anatomy midterm Flashcards
what nerve does a lateral lumbar disc protrusion affect?
normally affects the nerve root below
ex. protrusion at L4/5 affects L5 nerve root
what nerve does a medial lumbar disc protrusion affect?
medial protrusion at L4/5 rarely affects L4 nerve root but may affect L5 nerve root and S1-4 nerve roots
etiology of a herniation of nucleus pulposus
extreme/sudden hyper-flexion of vertebral column
repeated strain or compression of vertebral column
can be idiopathic or asymptomatic
characteristics of HNP
most common location is lumbar spine
esp L4/5 IVC
symptoms of HNP
pain in the lower back, radiating to one or both LE
what is the most typical spinal level if IVD herniation?
in lumbar spine because WB is the highest
L4/5 or L5/S1 are most common
what vertebral level is best for lumbar puncture?
L4/5 or L5/S1
ensures that conus medullaris and cauda equina are missed
borders of the suboccipital triangle
superomedial: rectus capitis posterior major
superolateral: obliquus capitis superior
inferolateral: obliquus capitis inferior
floor: posterior AO membrane, posterior arch of C1
roof: semispinalis capitis
contents of the suboccipital triangle
vertebral artery
suboccipital nerve
suboccipital venous plexus
borders of the quadrangular space
superior - teres minor
inferior - teres major
medial - long head of the triceps brachii
lateral - surgical neck of the humerus
innervation of serratus anterior muscle
long thoracic nerve (C3,4,5)
action of serratus anterior
protraction
upward rotation
stabilization of scapula
what does damage to the long thoracic nerve do?
weaken serratus anterior
what causes winging of the scapula?
complete severing of the long thoracic nerve
inactivation of SA inhibits scapula from being held into the thoracic wall
what 4 muscles perform internal rotation of GH?
a lesion of suprascapular nerve would likely result in what motor deficits?
what are the contents of the carpal tunnel
flexor digitorum profundus tendons
flexor digitorum superficialis tendons
flexor pollicis longus tendon
median nerve
boundaries of carpal tunnel
posterior/floor - carpal bones
anterior/roof - flexor retinaculum
what is carpal tunnel syndrome?
synovial sheaths become inflamed with overuse, expanding against the other structures in the tunnel
axillary nerve sensory innervation
upper half of upper arm
radial nerve sensory innveration
lower lateral half of upper arm and most of posterior arm
musculocutaneous nerve sensory innervation
lateral side of anterior forearm and lateral posterior forearm
median nerve sensory innervation
anterior lateral hand and digits 1-lateral half of 4 and posterior tips of digits 1-4
ulnar nerve sensory innervation
medial hand and medial half of digit 4 and digit 5
division 1 of axillary artery
1 rib is landmark for transition from subclavian to axillary
branch: superior thoracic a.
division 2 of axillary artery
deep to pectoralis minor
branches: thoracoacromial a., lateral thoracic a.
division 3 of axillary artery
inferior to pec minor and anterior to teres major
branches: subscapular a. (circumflex scapular a. and thoracodorsal a.), posterior humeral circumflex a., anterior humeral circumflex a.
what four muscles make the anterior abdominal wall?
rectus abdominis
external abdominal oblique
internal abdominal oblique
transversus abdominis
what does an abdominal hernia occur?
when an organ pushes through a weakness in abdo wall muscle or CT
groin is another common place
common sites of abdominal hernias
umbilicus
incisional
hiatal
what is the treatment of a hernia?
surgical repair
small ones can be monitored, but will get worse over time
where is the ansa cervicalis nerve?
loop sitting anterior to scalene
hypoglossal CN XII
inferior to mandible
phrenic nerve location
C3-5 to the diaphragm
where does the vagus nerve run?
medially to common carotid artery
boundaries of the anatomical snuffbox
extensor pollicis longus
extensor pollicis brevis
abductor pollicis longus
floor of the snuffbox
scaphoid
trapezium
contents of the snuffbox
radial artery
superficial radial nerve
cephalic vein
what is nurse maid’s elbow?
head of radius displaced from annular lig
what causes nurse maid’s elbow?
common in children following pulling movement
swinging by hands
how to correct nursemaid’s elbow?
elbow and wrist held with forearm in 90 deg flexion
forearm rapidly hyperpronated
radial head should click back into place
upper roots injury (C5,C6): Erb-Duchenne’s paralysis
excessive increase in angle between head and shoulder
paralysis of shoulder and arm muscles supplied by C5 and C6
Erb-duchenne palsy - waiter’s tip: arm add and hangs by side in medial rotation
what deficits are associated with erb-duchenne’s palsy?
loss of abd - delt
loss of IR - infra, T minor
weak forearm flexors - biceps, brachialis
weak supination - biceps
square shoulder due to delt atrophy
lower roots injury (C7, C8, T1): Klumpke’s paralysis
sudden stop when upper limb raised over head
intrinsic muscles of hand deficits
claw hand
what deficits are associated with claw hand?
loss of thenar and hypothenar innervation
loss of lumbricals and interossei
hyperextension of MCP joints
loss of extension of IPs
axillary nerve lesion (C5, C6)
humeral surgical neck fracture
improper use of crutches
posterior dislocation of GH
square shoulder sign
what deficits are associated with square shoulder sign?
severe weakness of shoulder abd
weakness in lateral rotation of shoulder
lesions to suprascapular nerve
loss of supra and infra
weak abd and LR
lesions to upper and lower subscapular nerve
loss of subscap and t major
weak add and MR
lesions to long thoracic
loss of serr ant
winged scap
lesions to pectoral nerve
weak pec major/minor
weak MR, add
lesions to thoracodorsal nerve
loss of lats
weak arm ext, add, MR
lesions to dorsal scapular
loss of rhomboids
weak scap retraction
injury to spinal accessory nerve
most common surgery related nerve injury
paralysis of trap
signs:
shoulder drop
cannot shrug against resistance
musculocutaneous nerve lesion C5-7
rare to injure only musculo
stab or puncture
similar to upper brachial plexus injury
severe weakness of elbow flexion and supination
median nerve lesion C5-T1
deep perforating wounds, cuts at wrist, carpal tunnel
median nerve lesion proximal to elbow
loss of pronation
weak wrist flexion and abd
loss of IP flexion and 2-3
weak Ip flexion in 4-5
impaired thumb
sign of benediction
1-3 remain extended when trying to make a fist
forearm supination
wrist ulnar deviated
median nerve lesion at wrist
loss of intrinsic thumb muscles
ape hand:
wasting thenar
thumb slightly extended
ulnar nerve lesion C8-T1
gunshot wound, fracture of med epi
ulnar nerve lesion proximal to elbow
weak wrist flex and add
loss of flex in dip of 4-5
loss of flexion of mcp of 4-5
loss of extension of ip of 4-5
loss of abd and add of digits
loss of thumb add
loss of digit 5 abd and flex
partial claw hand
deficits with partial claw hand
flexion of PIP of 4-5
hyperextension of 4-5 mcp
impaired wrist add, hand in radial deviation
ulnar nerve lesion at wrist
exaggerated partial claw hand
same as partial claw hand but additional flexion in dip
radial nerve lesion - axilla (C5-T1)
compression due to crutches
loss of forearm ext
weak forearm flexion
weak supination
wrist drop
deficits with wrist drop
wrist in flexe position
radial nerve lesion in spiral/radial groove
fracture to humeral shaft
wrist drop
radial nerve lesion in cubital fossa
laceration
wrist ex weakened
loss of mcp ext
loss of thumb ext
weak supination
difficulty holding pen and writing
