anatomy of brachial plexus

1. ANATOMY OF
BRACHIAL PLEXUS
Submitted to -Dr. Manoj malik
Submitted by-Ankush
Roll no. 15172001
MPT 1st year

2. Brachial plexus
• The brachial plexus is an arrangement of nerve
fibres formed by intercommunications among the
ventral rami of the lower four cervical nerves
( C 5 - C 8) and the first thoracic nerve (T 1).
• The plexus is responsible for the motor
innervation to all of the muscles of the upper
limb and the sensory innervation of the upper
limb.

3. Spinal Nerve

4. FORMATION OF THE BRACHIAL
PLEXUS
• Roots
– The ventral rami of spinal nerves C5 to T1 are referred to as the roots of
the plexus.
• Trunks
– Shortly after emerging from the intervertebral foramina , these 5 roots
unite to form three trunks.
– The ventral rami of C5 & C6 unite to form the Upper Trunk.
– The ventral ramus of C 7 continues as the Middle Trunk.
– The ventral rami of C 8 & T 1 unite to form the Lower Trunk.
• Divisions
– Each trunk splits into an anterior division and a posterior division.
– The anterior divisions usually supply flexor muscles
– The posterior divisions usually supply extensor muscles

5. Diagrammatic representation of the
Brachial Plexus

6. Branches

7. RELATIONS
• In the neck, the brachial plexus lies in the
posterior triangle, being covered by the skin,
Platysma , and deep fascia; where it is crossed by
the supraclavicular nerves, the inferior belly of
the Omohyoideus , the external jugular vein, and
the transverse cervical artery.
• When It emerges between the Scaleni anterior
and medius; its upper part lies above the third
part of the subclavian artery, while the trunk
formed by the union of the eighth cervical and
first thoracic is placed behind the artery.

8. • the plexus next passes behind the clavicle, the
Subclavius, and the transverse scapular vessels,
and lies upon the first digitation of the Serratus
anterior, and the Subscapularis.
• In the axilla it is placed lateral to the first
portion of the axillary artery; it surrounds the
second part of the artery, one cord lying medial to
it, one lateral to it, and one behind it; at the lower
part of the axilla it gives off its terminal branches
to the upper limb.

9. Distribution of the branches of
the brachial plexus
Axillary nerve (C5-C6): gives an articular branch
to the shoulder joint, motor innervation to the
deltoid and teres minor muscles and sensory
innervation to part of deltoid and scapular
regions.

10. • Radial nerve (C5-C6-C7-C8): It provides motor
innervation to the triceps, anconeus, part of
the brachialis, brachioradialis, extensor carpi
radialis and all the ex tensor muscles of the
posterior compartment of the forearm. Its
injury produces a characteristic “wrist drop”.

12. Median nerve (C5-C6-C7-C8-T1): In the forearm
it provides motor innervation to the anterior
compartment except the flexor carpi ulnaris and
the medial half of the flexor digitorum
profundus (ulnar nerve). In the hand provides
motor innervation to the thenar eminence and
the first two lumbricals.

14. Ulnar nerve (C8-T1): Its motor component
supplies the flexor carpi ulnaris and the medial
half of the flexor digitorum profundus. In the
hand it provides the motor supply to all the
small muscles of the hand except the thenar em
inence and first two lumbricals (median).

17. Thank you