Brachial Plexus Flashcards
What do the anterior rami of spinal nerves C5-T1 form?
the Brachial Plexus
Describe how the brachial plexus weaves in and out of the clavicle and 1st rib
It is posterior to the clavicle, but anterior to the first rib
How many roots are there in the brachial plexus?
5 (C5-T1)
Where do these roots pass through?
The gap between the anterior and middle scalene muscles along with the subclavian artery
In the inferior part of the neck the 5 roots unite to form what?
3 trunks
What are the names of the 3 roots and how did they form?
Superior Trunk formed from the union of C5 and C6
Middle Trunk is just a continuation of C7
Inferior Trunk formed from the union of C8 and T1
What happens to the three roots as they pass posterior to the clavicle?
They divide into anterior and posterior DIVISIONS
These divisions form what?
3 CORDS
Lateral, Medial, and Posterior
The lateral cord forms as a result of what?
The union of the anterior division of superior and middle trunks
The medial cord forms as a result of what?
It is just a continuation of the anterior division of the inferior trunk
The posterior cord forms as a result of what?
The union of the posterior divisions of all 3 trunks
Each cord gives rise to what?
Branches or Nerves
How many branches arise from the lateral cord?
What are they called?
3
1) Lateral Pectoral Nerve
2) Musculocutaneous Nerve
3) Median Nerve (partly)
How many branches arise from the medial cord?
What are they called?
5
1) Median Pectoral Nerve
2) Medial Brachial Cutaneous Nerve
3) Medial Antebrachial Cutaneous Nerve
4) Median Nerve (partly)
5) Ulnar Nerve
How many branches arise from the posterior cord?
What are they called?
5
1) Upper Subscapular Nerve
2) Lower Subscapular Nerve
3) Thoracodorsal Nerve
4) Axillary Nerve
5) Radial Nerve
There are 2 branches/nerves that arise from the roots, what are they?
1) Dorsal Scapular Nerve
2) Long Thoracic Nerve
There are 2 branches/nerves that arise from the trunks, what are they?
1) Nerve to Subclavius
2) Suprascapular Nerve
The Long thoracic nerve has origins from where?
C5-7
What does the long thoracic nerve innervate?
Serratus Anterior
The dorsal scapular nerve has origins from where?
C5
What does the dorsal scapular nerve innervate?
Rhomboids
Levator Scapulae
The subclavian nerve has origins from where?
C5 and C6
What does the subclavian nerve innervate?
Subclavius
The suprascapular nerve has origins from where?
C5 and C6
What does the suprascapular nerve innervate?
Supraspinatous
Infraspinatous
The lateral pectoral nerve has origins from where?
C5 and C6
What does the lateral pectoral nerve innervate?
Pectoralis Major
The upper subscapular nerve has origins from where?
C5 and C6
What does the upper subscapular nerve innervate?
Superior Portion of Subscapularis
The thoracodorsal nerve has origins from where?
C6-8
What does the thoracodorsal nerve innervate?
Latissimus Dorsi
The lower subscapular nerve has origins from where?
C5-6
What does the lower subscapular nerve innervate?
Inferior Portion of Subscapularis
Teres Major
The medial pectoral nerve has origins from where?
C8 and T1
What does the medial pectoral nerve innervate?
Pectoralis Major and Minor
The medial brachial cutaneous nerve has origins from where?
T1
What does the medial brachial cutaneous nerve innervate?
Skin of medial side of arm
The medial antebrachial cutaneous nerve has origins from where?
C8 and T1
What does the medial antebrachial cutaneous nerve innervate?
Skin of medial side of forearm
The musculocutaneous nerve has origins from where?
C5-7
What does the musculocutaneous nerve innervate?
Corocobrachialis
Brachialis
Biceps Brachii
The axillary nerve has origins from where?
C5 and C6
What does the axillary nerve innervate?
Deltoid
Teres Minor
The radial nerve has origins from where?
C5-T1
What does the radial nerve innervate?
Triceps Brachii Anconeus Bracioradialis Supinator Extensors of the Forearm
The median nerve has origins from where?
C5-T1
What does the median nerve innervate?
Pronator Teres Flexor Carpi Radialis Palmaris Longus Flexor Digitorum Superficialis Flexor Digitorum Profundus (lateral half) Flexor Pollicus Longus Pronator Quadratus Lumbricals 1 & 2 Opponens Pollicis Abductor Pollicis Brevis Flexor Pollicis Brevis
The ulnar nerve has origins from where?
C7-T1
What does the ulnar nerve innervate?
Flexor Carpi Ulnaris
Flexor Digitorum Profundus (ulnar half)
Intrinsic Hand Muscles
