Spine Flashcards
1
Q
What are 4 types of vertebrae seen in the pediatric c-spine?
A
- Oval- immature
- Reounded upper corner
- Anterior wedging
- Rectangular - mature
2
Q
How many pairs of cervical nerve roots are there?
Thoracic? Lumbar? Sacral? Coccygeal?
Total?
A
- Cervical - 8
- Thoracic - 12
- Lumbar- 5
- Sacral -5
- Coccygeal - 1
- Total- 31
3
Q
At what level does the Cauda Equina start?
A
L1
4
Q
What is the function of the rubrospinal tract? Crossed or uncrossed?
A
- Involuntary control, flexors and extensors (posture)
- Works with corticospinal tract
- Crossed
5
Q
What is the function of the Ventral Spinocerebellar Tract? Crossed or uncrossed?
A
- Unconscious muscle sense
- Crossed
6
Q
Describe Central Cord Syndrome
A
- Most common incomplete spinal cord lesion
- Upper extremity weaker than lower extremity (hands have more pronounced deficits than arms)
- Upper extremity has LMN signs
- Lower extremity has UMN signs
- Sacral sparring
- Prognosis good
7
Q
Describe Brown Sequard Syndrome
A
- Complete cord hemitransection
- Ipsilateral Defects
- LCS - motor function, spastic paralysis
- Dorsal Column - proprioception & vibration
- Contralateral Defects
- LST - pain & temp
- Spinothalamic tract crosses 2 levels below
- LST - pain & temp
- Best prognosis, 99% ambulate
8
Q
What is the function of the lateral corticospinal tract. Crossed or uncrossed?
A
- Voluntary control of skeletal muscles
- Crossed
9
Q
What is the function of the ventral corticospinal tract? Crossed or uncrossed?
A
- Voluntary control skeletal muscles
- Uncrossed (Crosses at level of termination)
10
Q
What is the function of the Dorsal Column? Crossed or uncrossed?
A
- Fasiculus gracile and cuneate
- Proprioception & vibration sense
- Crossed
11
Q
What is the function of the Dorsal Spinocerebellar Tract? Crossed or uncrossed?
A
- Muscle Sense
- Uncrossed
12
Q
What is the function of the Lateral Spinothalamic Tract? Crossed or uncrossed?
A
- Pain & Temperature. Light Touch
- Crossed
13
Q
Describe Anterior Cord Syndrome.
A
- Motor and sensory deficit below level of SCI
- Lower extremity > upper extremity
- Loss of LCT - motor, LST - pain & temp
- Preserved dorsal column - proprioception and vibration
- Worst prognosis
14
Q
Where does the spinothalamic tract cross?
A
Two levels below site.
15
Q
ASIA Spinal Cord Injury Scale
A
- A - Complete motor and sensory
- B- Sensory preserved, no motor
- C- >50% muscles, <3/5 below level
- D - >50% muscles, >3/5 below level
- E- Full motor and sensory
B-D are incomplete. Sacral sparring.
16
Q
What is the bulbocavernosus reflex, how do you preform it, and what does it represent?
A
- Yank on a foley in both men and women and look for an anal wink (present)
- If bulbocavernosus reflex is absent, patient is in spinal shock
- Cannot declare ASIA level when patient is in spinal shock
17
Q
What is the mechnaism of autonomic dysreflexia?
A
- Spinal Cord Injury - T6 or above
- Hypertension bleow the level of injury dues to nerves detecting painful stimumi
- Reaches T5-T6 where splanchnic sympathetic chain perpetuates sympathetic response
- Baroreceptors in Aortic Arch and Carotid sinus sense these changes, stimultes PNS
-
VAGUS NERVE - stimulates bradycardia and vasodilation above the level of injury
- This does not signal down the cord due to the spinal cord injury
-
Result: bradycardia and hypotension above the lesion, and perpetual hypertension below the lesion
- Only way to stop is to remove the painful stimuli
18
Q
Where do you find the exiting nerve root at:
The level of the Pedicle?
