Spine Flashcards
What is the difference between syringomyelia and syringobulbia?
Syringomyelia is spinal cord; syringobulbia is brain stem.
What is the etiology of syringomyelia? (4)
- Cranocervical junction (Chiari malformities);
- spinal cord trauma;
- spinal cord tumors;
- post-infections
What are associated conditions with syringomyelia?
- congenital scoliosis (25-80%);
- Klippel-Feil;
- Charcot joints
What are the indications for an MRI with a patient with scoliosis? (5)
- abnormal curves - double apex (L);
- Neuro deficit/ABN reflexes;
- infantile/juvenile onset;
- Male;
- Kyphosis>30 degrees
Why do we need to identify a syrinx if there is a scoliosis?
Increased risk of neurological deficit if fusion is done with an undiagnosed syrinx.
What are the classifications of spinal cord tumors?
- Intradural - extramedullary;
- Intradural - intramedullary;
- Extradural
What is the most common intradural extramedullary tumor?
Schwannoma
What are the intradural extramedullary tumors?
- Schwannoma;
- Meningioma
Schwannoma is associated with which NF gene?
NF type II
What are 2 risk factors for spinal meningioma?
- NF II;
- Radiation
What is the Tx of spinal meningiona?
If Sx, complete Sx resection, Tx recurrence with radiation therapy
What are the 2 intramedullary intradural tumors?
- Astrocytoma;
- Ependymoma
What is the most common intradural intramedullary CNS tumor?
Ependymoma
How does one differentiate ependymoma from astrocytoma of CNS lesions?
- Astrocytoma - cerviothoracic, eosinophils on histology;
- Ependymoma - usually @ filium terminale, rosettes on hystology
What is the most concerning extradural tumor?
Lymphoma
What is the Tx of extradural lymphoma of the spine?
Chemo with methotrexate
What are 5 indicators of high energy trauma when considering C-spine injuries?
- > 35 mph MVA;
- > 10 feet;
- closed head injuries;
- neurodeficit referrable to C-spine;
- pelvis and extremity #s
What are 4 key history points for C-spine injuries?
- Ank. spond.;
- DISH;
- GLL/Marfans/ED;
- instrumentation/HW
What are 4 complications of late C-spine collar clearance?
- aspiration;
- resp function;
- decubitus ulcers;
- increased ICP
What is the immediate Tx of neurogenic shock?
- Swan-Ganz for fluid monitoring;
- pressors
What are 3 characteristics of spinal shock?
- flaccid paralysis;
- Bradycardia hypotension;
- absent Bulbocavernosis reflex
What are 5 contraindications to high dose methylprednisone?
- GSW;
- pregnancy;
- under 13 yoa;
- > 8 hours post injury;
- Bracial plexus injuries
What are the indications for decompression and stabilization for SCI GSW?
- progressive neurological deficit with retained bullet;
- cauda equina;
- retained bullet fragment within thecal sac (CSF can lead to lead poisoning)
What are the W/C functions of: 1. C3-C4; 2. C5; 3. C6; 4. C7
- C3-C4 - electric W/C with chin controls;
- C5 - electric W/C with hand controls;
- C6 - manual W/C with sliding board transfers;
- C7 - manual W/C with independent transfers
What is the most common incomplete cord injury?
Central cord
What are 4 key characteristics of central cord syndrome?
- motor deficit more to u/e than l/e;
- sacral sparing;
- good prognosis;
- often have permanent clumsy hands
What is the order of recovery for central cord syndrome?
- l/e first;
- bowel/bladder;
- prox u/e;
- distal u/e
What is the pathophys. of anterior cord syndrome?
- direct compression;
- anterior spinal artery injury
What are the key points for anterior cord syndrome?
- l/e more than u/e;
- loss LCT (motor), LST (pain, temp);
- preserved DC (vib, proprioception);
- worst prognosis of ISCI
What is the pathophys. of Brown-Sequard syndrome?
penetrating trauma
What are the physical findings in Brown-Sequard syndrome?
- ipsilateral - motor (LCST) - light touch, proprioception (DC);
- contralateral - pain, temp, light touch (LSTT)
What is the prognosis of Brown-Sequard syndrome?
Excellent - 99% ambulatory @ final followup
What are the key points of posterior cord syndrome?
- rare;
- Dorsal column affected;
- proprioception/vibration gone;
- motor/pain/light touch preserved
What is the most common cause of cauda equina syndrome?
disc protrusion (herniation)
What are 4 complications of cauda equina syndrome?
- sexual dysfunction;
- urinary dysfunction;
- chronic pain;
- persistent leg weakness
What is the most common complication of cervical laminoplasty?
C5
What nationality has a high frequency of isthmic spondylothesis?
Eskimo - > 50%
What 4 ligaments stabilize the occipitoatlantoaxial complex?
- transverse ligaments;
- paired alar ligaments;
- apical ligament;
- tectorial membrane
What is the Anderson and Montesano classification of the occipital condyle #s?
Type I - impact #, stable;
Type II - Basilar skull # with extension, stable;
Type III - avulsed alar ligament, can be unstable
What are the indications for operative management for OC #s?
- Type III with instability;
- neural compression;
- associated atlantoaxial or atlas injuries; Tx with OC - C2 or C3 fusion
What are the classifications of occipitocervical D/L?
