Brachial Plexus

Front 1

BRACHIAL PLEXUS:
-Nerves (5):

Back 1

C6-T2

Front 2

THORACIC LIMB:
-Main Arteries (4):

Back 2

-Subclavian a.
-Axillary a.
-Brachial a.
-Median a.

Front 3

SUBCLAVIAN A.:
-Branches (2):

Back 3

-Superficial Cervical a.
-Axillary a.

Front 4

SUPERFICIAL CERVICAL A.:
-Supplies (4):

Back 4

-Muscles of the:
-Neck
-Scapula
-Shoulder
-Superficial Cervical Lnn.

Front 5

AXILLARY A.:
-Branches (5):

Back 5

-Subscapular a.
-Brachial a.
-Other small branches:
-External Thoracic a.
-Lateral Thoracic a.
-Cranial Circumflex a.

Front 6

EXTERNAL & LATERAL THORACIC AA.:
-Origin:
-Supply (5):

Back 6

-Cutaneous trunci m.
-Axillary a.
-Latissimus dorsi m.
-Superficial pectoral m.
-Deep pectoral m.
-Thoracic mammae

Front 7

CRANIAL CIRCUMFLEX HUMERAL A.:
-Origin:
-Supplies (2):

Back 7

-Axillary a.
-Biceps brachii m.
-Shoulder Joint Capsule

Front 8

SUBSCAPULAR A.:
-Origin:
-Branches (2):

Back 8

-Axillary a.
-Caudal Circumflex Humeral a.
-Thoracodorsal a.

Front 9

THORACODORSAL A.:
-Origin:
-Supplies (3):

Back 9

-Subscapular a.
-Teres major m.
-Latissimus dorsi m.
-Skin

Front 10

CAUDAL CIRCUMFLEX HUMERAL A.:
-Origin:
-Supplies (5):

Back 10

-Subscapular a.
-Triceps brachii mm.
-Deltoideus mm.
-Coracobrachialis m.
-Infraspinatus m.
-Shoulder Joint Capsule

Front 11

BRACHIAL A.:
-Branches (5):

Back 11

-Collateral Ulnar a.
-Common Interosseous a.
-Median a.
-Small Branches:
-Superficial Brachial a.
-Transverse Cubital a.

Front 12

COLLATERAL ULNAR A.:
-Origin:
-Supplies (3):

Back 12

-Brachial a.
-Triceps brachii m.
-Ulnar n.
-Elbow

Front 13

COMMON INTEROSSEOUS A.:
-Origin:
-Branches (3):
-Supplies (4):

Back 13

-Brachial a.
-Ulnar a.
-Cranial&Caudal Interosseous aa.
-Deep digital flexor m.
-Flexor carpi ulnaris m.
-Palmar surface of manus
-Craniolateral Antebrachial mm

Front 14

SUPERFICIAL BRACHIAL & TRANSVERSE CUBITAL AA.:
-Origin:
-Supply (3):

Back 14

-Brachial a.
-Dorsum of Manus
-Elbow
-Associated mm.

Front 15

MEDIAN A.:
-Branches (3):

Back 15

-Superficial Palmar Arch
-Radial a.
-Deep Antebrachial a.

Front 16

DEEP ANTEBRACHIAL A.:
-Origin:
-Supplies (4):

Back 16

-Median a.
-Flexor carpi radialis m.
-Superficial digital flexor m.
-Deep digital flexor m.
-Flexor carpi ulnaris m.

Front 17

THORACIC LIMB:
-Main Nerves (9):

Back 17

-Suprascapular n.
-Subscapular n.
-Musculocutaneous n.
-Axillary n.
-Thoracodorsal n.
-Radial n.
-Median n.
-Ulnar n.
-Lateral Thoracic n.

Front 18

SUPRASCAPULAR N.:
-Origin (2):
-Course:
-Innervates (2):

Back 18

-C6&C7
-Runs btw. Supraspinatus & Subscapularis mm. near neck of scapula
-Supraspinatus m
-Infraspinatus m.

Front 19

SUBSCAPULAR N.:
-Origin (2):
-Innervates (1):

Back 19

-C6&C7
-Subscapularis m.

Front 20

MUSCULOCUTANOUS N.:
-Origin (3):
-Course:
-Branches (1):
-Innervates:

Back 20

-C6, C7, C8
-Runs btw. biceps brachii m. Cranially and Brachial vessels Caudally (deep to insertion of biceps brachii m.)
-Branch connects with Median n.
-Cranial mm. of Brachium (elbow joint flexors) and sensory to medial antebrachium skin
-Coracobrachialis m.
-Biceps brachii m.
-Brachialis m.

Front 21

AXILLARY N.:
-Origin (2):
-Course:
-Branches (1):
-Innervates:

Back 21

-C6, C7
-Runs btw. subscapularis & teres major mm. at level of neck of scapula
-Br. sensory to skin on Lateral brachium & Caudal Scapula
-Flexors of shoulder joint:
-Subscapularis m.
-Teres major&minor mm.
-Deltoideus m.

Front 22

THORACODORSAL N.:
-Origin (1):
-Course:
-Innervates (1):

Back 22

-C8
-Runs w/ thoracodorsal vessels on medial surface of muscle
-Latissimus dorsi m.