Level of the Body?
Level of the Disc?
A
Where do you find the exiting nerve root at:
The level of the Pedicle? - Central
Level of the Body? - Lateral Recess
Level of the Disc? - Foramen
19
Q
Causes of Spinal Stenosis
A
- Facet Hypertrophy
- Thickened Ligamentum Flavum
- Herniated Discs
- Osteophytes
- Spondylolisthesis
20
Q
What are the levels of the “3 Storey House”?
A
- Top Floor: Pedicles (TP, bottom, part of facet)
- Middle Floor: Foramen (top part facet). Supeiror facet can migrate up and impinge foramen
- Ground Floor: Disc (bulk of facet)
- Majority of the stenosis happens here
21
Q
Where is the descending nerve root at the Pedicle?
Body?
Disc?
A
Pedicle - Central
Body - Central
Disc - Central
22
Q
What is normal thoracic kyphosis?
A
10-40 degrees
23
Q
What is normal Lumbar Lordosis?
A
Thoracic Kyphosis + 30 degrees
24
Q
What is normal Cervical Lordosis?
A
20-40 degrees
25
What is the Spinal Vertical Axis (SVA), and what does it help determine?
* Plum line from centre of C7
* Determines sagitall balance
* Normal crosses superior corner of S1 body +/- 2.5cm
* Behind = increased lordosis
* Infront = hip flexion contracture
26
What is Pelvic Tilt and it's normal value?
* Angle between:
* Vertical line through centreof femoral head
* Line from centre of fremoal head to centre of S1 endplate
* Normal = 13 +/- 12 degrees
27
When doing sagital deformity correction of the lumbar spine, what degree of correction do you aim for?
Aim to correct lumbar lordosis within 10 degrees of pelvic incidence
28
What is the placement zone for 8mm occipital screws?
+/- 2cm at the nuchal line
+/- 1cm, 1cm below the nuchal line
+/- 0.5cm, 2cm below the nuchal line
29
What screw length do you use for occipital screws?
8mm
30
What are the contraindications to transarticular C1 C2 screws?
1. Medial, "high-riding" vertebral artery (20% of patients)
2. Subluxation C1 on C2
3. Cervothoracic kyphosis
31
What percentage of people have a high-riding vertebral artery?
20%
32
What is pelvic incidence?
* Angle between:
* Line perpendicular to S1 endplate
* Line from centre of S1 endplate to centre of femoral head
* Fixed in each individulal
* **Pelvic Incidence = Pelvic Tilt + Sacral Slope**
* **Normal 54 +/-20**
33
What is sacral slope? Normal values?
* Angle between:
* Horizontal line
* Line along superior endplate of S1
* Normal 41 +/- 16 degrees
34
Describe different vertebral osteotomies for correction of sagital alignment. (2)
1. Ponte Osteotomy (aka Smith Peterson)
* Remove inferior articular process of superior vertebrae and superior articular facet of inferior vertebrae
* Resect ligamentum flavum
* 10 degree correction per osteotomy level
2. Pedicle Subracting Osteotomy
* Posteiror resection of facet, portions of the laminae and pedicles
* Correction:
* 35 degrees per level lumbar spine
* 25 degrees per level thoracic spine
35
What are fixation options for C1? (3)
1. Transarticular
2. Lateral Mass Screws
3. Clamping/Wiring
36
What are fixation options for C2? (5)
1. Transarticular
2. Clamping/Wiring
3. Pars Screws
4. Pedicle Screws
5. Laminar Screws
37
Which cervical vertebrae have a vertebral foramen? Though which does the vertebral artery run?
All of them have foramen.
Vertebral artery runs through C1-C6
38
What is the contraindication to C1C2 fixation with wiring?
Cannot wire if you don't have intact posterior elements (trauma, tumour, decompression)
39
What is immediately behind fixation zones for occipital screws?
