Brachial plexus .pdf

Brachial plexus

Contents :
Location
General features
Roots
Trunks
Divisions
Cords

Branches
--> Branches from roots
--> Branches from trunks
--> Branches from lateral cord
--> Branches from Medial cord
--> Branches from Posterior cord

Applied Anatomy
--> ERB's palsy
--> klumpke's palsy
--> Injury to nerve to sarretus anterior

1. BRACHIAL PLEXUS
-YASH ANGHAN

2. LOCATION
•It starts from cervical
spinal roots then runs
downwars.
•it passes laterally over
the first rib and enters
in the axilla to supply
the upper limb.

3. GENERAL FEATURES
•Brachial Plexus is only a group of Nerves which supplies whole
Upper Limb.
•The brachial plexus is composed by 5 anatomical components: 5
roots, 3 trunks, 6 divisions, 3 cords, and 5 terminal branches

4. ROOTS (5)
•Five roots include the anterior
branches of the 4 lowest cervical
spinal nerve roots (C5-C8) and the
first thoracic nerve root (T1). Rarely,
it is co-contributed by C4 and T2
•The origin of the plexus may shift by
one segment eitherupward or
downward, resulting in a prefixed or
postfixed plexus respectively.

5. TRUNKS (3)
•As it have 3 trunks which are conjoint
from that 5 roots as follows.
•Roots C5 and C6 join to form the
upper trunk.
•Root C7 formsthe middle trunk.
•Roots C8and T1 join to forthelower
trunk.

6. DIVISIONS (6)
•Each trunk (three in number)
divides into ventral andorsal
divisions (which ultimately supply
the anteriorand posterior aspects
of the limb). These divisions
Further joint toform cords.

7. CORDS
Now those division further joints and made cords
i. The lateral cord is formed by the union of ventral
divisions of the upper and middle trunks (twodivisions).
ii. The medial cord is formed by the ventral divisionof
the lower trunk (one division).
iii. The posterior cord is formed by union of the dorsal
divisions of all the three trunks (three divisions).

8. BRANCHES
Brachial plexus gives many of branches and these branches can be branches from
different parts and according to that branches can be studies as follows.
•Branches from Root.
•Branches from Trunks
•Branches from Cords
i) from lateral cord
Ii) from midile cord
iii) from posterior cord

9. BRANCHES
FROM ROOTS
1. Nerve to serratus anterior
(long thoracic nerve) (C5,
C6, C7)
2. Nerve to rhomboids
(dorsal scapular nerve) (C5).
BRANCHES FROM
TRUNKS
These arise only from the upper
trunk which gives twobranches.
1. Suprascapular nerve (C5, C6)
2 Nerve to subclavius (C5, C6)

10. BRANCHES FROM LATERAL CORD
1 Lateral pectoral (C5-C7)
2 Musculocutaneous (C5-C7)
3 Lateral root of median (C7-C7)

11. BRANCHES FROM MEDIAL CORD
•1 Medial pectoral (C8, T1)
•2 Medial cutaneous nerve of arm (C8, T1)
•3 Medial cutaneous nerve of forearm (C8, T1)
•4 Ulnar (C7, C8, T1). C7 fibres reach by a communicating branch from
lateral root of median nerve.
•5 Medial root of median (C8, T1)

12. BRANCHES FROM POSTERIOR CORD
•1 Upper subscapular (C5, C6)
•2 Nerve to latissimus dorsi (thoracodorsal) (C6, C7,C8)
•3 Lower subscapular (C5, C6)
•4 Axillary (circumflex) (C5, C6)
•5 Radial (C5-C8, T1)

13. APPLIED ANATOMY
•There are numerous applieds belongs to
brachial plexus but hear we will see about
only 3 applieds
1.ERB’S PALSY
2.KLUMPKLE’S PALSY
3.INJURY TO N. TO SERRATUS ANTERIOR

14. ERB’S PALSY
Site of injury. One region of the
uppertrunkof thebrachialplexus
is called Erb’s point . Sixnerves
meet here. Injury to the upper
trunk causesErb's paralysis.

15. -Cnuses of injury: Undue separation of the head from the shoulder, which
is commonly encountered in the following.
i. Birth injury
ii. Fall on the shoulder
iii. During anaesthesia.
-Nerverootsinvolved; Mainly C5 and partly C6.
-Musclesparalysed: Mainly biceps brachii, deltoid,
brachialis and brachioradialis. Partly supraspinatus,
infraspinatus and supinator.

16. -Deformity and position of the limb
Arm: side; it is adducted and mediallyrotated.
Forearm: Extended and pronated
-Disability
The following movements are lost.
o Abductionand lateral rotation of the arm atshoulder joint.
o Flexion and supination of the forearm, Biceps and supinator jerks are lost.
o Sensations are lost over a small area over thelower part of the deltoid.

17. KLUMPKE’S PALSY
•Site of injury: Lower trunk of the brachial
plexus
•Cause of injury:
•Undue abduction of the arm, as in clutching
something with the hands after a fall from a
height, or sometimes in birth injury.
•Nerve roots involved; Mainly T1 and partly
C8.

18. •Muscles paralyse
o Intrinsic muscles of the hand (T1).
o Ulnar flexors of the wrist and fingers (C8).
•Deformity and position of hand.
•Claw hand due to the unopposedaction of the long
flexors and extensoroff the fingers. In a claw hand
there is hyperextension at the
metacarpophalangeal joints and flexion at the
interphalangeall joints.
•Disability: Completeclaw-hand (Fig. a.U).
Cutaneous anaesthesia and analgesia in a narrow
zonealong the ulnar border of the forearm and
hand.

19. INJURY TO SARRETUS ANTERIOR
•Causes
•1 Suddenpressure on the shoulder from above.
•2 Carrying heavy loads on the shoulder.
•Deformity: Winging of the scapula, i.e. Excessive prominence of
the medial border of the scapulaNormallyy, the pull of the muscle
keeps the medial borderagainst the thoracic wall.
•Disability
Loss of pushing and punching actions. During attempts atpushing,
there occurs winging of the scapula
Armcannot be raised beyond 90 i.e. Overheadabduction is not
possible as it is performed by thserratus anteriormuscle.

20. Thank you