial plexus nerve block

15. Cutaneous innervation
of the upper limb

18. Erb’s Paralysis
1. At Erb’s point
2. Excessive increase
between head & shoulder
3. Policemen tip hand
4. Shoulder adducted and
medially rotated
5. Elbow extended
6. Forearm pronated

20. Klumpke’s Paralysis
1. Lower trunk injury
2. Upward traction (forced abduction)
3. Involves C8,T1
4. Characteristic Claw hand
5. Fingers hyperextendedat MCP joint & flexed at IP joint
6. Adduction & abduction of fingers is lost
7. Sensory loss over medial side of arm forearm and hand

23. Horner’s syndrome
If T1 is injured proximal
to white rami
communicantes to first
thoracic sympathetic
ganglion

26. Brachial Plexus Block
• Blockade of the brachial plexus is an effective method for providing anesthesia to the
upper limb from the shoulder to the fingertips
• Interscalene brachial plexus block: anesthesia to the from the distal extent of the
clavicle, shoulder joint, and proximal humerus
• Superior trunk block: provides analgesia to the shoulder capsule and proximal humerus.
diaphragm sparing modification of the interscalene block.
• Supraclavicular brachial plexus block: anesthesia of the upper limb from the mid
humerus to the fingertips.
• Infraclavicular brachial plexus block: anesthesia of the upper limb from the mid-
humerus to the fingertips. This block typically spares the intercostobrachial nerve.
• Axillary brachial plexus block: anesthesia of the upper limb from mid humerus to the
fingertips. This block also spares the intercostobrachial nerve,