Dural venous sinuses
40
What is the difference between Neurogenic Shock and Spinal Shock?
1. Neurogenic Shock - cardiovascular shock resulting in bradycardia and hypotension
2. Spinal Shock is shock to the spinal cord itself secondary to trauma. Results in decrease motor/sensation and lack of bulbocavernosus reflex.
41
What is the orientation of the cervical facets?
45 degrees in sagittal, 0 degrees in axial
42
What is the orientation of the thoracic facets?
60 degree sagittal, 20 degrees frontal
43
What is the orientation of the lumbar facets?
90 degrees sagittal, 45 degrees on axial
44
What is the start point for lumbar pedicle screws?
* Vertically along superior facet
* Hortizontally inersect the TP
45
What structure is at risk with C1-C2 lateral mass screws?
Internal Carotid A.
46
What are 2 techniques for insertion of lateral mass screws?
1. Roy-Camille Technique
* Entry point in middle of lateral mass
* Aim 10 degrees lateral, and 0 degree in vertical plane
2. Magerl Technique
* Entrypoint slightly medial and superior to middle of lateral mass
* 25 degrees in lateral, 45 degrees in vertical plane
47
Where is the occiput thickest?
5cm lateral to the occipital protuberence
48
Which thoracic verterbrae has the smallest pedicle? Lumbar?
* Thoracic - T4
* Lumbar - L1
49
What is the start point for thoracic pedicle screws?
* Verticle - middle of facet
* Horizontal - superior ridge of TP or inferior base of facet joint
50
In the setting of bilateral C5C6 facet dislocation, which of the following anatomic structures is ususally preserved?
1. Facet joint capsule
2. Ligamentum Flavum
3. Posterior Annulus
4. Anerior longitudinal ligament
5. Interspinous ligament
4. Anerior longitudinal ligament
51
What are the dangers when inserting lateral mass screws?
1. Spinal Nerve Roots
2. Spinal Cord
3. Vertebral Artery
52
What structure is directly anterior in trajectory for Roy-Camille technique of lateral mass screw insertion?
Nerve Root
53
What is the principle blood supply to the lower 2/3 of the spinal cord? Where is it found?
* Artery of Adamciewicz aka artery radicularis magna
* Between T7-L4
* Most comonly left T10
54
Where do spinal arteries recieve blood from in the cervical spine?
1. Vertebral Arteries
2. Posterior Inferior Cerebellar Artery (PICA)
3. Segmental Branches
55
In what percentage of peopel is the A. of Adamciewicz found on the right side?
25%
56
Where does the nerve root exit in the C-Spine? T/L Spine?
* C-Spine: exit abvoe vertebral level
* T&L Spine: exit below vertebral level
57
A 32 year old man sustains an incomplete spinal cord injury characterized by ipsilateral impaired motor function and proprioception and contralateral pain and temperature sensation. What is the most likely clincial syndrome?
Brown-Sequard Syndrome
58
Describe the blood supply to the spinal cord.
* Cord itself
* One anterior (medial) spinal artery
* Two smaller posterior spinal arteries
* Form _vasocorona_
* __vasocorona can join levels vertically, but cannot provide enough blood supply to combat an occlusion in the a. of adamciewicz
* Aorta gives off segmental arteries in cervical spine
* Thoracic and lumbar spine provied by radicular arteries
59
Where do spinal artieres recieved blood supply in the thoracolumbar region?
Radicular arteries
* Posterior intercostal arteires\> dorsal branch\> spinal branch\> anterior and posterior radicular branches
60
What tract is the main descding motor pathway in the cervical spinal cord?
Lateral Corticospinal Tract
61
Disc herniation between bodies of L3 & L4 located lateral to the neural foramen, most likely causes clinical signs and symptoms involving which nerve root?
L3
62
What are the Extrinsic Craniocervical Ligaments?