Type I - anterior;
Type II - longitudinal;
Type III - posterior
What is Powers Ratio and its importance?
diagram: Powers Ratio = CD/AB; normal = 1;
1. > 1 concern for anterior D/L;
2. <1 post D/L, dens #, atlas #
What is a major contraindication to traction in cervical spine injuries?
OC D/L due to high (10%) rate of neurologic injury
Where is the thickest portion of the occiput?
5 cm lateral to the external occipital protuberance
What is the major complication associated with OC-cervical fusion?
Damage to major dural venous sinus located just inferior external occipital protuberance
Where do you place screws for OC fusion?
Safe zone located 2 cm lateral to EOP + 2 cm inferior to the EOP (Danger is dural venous plexus)
What are 9 causes of atlanto-axial instability?
- Down syndrome;
- RA;
- Os odontoideum;
- Type I odontoid #s;
- atlas #s;
- transverse ligament injury;
- JRA;
- Morquio’s;
- rotary atlanto-axial subluxation
What is the most important stabilizer of C1-C2 stability?
transverse ligament
What ADI is considered unstable in adults?
3.5 mm
What ADI is Sx indication in RA?
> 10 mm
What PADI or sac is indication for Sx in RA?
<14 mm
What sum of lateral mass overhang indicates transverse ligament disruption?
8.1 mm
What is C1 # classification?
Type I - isolated anterior/posterior arch #s;
Type II - Jefferson-Burst #, bilateral ant/post arch #s;
Type III - unilateral lateral mass #
What are 3 non-op indications for C1 #s?
- stable type I #s;
- stable type II #s - <3 m ADI or <8.1 displacement;
- stable type III #s <8.1 mm displacement
What are the indications for C1-C2 fusion or OC C2-C3 fusion in C1 #s?
- unstable type II #s;
- unstable type III #s;
- occipitocervical fusion if OC joint involved or poor purchase in C1
What are the options for fusing C1-C2?
- C1 lateral mass, C2 pars;
- C1 lateral mass, C2 pedicle;
- transarticular with Gallie/Brook/bone graft enhancement
What is the blood supply to Dens/C2?
- apex is carotid;
- base is vert.
What is the Andonson and D’Azunzo classification of C2 #s?
Type I - tip avulsion #s;
Type II - waist #s;
Type III -# extends into body
What are the radiographic parameters for atlanto-axial instability in OS odontoideum?
- need flex-ex films;
- ADI = > 10 mm;
- Sac or PADI < 13 mm
What is the Tx algorithm for C2 #/instability?
- OS odontoideum - observe;
- type I - cervical orthoses, 6-12 weeks;
- type II young - halo if RF (-), Sx if RF (+);
- type II old - collar if not Sx candidate, Sx if candidate;
- type III - hard cervical collar for 6-12 weeks
What are the indications for C2 osteosynthesis?
Type II C2 # with:
- acceptable alignment;
- # line perpendicular to screw trajectory;
- body habitus allows trajectory
What are the risk factors for C2 type II non-union? (5)
- > 5 mm displacement;
- # comminution;
- > 10 degrees angulation;
- age > 50;
- delay in Tx > 4 days
What is the order of ossification of the Dens?
Dens to base - about 6 yoa;
Tip to Dens - about 12 yoa;
Tip ossifies @ age 3
What is Levine and Edward’s classification of C2 Hangman’s #s?
- Type I - <3 mm displacement - not angulated;
- Type II - >3 mm displacement + angulated vertical # line;
- Type IIA - same as above but horizontal # line;
- Type III - Type I with B/L C2-C3 D/L
What is the Tx of type I Hangman’s #?
rigid cervical collar X 4-6/52
What is the Tx of type II Hangman’s #?
- If <5 mm - traction + halo;
- If >5 mm consider C1-C2 fusion
What is the Tx of type IIA Hangman’s #?
AVOID TRACTION due to horizontal # line;
Reduction + halo X 6-12/52 weeks
What is the Tx of type III Hangman’s #?
open reduction of facets with stabilization
What are the operative options for unstable Hangman’s #?
- Anterior C2-C3 interbody fusion;
- posterior C1-C3 fusion;
- B/L C2 pars osteosynthesis
How much displacement do UNI vs B/L facet dislocations lead to?
UNI - 25%;
B/L - 50%
What percentage of facet D/L will fail closed reduction?
26%
What lumbar Dx study leads to accelerated degenerative disc disease?
provocative discography
What is the congenital cause of spinal steiosis and why?
- Achondoplasta;
- due to short pedicles + medially based facets
What is Kemp sign?
a unilateral radiculopathy made worse by bending backwards
Vasc. vs Neuro claudication? (5)
Neuro IS + postural, standing stationary, going up stairs easier, stationary bike easier, pulses normal
What are the 7 steps of pedicle to pedicle decompression?
- remove spine proc.;
- remove lamina to LF;
- preserve PARS int.;
- decompress pedicle above;
- decompress pedicle below;
- decompress lateral recess;
- ensure no disc remnant
When to instrument with ped-to-ped decomp. for spinal stenosis? (3)
With segmental instability:
- spondy (isthmic);
- spondy (degen.);
- degen. scoliosis