Download MBBS (Bachelor of Medicine, Bachelor of Surgery) Human Anatomy ppt lectures Topic 85 Brachial Plexus Notes. - anatomy ppt free download human anatomy ppt lectures, medicine notes ppt, anatomy handwritten notes pdf, mbbs 1st year anatomy notes pdf download, best anatomy notes pdf, human anatomy notes pdf, anatomy easy notes pdf, anatomy notes online, anatomy short notes, Anatomy ppt, Powerpoint Presentations and lecture notes.
Learning objectives
? Formation of brachial plexus
? Components ? roots, trunks, divisions &
branches
? Relations ? cervical & axillary part
? Main nerves of arm, forearm & hand
? Nerve course, injuries & applied aspects
Wasted Thenar Muscles
Winging of scapula
Winging of
scapula
Wrist drop
Week 7
Week 5
RULE -
Limbs are outgrowths of ventral
body wall that undergo distal
growth and dif erentiation...5th
Week
and rotation...7th week
Upper Limb
Anterior
Muscle
Compartments
Humerus
Arm
Posterior
Anterior
Forearm
Radius
Ulnar
Posterior
Anterior
Hand
5th metacarpal
Anterior
Humerus
Arm
Posterior
Few muscles of posterior
compartment are present in
anterolateral aspect of
Anterior
forearm (*brachioradialis,
supinator)
Forearm
*
Radius
Ulnar
Posterior
Anterior
Hand
No posterior compartment in the hand
5th metacarpal
Anterior
Musculocutaneous n.
Motor innervation
Muscle Compartments
Humerus
Radial n.
Posterior
Anterior
Median n. & Ulnar n.
Radius
Ulna
Radial n.
Posterior
Ulnar n. & Median n.
Anterior
5th metacarpal
Posterior
Muscles of Arm: Cross elbow Move forearm
? Two compartments ? Anterior & posterior
? 1. Anterior: Flexors of forearm
? 2. Posterior: Extensors of forearm
Anterior Compartment ? MCN + Axillary A & Brachial A
? Biceps brachii = Musculocutaneous nerve
? Brachialis = Musculocutaneous nerve
? Coracobrachialis = Musculocutaneous nerve
? Brachioradialis = Radial nerve
Posterior Compartment ? RN + Profunda Brachii Artery
? Triceps brachii = Radial nerve
? Anconeus = Radial nerve
RULE : Ventral vs. dorsal limb mm.
Developmentally-dorsal muscles:
? Lie posterior to the long bones in anatomical position
(* exceptions)
Developmentally-ventral muscles:
? Lie anterior to the long bones in anatomical position
*
Brachial plexus
? Supraclavicular part ? neck ? posterior
triangle b/w sclaneus anterior & sclaneus
medius ? roots & trunks
? Infraclavicular part ? axilla ? divisions /cords
& branches
? Cords ? named as per relation to second part
of axillary artery ? deep to pectoral minor
? Lateral cord ? lateral , posterior cord ?
posterior & medial cord ?medial to 2nd part
of axillary artery
Brachial Plexus
(right side; simplified)
"Roots of BP"
(=ventral rami)
C5
C6
Trunks
C7
U
Divisions
C8
M
Cord
Terminal
Lat
L
T1
Branches
Post
Med
Anterior (ventral) division
Posterior (dorsal) division
Brachial Plexus
(right side; simplified)
"Roots of BP"
(=ventral rami)
C5
C6
Trunks
C7
U
Divisions
C8
M
Cord
Terminal
Lat
L
T1
Branches
Post
Musculocutaneous n.
Med
Median n.
Radial n.
Anterior (ventral) division
Ulnar n.
Posterior (dorsal) division
Brachial plexus - cords
Lateral cord ? LML ? Lateral Pectoral n, Musculocutaneous
n, lateral root of Median n
Medial cord ? MMMMU ? Medial pectoral n, Medial
cutaneous n of forearm, Medial cutaneous n of arm , Ulnar
n & Medial root of median n.
Posterior cord ? LUNAR ? Lower subscapular n, Upper
subscapular n , Nerve to latissimus dorsi, Axillary n & Radial
n.
31
Brachial plexus - cords
1. Lateral cord ? LML ? Lateral Pectoral n,
Musculocutaneous n, lateral root of Median n
2. Medial cord ? MMMMU ? Medial pectoral n,
Medial cutaneous n of forearm, Medial
cutaneous n of arm , Ulnar n & Medial root of
median n.