1. Ligamentum Nuchae
2. Anterior Atlantoccipital Membrane (continuation of ALL)
3. Atlantoocciptial & Atlantoaxial joint capsule
63
What are the intrinsic craniocervical ligaments?
* 3 layers anterior dura
1. Tectorial Membrane
* Connects posterior body of axis to anterior foramen magnum. Cephalad continuation of PLL
2. Crucate Ligament (transverse atlantoaxial ligament, transverse bands)
3. Odontoid Ligaments (alar and apical)
64
What are the atlantoaxial ligaments?
1. Transverse atlantoaxial ligament (strongest component)
2. Alar Ligament
3. Vertical Bands
4. Apical Ligaments
65
What combined distance of lateral mass overhang in the setting of a Jefferson Fracture represents rupture of transverse atlantoaxial ligament?
Controvertial. 6.9 vs 8.1 mm
66
What amount of prevertebral swelling is indicator for injury?
* \<3mm normal (\<5mm normal in children(
* 3.5-5mm - injury to the transverse atlantoaxial ligament. Alar and apical ligment intact
* \<5mm - injury to transverse and alar ligments, and tectorial membrane
67
What are Harris Measurements used for? How do you measure?
* Used ot assess occipitoatalantal dissociation
* Bastion Dens Interval (BDI)
* Bastion to Posterior Axial Interval (BAI)
* Both should be \<12 mm
68
What is Power's ratio and what is it used to measure?
* Measures occipitoatlantal dissociation
* Power's Ratio = Dens to Opsition Distance / Bastion to C1 Arch Distance
* Ratio \>1 is abnormal
69
What measurements can you use to determine occipitoatalantal dissociation?
1. Harris Measurements (BDI, BAI)
2. Power's Ratio
70
What are the types of Occipital Condylar Injury?
1. Primarily Bony - large bony fracture
2. Primarily Ligamentous - flecks/avulsion fractures
71
What is a Jefferson Fracture?
* Fracture of the lateral mass/C1 ring
* Lateral mass overhang (sum of bilateral) \>6.9 or 8.1 mm = injury to transverse atlantoaxial ligament making injury unstable
72
How do you determine atlantoaxial instability?
* Sagittal instability
* Atlanto Dens Interval (ADI) \>10
* Posteiror Antlanto Dens Interval (PADI) \<=14 predictor of neurological deterioration
* Rotatory Instabilty
73
Which joints of the spine are synovial?
1. Atlantooccipital
2. Lateral Atlantoaxial Joint
3. Central Atlantoaxial Joint
4. Facet Joints
74
What are the radiographic signs of a rheumatoid c-spine?
1. Atlantoaxial subluxation (anterior subluxation C1 on C2)
* ADI \>10mm, or PDI \<=14mm
2. Basilar Invagination
3. Subaxial Subluxaiton
## Footnote
*\*usually these signs present in order above*
75
What are risk factors for nonunion of type 2 odontoid fractures?
1. \>6mm tranlation
2. \>10 degrees angulation
76
What is a Hangman's Fracture?
* C2-C3 spondylolisthesis secodnary to fracutre of both pedicles/pars of C2
* Can measure degree of displacement using:
* Angulation between infereior endplates of C2 and C3
* Angulation between posterior aspect of bodies between C2 and C3
* Displacement between posterior aspects of bodies of C2 and C3
77
What is the radiographic hallmark of a rheumatoid c-spine?
Erosion of the Dens
78
How do you mesure atlanto axial impaction (basilar invagination) with and without erosion of the dens?
WITHOUT EROSION
1. Odontoid above McRae's Line (bastion to opisthion)
2. Odontoid \>=4.5mm above McGregor's line (hard papate to opisthion
WITH EROSION
1. Ranawat's Method
* Measure form line going through middle of pedicle to line through transvers axis of C1
* \<=15 in men, \<13mm in women
2. Redlund-Johnell's Method
* Measure between line from base of C2 to line connection hard palate to opisthion (McGregor's Line)
* \<=35 in men, \<=29 in women
79
What is the criteria for determining subaxial subluxation?