Front 23

RADIAL N.:
-Origin (4):
-Course:
-Branches (2):
-Innervates:

Back 23

-C7, C8, T1, T2
-Runs distally for a short distance with trunk of median/ulnar nn., enters triceps brachii m. distal to teres major m., wraps around humerus on caudal & lateral surface of Brachialis m., terminates as deep & superficial brs. on lateral side of distal third of brachium
-Caudal mm. of Brachium (extensors of elbow):
-Triceps brachii m.
- Tensor fasciae antebrachii m.
-Anconeous m.

Front 24

RADIAL N.:
DEEP BRANCH:
-Innervates (6):

Back 24

-Extensors of Carpal&Digital Joints(Craniolateral Antebrachial mm.):
-Extensor carpi radialis m.
-Common digital extensor m.
-Lateral digital extensor m.
-Ulnaris lateralis m.
-Abductor pollicus longus m.
-Supinator m.

Front 25

RADIAL N.:
SUPERFICIAL BRANCH:
-Branches (3):
-Innervates (2):

Back 25

-Dorsal Common Digital nn.
-Craniolateral Skin of Forearm
-Dorsal Surface of Manus

Front 26

MEDIAN N.:
-Origin (3):
-Course:
-Innervates:

Back 26

-C8, T1, T2
-Cranial division=Runs along caudal surface of Brachial a. proximally & Median a. distally deep to pronator teres m., flexor carpi radialis m. & humeral head of ddf m., passes into carpal canal
-sensory to palmar surface of manus
-Flexors of Carpal&Digital Joints (Caudomedial Antebrachial mm.):
-Flexor carpi radialis m.
-Superficial&Deep digital
flexor mm.
-Pronator teres&quad. mm.

Front 27

ULNAR N.:
-Origin (3):
-Course:
-Branches (1):
-Innervates (3):

Back 27

-C8, T1, T2
-Caudal Division=crosses elbow caudal to medial epicondyle of humerus
-sensory to skin of caudal antebrachium
-Flexors of carpal & digital Joints:
-Flexor carpi ulnaris m.
-Deep digital flexor m.
-5th Digit

Front 28

LATERAL THORACIC N.:
-Origin (3):
-Course:
-Innervates (1):

Back 28

-C8, T1, T2
-Runs caudally btw latissimus dorsi & deep pectoral mm, passes adjacent to axillary ln
-Cutaneous trunci m.

Front 29

C6:
-Branches (4):

Back 29

-Suprascapular n.
-Subscapular n.
-Musculocutaneous n.
-Axillary n.

Front 30

C7:
-Branches (5):

Back 30

-Suprascapular n.
-Subscapular n.
-Musculocutaneous n.
-Axillary n.
-Radial n.

Front 31

C8:
-Branches (6):

Back 31

-Musculocutaneous n.
-Thoracodorsal n.
-Radial n.
-Median&Ulnar nn.
-Lateral Thoracic n.

Front 32

T1&T2:
-Branches (4):

Back 32

-Radial n.
-Median&Ulnar nn.
-Lateral Thoracic n.

Front 33

Major Arteries, Veins, & Nerves of the Manus (6):

Back 33

-Dorsal Common Digitals
-Axial Dorsal Proper Digitals
-Abaxial Dorsal Proper Digitals
-Palmar Common Digitals
-Axial Palmar Proper Digitals
-Abaxial Palmar Proper Digitals

Front 34

Dorsal surface of manus main branches:
-Artery:
-Vein:
-Nerve:

Back 34

-Cr. Superficial Brachial a. (branch from Brachial a.)
-Accessory cephalic v.
-Radial(digits I-III) & Ulnar (digit V) nn. (digit IV has overlap)

Front 35

Palmar Surface of Manus main branches:
-Artery:
-Vein:
-Nerve:

Back 35

-Median a.
-Cephalic v.
-Median & Ulnar nn. (overlap)

Front 36

Which 2 nerves have a common trunk?

Back 36

Median&Ulnar nn.

Front 37

MEDIAN & ULNAR NN.
-Origin:
-Course:
-Innervate:

Back 37

-C8, T1, T2
-Common trunk along Medial head of Triceps brachii m. btw Brachial v. Caudally & Brachial a. Cranially
-Caudomedial Antebrachial mm. (flexors of carpal & digital joints)

Front 38

Describe the types of axons found in nerves of brachial plexus?

Back 38

-All contain somatic EFFERENT neurons to striated muscles and Afferent neurons from muscles.
-Some have Cutaneous Somatic Afferents

Front 39

Which nerves of the brachial plexus have Cutaneous Somatic Afferent Axons?

Back 39

-Musculocutaneous n.
-Axillary n.
-Radial n.
-Median & Ulnar nn.

Front 40

Which nerve is subject to injury due to exernal compressive forces as it runs across the Scapular notch?

Back 40

Suprascapular n.

Front 41

What would you see if the entire brachial plexus was cut?

Back 41

-Animal unable to bear weight on limb
-presents the same as if radial n. alone was damaged
-to diagnose, test autonomous zones of radial, ulnar, and musculocutaneous nerves

Front 42

RADIAL N.
-Autonomous zone:

Back 42

-Cranial lateral surface of antebrachium
-dorsal surface of manus (digits I, II, III)

Front 43

ULNAR N.
-Autonomous zone:

Back 43

-Caudal surface of antebrachium
-Dorsal/Lateral Surface of 5th digit

Front 44

MUSCULOCUTANEOUS N.
-Autonomous zone:

Back 44

-Medial surface of antebrachium

Front 45

Regarding autonomous zone, what is special about palmar surface of manus?

Back 45

There is no autonomous zone b/c of overlap of cutaneous zones of Ulnar&Median nn. (Median n. has no autonomous zone)