3. Posterior cord ? LUNAR ? Lower subscapular n,
Upper subscapular n , Nerve to latissimus dorsi,
Axillary n & Radial n.
32
Brachial plexus - cords
1. Lateral cord ? LML ? Lateral Pectoral n,
Musculocutaneous n, lateral root of Median n
2. Medial cord ? MMMMU ? Medial pectoral n, Medial
cutaneous n of forearm, Medial cutaneous n of arm ,
Ulnar n & Medial root of median n.
3. Posterior cord ? LUNAR ? Lower subscapular n, Upper
subscapular n , Nerve to latissimus dorsi, Axillary n &
Radial n.
33
Brachial plexus ? supraclavicular
branches - roots & trunks
? Branch to Phrenic nerve ?C5 ?anterior to sclaneus
anterior
? Dorsal scapular n ? C5 ? pierces sclaneus medius,
supplies rhomboids & levator scapulae
? Long thoracic n ? C5C6C7 ? (C7 ? may be absent) upper
two roots C5C6 pierce sclaneus medius , runs b/w
sclaneus ant & medius ? Supply - serratus anterior.
? TRUNKS ? Upper
? Nerve to subclavius ? Erb's Point - C5 C6 ?subclavius (
gives - accessory phrenic nerve ?C5)
? Suprascapular n- C5C6 ? supra & infraspinatus , articular
? shoulder, acromioclavicular,
34
Brachial plexus-
? Lateral pectoral n- C5C6C7 ? LC -larger, pierces
clavipectoral fascia ,ant to axillary art- pectoralis major
& minor.
? Medial pectoral n- C8T1-MC- , pierces pectoralis minor
& supplies both pectoralis major & minor.
? Upper sub scapular n- smaller ? frequently double.
? Lower sub scapular n- subscapularis & teres major.
? Axillary n- ant branch ?deltoid & post branch- has
pseudoganglion supplies teres minor ,cutaneous ? as-
upper lateral cutaneous nerve of arm .
Brachial Plexus
C5
(branches)
C6
supraspinatus
suprascapular n.
C7
& infraspinatus
*
mm.
C8
T1
**
upper subscapular n.
subscapularis m.
axillary n. thoracodorsal n.
latissimus dorsi
lower subscapular n.
m.
deltoid & teres minor mm.
Brachial Plexus
(branches)
rhomboid mm.
dorsal
scapular n.
C5
C6
suprascapular n.
C7
*
C8
pectoralis mm. lateral pectoral n.
serratus
T1 anterior m.
musculoskeletal
n.
long
thoracic n.
medial n.
medial pectoral n.
pectoralis
**
mm.
upper subscapular n.
thoracodorsal n.
axillary n.
lower subscapular n.
ulnar n.
radial n.
Brachial Plexus
(all branches)
Dorsal
scapular n.
C5
C6
Suprascapular n.
C7
*
C8
Lateral pectoral n.
T1
Musculoskeletal n.
Long
thoracic n.
Medial n.
Medial pectoral n.
**
Upper & lower subscapular nn.
Thoracodorsal n.
Axillary n.
Ulnar n.
* Nerve to subclavius
Radial n.
** Medial brachial & antebrachial cutaneous nn.
Brachial plexus - cords
Lateral cord ? LML ? Lateral Pectoral n, Musculocutaneous
n, lateral root of Median n
Medial cord ? MMMMU ? Medial pectoral n, Medial
cutaneous n of forearm, Medial cutaneous n of arm , Ulnar
n & Medial root of median n.
Posterior cord ? LUNAR ? Lower subscapular n, Upper
subscapular n , Nerve to latissimus dorsi, Axillary n & Radial
n.
39
Brachial plexus - cords
? Lateral cord ? LML ? Lateral Pectoral n,
Musculocutaneous n, lateral root of Median n
? Medial cord ? MMMMU ? Medial pectoral n, Medial
cutaneous n of forearm, Medial cutaneous n of arm ,
Ulnar n & Medial root of median n.
? Posterior cord ? LUNAR ? Lower subscapular n, Upper
subscapular n , Nerve to latissimus dorsi, Axillary n &
Radial n.