* \>4mm subluxation
* \>20% listhesis
80
What is the CMA angle and what does it represent?
* Cervicomedullary angle= Line along anteiror aspect of cervical spinal cord and medulla
* Normal = 135-175 degrees
* \<135 degrees is consistent with cervicomedullary compresssion, myelopathy or C2 radiculopathy
81
What are signs of pathologic subluxation in the pediatric c-spine?
1. Anterior swelling
2. Constant interspinous distances
3. Spino-laminar line normal in flexion
4. Subluxation reduces with extension
5. Swischuk's Line
82
What is os odentidum
* Separate of ossificaiton called os terminale appears aroudn age 3 and fuses ot body of dens by age 12.
* Failure of fusion results in small ossicle at odontoid tip
83
What factor, when increased, correlates to higher rates of spondylolisthesis
Increased Pelvic Incidence
84
What deformity is most predictive of disability in adult patients with scoliosis?
Sagital plane decompensation.
85
When does risk fo neurologic deficit appear in subaxial subluxation?
When canal diameter \<=14 mm
86
Pseudosubluxation of cervical spine in children is most commonly seen at what level?
C2-C3
* Subluxation between C2-C3 is normal in children \<8 years old. Seen in 40% of patients.
87
What is Swischuk's Line
* Line connecting anterior aspect of spinous process between C1 and C3
* If anterior aspect of C2 psinsous process missess this line by \>=2mm, consider pathologic subluxation (Hangman's Fracture)
* This line is only applicable when subluxation is present, if no subluxation, then is normal regardless of how far the anterior aspect of t C2 spinsous is from Swischuk's Line
88
What is Meyerding Classification of Spondylolisthesis
* Grade 1 - \<25%
* Grade 2 - 25-50%
* Grade 3 - 50-75%
* Grade 4- 75-100%
* Grade 5- Full Slip
89
What is Horner's Syndrome?
* Injury to symphathetic ganglions
* Located 10.6mm from medial boards of longus colli
* Symptoms:
* Ptosis (droopy eyelid)
* Miosis (constricted pupil)
* Anhidrosis (absence of skin sweating
90
What are the lower motor neuron (LMN) signs?
* Weakness
* Decreased muscle tone
* Decreased deep tendon reflexes
* Fibrillations/Fasciculations
91
Which vertebrea are bifid?
C2-C6
92
Where do you place Halo Pins? What are the dangers?
* Anterior: 1cm aboce orbital ridge, in lateral 2/3 of orbit
* Dangers:
* Supraorbital N.
* Suprtrochlear N.
* Frontal Sinus
* Temporalis Muscle
* Posterior: diagonally opposite to the anterior pins. Posterior placement less critical
* usually above ear pinnae
93
What injuries are Halo Traction best suited for?
* Upper cervical fractures.
* Does not control lateral bend and not well suited for lower cervical fractures
94
What are upper motor neuron (UMN) signs?
* Spasticity
* Clonus
* Hyperreflexia
* Upgoing Babinski/ Positive Hoffman's
* Pronator Drift
95
List surface landmarks for vertebral level.
* Mandible C2-3
* Hyoid Cartilage C3
* Thyroid Cartilage C4-5
* Cricoid Cartilage C6
* Vertebral Prominence C7
* Sacpular Spine - T7
* Renal A L2
* Top of Illiac Crest - L4
* Illiac Bifurcation S1
96
What are the 3 columns of the spinal column?
* Anterior ( ALL, anterior body)
* Middle (posterior body, PLL)
* Posterior (posterior elements, ligamentum flavum, supraspinous and infraspinous ligmanets)
97
What nerve palsy is most commonly seen with Halo Traction? Other palsies seen?
