ABOS Spine Flashcards
Where are sympathetic ganglia in cervical spine
C6 where middle cervical ganglia is, medial boarder of longus colli muscles
How is hypogastric plexus injuried
Anterior approach, retrograde ejaculation
Where do afferent nerve fibers arise
Medial branch nerves originating from next two cephalad levels; L3-4 facet joint innervated by L2 and L3 medial branches
Where does Artery of Adamkiewicz arise
left side b/w T8 and L1
What does neural tube become
from primative streak, becomes spinal cord (failure to closue anencephaly and spina bifida)
What does neural crest become
forms dorsal to neural tube
peripheral NS, pia mater, spinal ganglia, sympathetic trunk
What does notocord become
ventral to neural tube
vertebral bodies and intervertebral discs
NP from notocord, annulus from sclerotomal cells (resegmentation)
Smallest and largest pedicles
T4 smallest, L1 smallest in lumbar spine
T12 largest
What is concerning change in signals for SEPS and MEP
50% amplitude or 10% increase in latency
What is EMG concerning for breached pedicles
<8mA
What nerve can be injured with anterior cervical exposure up to C2
hypoglossal
Landmarks for anterior approach
Angle of mandible C1-C2
Hyoid bone C3-4
Thyroid cartilage C4-5
Cartoid tubercle C6
Anterolateral approach to thoracic spine
2 levels caudal for vertebral body exposed
Segmental arteries at risk midbody b/w intervertebral disks
Diaphragm can be taken down, medial risk of phrenic nerve
Lumbar plexus runs through posterior 2/3rd
Where is superior hypogastric plexus
on L5 body - retrograde ejaculation
A diagram of the back of a human body
Anterior approach to spine
transperitoneal, retroperitoneal
ureters, round ligament, iliac vessels, hypogastric plexus
sympathetic trunk medial to border of psoas, lateral to psoas is ilioinguinal nerve and farther lateral is GFN
Anterior cord syndrome findings
lower extremities more affected than upper, loss of motor and p&T
Flexion/compression injuries
Worst prognosis of all incomplete SCI
Brown-Sequard syndrome
hemitransection, excellent prognosis, 99% ambulatory at final follow up
Central cord syndrome
hyperextension injury in elderly
upper extremity and hands
Good prognosis if <50
Lower extremity recovers first, then bowel/bladder, upper then hands
typically regain ability to walk, hand may remain spastic
surgical decompression only if persistent cord compression
When to decompress for incomplete spinal cord injury
decompress when hit neurologic plateau or worsen, may recover 1-2 levels
Function level depending on cord injry level
C4- puffer, C5 hand controls, C6 manual wheel chair, C7 manual wheel chair with independent transfers
Causes of occipitocervical instability
Traumatic
Acquired: Downs, bony dysplasia, soft-tissue laxity, RA, Mucco
Requires instability of alar, tectorial membrane and alanto-occipital joint capsules
How to diagnosis occipitocervical instability
CT scan occipital condyle-C1 interval <1.5mm
Occipital condyle fracture
cervical orthosis, sugery only if neuro deficits
Powers ratio
Basion to posterior arch/anterior arch to opisthion
1 normal; >1 or <1 concern for anterior or posterior dislocation