Nerve supply of Scapular Muscles
? Origin on Scapula:
? Latissimus dorsi = Thoracodorsal nerve /N to
latissimus dorsi
? Subscapularis & Teres Major = Subscapular nerves
? Supraspinatus & Infraspinatus = Suprascapular
nerves
? Deltoid & Teres Minor = Axillary nerve
? Insertion on Scapula
? Levator Scapularis & Rhomboids = Dorsal Scapular
nerve
? Pectoralis Minor = lat & medial Pectoral nn.
? Serratus anterior = Long Thoracic n/nerve of bell
? Trapezius = Accessory spinal n.
Branches - Posterior Cord
? Axillary Nerve ( w . Circumflex vs..)
? Supplies:
? Deltoid & Teres minor (motor supply )
? Capsule of shoulder
? skin of lower part covering deltoid (sensory
supply)
? Subscapular Nerves {C5,C6} : Subscapularis &
Teres major
? Thoracodorsal Nerve : Latissimus dorsi
Injury to axillary nerve
Waisting of shoulder
Winging of the Scapula
Combined Axillary and Long Thoracic Nerve
Injuries
Fore arm ?muscles
1. Flexor Compartment : Anterior
(Superficial 5 + Deep 3) - supplied by
Median, Anterior Interosseous Nerve &
Ulnar nerves
2. Extensor Compartment : Posterior
(Superficial + Deep)
Radial & Posterior interosseous nerve.
Radial nerve injury in arm
Wrist drop
Anterior Compartment Forearm = 5 +3
1 Pronator teres
Median n
2 Flexor digitorum superficialis Median n
3 Flexor carpi radialis
Median n
4 Palmaris longus
Median n
5 Flexor carpi ulnaris
Ulnar nerve
1 Pronator quadratus
Anterior interosseous n-Median n
2 Flexor digitorum profundus
Anterior interosseous n-Median n
& Ulnar nerve
3 Flexor pollicis longus
Anterior interosseous n- Median n
Posterior Compartment Forearm ?
superficial - 7
1 Anconeus
Radial n
2 Brachioradialis
Radial n
3 Extensor carpi radialis longus
Radial
4 Extensor carpi radialis brevis
Posterior interosseous? Radial n
5 Extensor digitorum
Posterior interosseous? Radial n
6 Extensor digiti minimi
Posterior interosseous? Radial n
7 Extensor carpi ulnaris
Posterior interosseous? Radial n
Posterior Compartment Forearm ? deep - 5
1 Supinator
Posterior interosseous? Radial n
2 Abductor pollicis longus
Posterior interosseous? Radial n
3 Extensor pollicis brevis
Posterior interosseous? Radial n
4 Extensor pollicis longus
Posterior interosseous? Radial n
5 Extensor indicis
Posterior interosseous? Radial n
Hand ? Median nerve - 5
Flexor pollicis brevis
Median n
Abductor pollicis brevis
Median n
Opponens pollicis
Median n
1st lumbrical
Median n
2nd lumbrical
Median n
Hand ? Ulnar nerve - 15
Flexor digiti minimi
Ulnar n
Abductor digiti minimi
Ulnar n
Opponens digiti minimi
Ulnar n
Interossei ? palmar & dorsal (8) Ulnar n
3rd & 4th lumbricals (2)
Ulnar n
Palmaris brevis
Ulnar n ? superficial branch
Posterior Compartment of Forearm
Muscle
Nerve
? Superficial
? Extensor carpi radialis Longus & Brevis
RN
? Extensor digitorum (communis) RN
? Extensor digiti minimi
RN
? Extensor carpi ulnaris
RN
? Deep (post gp) - PIN
? Supinator
Radial n + PIN
? Abductor pollicis longus
PIN
? Extensor pollicis longus + brevis PIN
? Extensor indicis
PIN
An inability to oppose thumb to little finger
can result from injury to -
a) Axillary n
b) Radial n
c) Ulnar n
d) Median n
Hyperextension of proximal phalanges of
little and ring fingers can happen due to
nerve injury of -
a) Ulnar
b) Axillary
c) Radial
d) Median
Inablity to abduction of arm can happen due
to nerve injury of -
a) Axillary
b) Musculocutaneous
c) Radial
d) Median
Wrist drop can result from damage to -
a) Median n
b) Ulnar n
c) Radial n
d) Anterior interosseous n
This post was last modified on 05 April 2022