Spine Flashcards
Describe modic type end plate changes?
Type 1 - Oedem - T1 dark, T2 bright
Type 2 - Fat - T1 bright, T2 bright
Type 3 - Scar - T1 dark, T2 dark
Difference between residual disc and scar ?
Both T1 low
post contrast scar will enhance
What is Jefferson fracture
Burst fracture of C1
Axial loading - jumped into a pool
What is hangmans fracture?
Bilateral pedicles or pars fracture of C2
Anterior subluxation of the C2 body, canal widening so cord damage uncommon
associated avulsion fracture of the Anterio inferior corner of C2 (ALL)
What is teardrop fracture?
Anterior inferior corner
Flexion type (more common)
Strongly associated with anterior cord syndrome = Immediate paralysis
hyperextension injury, stable.
Rarely Posterior cord syndrome = Proprioception gone
DDX limbus
Clay-shovelers fracture?
Avulsion of the spinous process at C7 or T1
Chance fracture?
Horizontal fracture through the thoracolumbar spine (Seatbelt)
Types of odontoid fracture?
Type 1 - upper part (rare but usually stable)
Type 2 - base (unstable and most common)
Type 3 - through the dens and into the body of C2(unstable, but best prognosis for healing)
which type of os odontoideum fuses to the clivus?
Dystopic
Orthotopic is os right on top of the dens
Parone to subluxation and instabilty.
Associated with Morquios syndrome
Key differences between malignant vs benign compression fractures?
Malignant
-Convex posterior vertebral body cortex
-Involves posterior elements
-Epidural/paraspinal mass
-Multiple lesions
Benign
-Retropulsed fragments
- Transverse T1 and T2 dark band
What are open spinal dysraphism’s and the types?
Spina bifida Aperta
=Neural tissue is exposed through a defect in bone and skin.
Cord is going to be tethered
Myeloceles = neural placode is flush with skin
Myelomeningoceles = More common (98%) = neural placode protrudes above the skin.
What are closed spinal dysraphism with subcutaneous defects ?
Spina bifida occulta
= The defect is covered by skin
Meningocele = herniated CSF sac through defect in posterior elements. can be anterior sacrum
Lipomyelocele/lipomyelomenigocele = Lipomas with dural defect. Cord is tethered
Terminal myelocytsocele = herniation if terminal syrinx into a posterior meningocele.
What is cord regression ?
spectrum of partial or complete agenesis of the lumbosacral or coccyx
*Maternal diabetes
‘Blunted sharp’ high terminating cord is classic
‘shield sign’ - unopposed iliac bones
Associations with VACERTL and currarino triad
Elderly with progressive radiculomyelopathy. MRI - Abnormally enlarged, T2-hyperintense distal cord covered with dilated pial vein flow voids?
Type 1 Dural AVF
Most common type
Between the radiculomedullary arteries and veins
SAH and MRI shows intramedullary nidus. what type of spinal AVMs?
Type 2
INTRAMEDULLARY NIDUS. Present with SAH
From anterior or posterior spinal arteries
Associated with cutaneous angiomas - HHT and KTS
Which type of Spinal AVM can occur in child with Nidus with extramedullary and extraspinal extensions?
Type 3
Rare and terrible prognosis
intramedullary and extramedullary
Ventral fistula and intradural site of AVF?
Type 4 (Perimedullary Fistula)
Intradural extramedullary site of AVF.
Near the conus
Features of TB spine/Potts disease
Tends to Spares the disc spaces
Mutli-level thoracic skip involvement
‘Calcified psoas abscess’
Gibbus vertebrae with relatively intact intervertebral discs, large paraspinal abscesses
Mutliple short segment (<2cm) spinal lesions, affecting part of the cord. Predominantly in the cervical cord?
MS
Lesions can enhance when acute
Cord atrophy is large burden
Central cord lesion > 2 vertebral segments in length with eccentric enhancement in thoracic region.
Transverse myelitis
At least 2/3 of cross section of the cord affected (WM and GM).
‘Expansion of central cord’
Acute partial = lesions < 2 segments
Acute complete = lesions > 2 segments
** Acute partials are higher risk for developing MS**
DDx MS
- smaller usually confined to 1-2 vertebral levels
- affecting less than half of the cross-sectional area of the cord
DDx ADEM
-usually demyelination in WM of the brain
- if in spine, spares grey matter
Differences between MS and ADEM?
ADEM
-Favours the spinal dorsal WM
- Cranial nerve enhancement
- Basal ganglia and Pons lesions - unusual for MS
-anti-MOG igG +ve (50%)
Long segments (3 levels) lesions that involve the full transverse diameter of the cord?
NMO
Enhancement of the optic nerves
limited brain parenchymal involvement
Difficult to distinguish from ADEMs on first presentation
Bilateral symmetrically increased T2 signal in the dorsal columns without enhancement.
Subacute combined degeneration
Vit b12 def
‘inverted V sign’
Looks the same as
= AID patients = HIV Vacuolar myelopathy
T2 hyperintensity long segment that involves anterior horn cells and central cord.
Spinal cord infarct
‘Owl eye’ appearance (grey matter most vulnerable)
anterior spinal artery is commonest
Look for vertebral body infarcts 7
Will have diffusion restriction
