Anatomy Brachial Plexus videos + notes
thoracodorsal n supplies
latissimus dorsi
what innervates the serratus anterior
long thoracic n
innervation of subscapular
lower subscapular
innervation of teres major
lower subscapular
what innervates teres majo
lower subscapular
what innevates the lower part of the subscapularis and teres major
lower subscapular
musculocutaneous n is motor to - sensory to -
m - anterior flexors of arm s - arm and lateral forearm
what does medial brachial innervate
medal brachial skin
what cord does the ulnar nerve come from
medial
what supplies pectoralis major
medial AND lateral pectoral nn.
what are the preterminal branches of the medial cord
medial brachial, medial antebrachial cutaneous, medial pectoral
what are the branches of the medial cord
medial cutaneous brachial medial cutaneous antebrachial medial pectoral ulnar
what supplies pectoralis minor
medial pectoral
what nerve innervates the radial 2 lumbricals
median
what nerve innervates the skin of the palmar aspect of the radial 3.5 digits
median
what nerve innervates the skin of the thumb side of the palm
median
sensory innervation - median vs ulnar
median: lateral 3.5 fingers, palmar surface, superiodorsal aspect of fingers (fingertips) ulnar: dorsal and palmar aspect of medial 1.5 fingers, just below fingertips
the musculocutaneous nerve innervates (m and s)
muscles of anterior arm skin of lateral aspect of arm
the lateral cord gives off the lateral root of the median nerve and then continues as the - n.
musculocutaneous
branches of the brachial plexus and the cords they originate from
musculocutaneous from lateral cord median nerve from lateral and medial cords axillary and radial nn. from posterior cord ulnar nerve from medial cord "MARMU"
what nerve is likely injured if the patient cant flex elbow
musculocutaneous n
what cord does the axillary nerve come from
posterior
what cord does the radial nerve come from
posterior
the - cord terminates by dividing into the axillary and radial nerves
posterior cord
where does the lower subscapular nerve originate
posterior cord
where does the thoracodorsal nerve originate
posterior cord
where does the upper subscapular nerve originate
posterior cord
the posterior cord is formed by what division(s)
posterior divisions of all trunks (superior, middle, inferior)
where do the preterminal branches of the posterior cord innervate
posterior muscles of the axilla (upper and lower subscapular, thoracodorsal)
where does the suprascapular nerve originate supplies:
superior trunk supraspinatus, infraspinatus mm.
the axillary and radial nerves contain fibers from which trunks
superior, middle and inferior - contains the posterior divisions of all of them.
what innervates supraspinatus and infraspinatus
suprascapular n
what innervates latissimus dorsi
thoracodorsal
what nerve innervates all of the interossei
ulnar
what nerve innervates flexor carpi ulnaris
ulnar
what nerve innervates the adductor pollicis
ulnar
what nerve innervates the deep head of the flexor pollicis brevis
ulnar
what nerve innervates the ulnar half of the flexor digitorum profundus
ulnar
if - nerve is injured, the thumb CAN still flex/oppose, but the fingers can't be abducted or adducted
ulnar n
the medial cord gives off the medial root of the median nerve and then continues as the -
ulnar n.
subscapularis is innervated by
upper and lower subscapular
what are the preterminal branches of the posterior cord
upper and lower subscapular, thoracodorsal
what innervates the upperpart of the subscapularis muscle
upper subscapular n.
what are the branches of the posterior cord
upper subscapular, thoracodorsal, lower subscapular terminates as axillary and radial
what emerge from the scalene interval
ventral rami and trunks of the plexus, subclavian artery
what spinal nerves innervate the triceps and extensors of the wrist and fingers
C7 (6,8)
- dermatome = ulnar 2 digits, medial aspect of hand and wrist
C8
what spinal nerves innervate the thumb muscles
C8
what spinal nerves are responsible for flexion of wrist and fingers
C8 (7, T1)
what cord does the musculocutaneous nerve come from
lateral
the median nerve is given off by what cords
lateral and medial
the anterior divisions of the trunks form - cords
lateral and medial cords
where does the lateral pectoral nerve originate
lateral cord
what cords give off the median nerve
lateral cord gives lateral root, medial cord gives off medial root
what is the only preterminal branch of the lateral cord
lateral pectoral n.
- dermatome = middle finger, middle of hand
C7
- dermatome = shoulder pad area
C4
- dermatome = lateral aspect of arm and elbow
C5
what spinal nerves provide innervation to deltoid and other intrinsic muscles of the shoulder
C5, 6
what spinal nerves are responsible for elbow flexion and supination of forearm
C5,6
what spinal nerves provide innervation to biceps, brachialis, and supinator
C5,6
what spinal nerves are responsible for shoulder abduction, hyperextension, and external rotation
C5,6 (intrinsic muscles of shoulder, deltoid)
- dermatome = lateral aspect of forearm and hand, radial 2 digits
C6
what spinal nerves innervate the pronators (internal rotators) of the forearm
C6,7,(8)
- dermatome = medial aspect of forearm, elbow, lower arm
T1
what spinal nerves are responsible for finger adduction/abduction
T1
what spinal nerves innervate the little finger muscles and interossei
T1
- dermatome = medial aspect of upper arm
T2
the musculocutaneous, median, and ulnar nerves arise from anterior/posterior divisions of the trunks
anterior (flexors)
course of musculocutaneous n
anterior arm, exits lateral forearm
the medial cord is formed by what division(s)
anterior division of the inferior cord
the - will innervate the anterior or flexor muscles, while the - will innervate the posterior or extensor muscles of the upper limb
anterior divisions posterior divisions
course of median nerve
anterior to elbow, between heads of pronator teres
what nerve supplies teres minor
axillary
what nerve supplies the deltoid
axillary
what nerve supplies the skin over the insertion of the deltoid
axillary
scalene interval =
between anterior and middle scalene mm, first rib
median vs ulnar claw hand
distal median n. injury: loss of 2 lateral lumbricals, patient asked to open fist, but 2nd and 3rd stay flexed proximal median: patient tries to punch, ends up "blessing"; loss of thumb opposition, lateral lumbricals stay flexed ulnar: loss of medial lumbricals, can't extend 4th or 5th digits, can't abduct or adduct fingers
innervation of levator scapulae
dorsal scapular
innervation of rhomboids
dorsal scapular
what innervates the rhomboids and levator scapulae
dorsal scapular
median nerve is motor to
forearm: lateral flexors except FCU (ulnar n.) hand: lateral 2 lumbricals, thenar eminence via recurrent branch
what nerve innervates the radial 3.5 digits proximal to the IP joints
radial
what nerve supplies the skin of the lateral 2/3 of hand
radial
where does the phrenic nerve originate
root of C3,4,5
what is the root of the dorsal scapular n? dorsal scapular n. innervates:
root of C5 supplies levator scapulae, rhomboids
where does the long thoracic nerve originate
roots of C5,6,7
explain the roots, trunks, divisions, and cords of the brachial plexus
roots: spinal nerves C5-T1 trunks: superior = C5,C6, middle = C7, inferior = C8,T1 divisions: anterior division of superior trunk continues as lateral cord; anterior division of inferior trunk continues as medial cord; the posterior divisions of all 3 superior, middle, inferior trunks come together and form the posterior cord cords: superior trunk becomes the lateral cord, middle trunk becomes the posterior cord, inferior trunk becomes medial cord
what does antebrachial cutaneous innervate
skin of anterior forearm
what does the lower subscapular supply
subscapular and teres major
upper subscapular n supplies
subscapularis m
the anterior divisions of the - and - trunks join to become the lateral cord
superior and middle