* Most common Cranial Nerve VI (Abducens) palsy
* Controls lateral movement of eyes
* Can kink at bony ridge of cavernous sinous and petrophenoid ridge
* Other palsies seen
* Glossopharyngeal (IX)
* Vagus (X)
* Spinal Accessory (XI)
98
What is the ASIA motor muscle groups tested?
* C5 elbow flexors
* C6 wrist extensors
* C7 elbow extensors
* C8 finger flexion
* T1 finger abductors
* L2 hip flexors
* L3 knee extensors
* L4 ankle dorsiflexion
* L5 great toe extension
* S1 ankle plantar flexion
99
Injury to the superior hypogastirc plexus in the retroperitoneal approach to the L-Spine can cause what?
* Retrograde ejaculation
100
C1C2 joint produces most of what ROM? How much?
Rotation, 50%
101
At what level is the spinal cord the largest in the c-spine?
C2
102
Occiput-C1 joint provides most of what ROM? How much?
Flexion/Extension, 50%
103
Where do you find mamillary processes?
* Found in L-spine
* Project from superior articular processes
* Attacment of the mutifidus muscle
104
How many sacral formaina are there?
4
105
What is the most common site of disc herniation. Second most common?
* Most common - L5S1
* Second most - L4L5
106
What are the two layers of the intervertebral discs, and which layer contains nerve endings?
1. Annulus Fibrosis ( Type 1 Collagen)
* Has nerve endings
2. Nucleus Pulposis (Type 2 Collagen)
107
What is the largest pedicle in the upper spine? L-Spine?
* Upper spine - T1
* L-Spine - L5
108
What is the ligamentum nuchae?
* C-Spine supraspinous ligment.
* The regular supraspinous ligament runs from C7 to sacrum.
109
Continuation of Ligamentum flavum from C1 to skull is called what?
Posterior atlantoaxial membrane
110
Continuation of ALL from C1 to skull is called what?
Anterior Atlantooccipital Membrane
111
Coninuation of PLL from C1 to skull is called what?
Tectorial Membrane
112
What is the watershed area of the spinal cord?
T4-9
Narrowest spinal canal with poorest blood supply.
113
What is a teardrop fracture?
* Fracture of the anterior inferior endplate
* Flexion type unstabel and associated with SCI
* Extension type is stable
114
What is Chassagrac's Tubercle?
* Carotid tubercle: anterior tubercle of transverse process of C6
* Where carotid and vertebral artery separate
115
Name the 3 fascial layers to pass through in the Smith Robinsion approach from superficial to deep.
1. Deep cervical fascia
2. Pretrachial fascia
3. Prevertebral fascia
116
Is Smith Robinson better to approach from left or right, why?
* Better to approach on left due to predictable course of recurrent laryngeal nerve.
## Footnote
*\*Evidence shows there is no difference. This is traditional teaching answer*
117
Is the inferior articular process of the facet joint anterior or posterior in the cervical spine?
Posterior
118
In what percentage of the population does the vertebral artery run in C7 vertebral foramen?
7.5%
119
What are the contents of the carotid sheath?
1. Common Carotid Artery. (+/- internal carotid artery, internal jugular vein)
2. Vagus N.
3. Deep Cervical Lymph Nodes
## Footnote
*\*From Medial to lateral artery, nerve, vein*
120
Label the following Diagram
121
List the Superficial Back Muscles
* Move upper extremity.
1. Trapezius
2. Latissimus Dorsi
3. Levator Scapulae
4. Rhomboid Major
5. Rhomboid Minor
122
List the Intermediate Back Muscles
* Respiratory muscles, insert onto ribs
1. Levatores Constatorum
2. Serratus Posterior Superior
3. Serratus Posterior Inferior
123
List the Deep Back Muscles
* Move trunk and back.
1. Spenius
2. Errector Spinae
1. Illiocostalis
2. Longissimus
3. Spinalis
3. Transversospinalis
1. Semispinalis
2. Multifidus
3. Rotatores
