Degenerative Disc Disease Flashcards
What is the most common location of DDD in the cervical and lumbar spine?
Cervical = C5/C6 Lumbar = L4/L5
What is the clinical term for DDD that affects the outer disc? Inner disc?
Outer = spondylosis deformans Inner = intervertebral chondrosis
What radiographic feature marks spondylosis deformans (DDD of the outer disc)?
Osteophytes
What radiographic feature marks intervertebral chondrosis (DDD of the inner disc)?
Reduced IVD space
Knutson’s vacuum phenomenon is associated with what condition?
IVD ostechondrosis
What is IVD osteochondrosis?
Primary degeneration of the nucleus pulposus
What is the underlying cause of an osteophyte?
Breakdown at site of attachment of outer annular fibers of the disc to the vertebral margin (disc bulging)
What is the vacuum (Knutson’s phenomenon) seen with DDD?
Radiolucent collections of nitrogen gas within annular fibers
Where is the vacuum phenomenon best seen?
Anterior margin of IVD on extension films
What change to the endplate is seen with DDD?
Subchondral sclerosis
What can subchondral endplate sclerosis due to DDD become confused with?
Infection or blastic tumor
What are the 4 major radiographic signs of DDD?
1 decreased disc height
2 osteophytes
3 end plate sclerosis
4 vacuum
Type One medic end plate changes are more common in what are of the spine?
Cervicals
Which type of modic end plate changes is more common in the lumbar spine?
Type Two
What color is CSF fluid on T1 MRI? T2?
T1 = black T2 = white
Which modic end plate change of DDD is associated with sclerosis?
Type III
Which modic end plate change of DDD is associated with inflammation?
Type I
Which modic end plate change of DDD is associated with fat?
Type II
Describe the MRI parameters for each modic end plate type.
Type I = dark T1, bright T2
Type II = bright T1, bright T2
Type III = dark T1, dark T2
What is an important differential diagnosis to considered with Modic Type One?
Infection (presence of end plate destruction with increased signal intensity of the disc)
What other condition can appear similar to DDD but only present on one side of the disc?
Chordoma
What is the easiest way to tell if a compression fracture is acute?
Presence of marrow edema
At what age do most pars fractures occur?
8-12 years
What is usually the cause of pars fractures from 8-12 years of age?
Stress fractures (not injury)
About how long of a time span off away from stressors is necessary to allow for pars fracture healing?
6 months
What is becoming the gold standard for imaging pars interarticularis stress fractures?
MRI
Posterior joint arthritis is associated with subluxation in which direction?
Anterior
Degenerative disc disease is associate with subluxation i which direction?
Posterior
What is the most common location for a degenerative spondylolisthesis? Second more common?
#1 = L4/L5 #2 = L5/S1
What is the gender bias associated with degenerative spondylolisthesis?
Females
At what age is a degenerative spondylolisthesis most likely?
Over 40
What is the most common location for DDD of the cervical spine? Second most common?
#1 = C5/C6 #2 = C4/C5
Which Roentgenometric is seen at the levels where DDD is more common in the cervical spine?
Ruth Jackson stress lines
What is the term for the chucks of bone formed in the outer annular fibers that are seen with DDD of the cervical spine?
Intercalary ossicles
What radiographic sign appears on a lateral view when uncinate hypertrophy due to degeneration of the cervical spine?
Pseudo fracture through vertebral body due to lateral projection
What is the most common location for a pseudofracture sign to appear due to uncinate hypertrophy following DDD of the cervical spine?
C3-C7 (mid to lower cervicals)
What is the major issue with uncinate hypertrophy?
May invade IVF and affect nerve roots
Why is it possible for and enlarged uncinate to invade the IVF but not affect the nerve root?
Nerve exits from only superior aspect
Degeneration of the zygapophyseal joints is most common in what areas of the spine?
Lower lumbar, middle cervical, and upper and middle thoracic spine
What is the cause of an intercalary ossicle?
Annulus degeneration (NOT fracture osteophytes)
What condition could an intercalary ossicle get confused with?
Limbus vertebra
What is the criteria for Scheuermann’s disease?
Decreased disc space and endplate irregularities at at least 3 contiguous vertebrae each with wedging of 5 degrees or more
What is the age of onset for Scheuermann’s disease?
13-17
Why is Scheuermann’s disease an issue?
Can lead to premature DDD, pain, cosmetic deformity
What is another name for Scheuermann’s disease?
Juvenile Discogenic Disease, Thoraco-lumbar Scheuermann’s disease
How frequent is Scheuermann’s disease?
Up to 20-40% of those presenting to MRI with back pain will have it
What causes Scheuermann’s disease?
Failure of embryologic vascular channels, centrum defects, notochord clefts to disappear leaving the endplate defects
What kind of change to the curvature of the thoracic spine is seen with Scheuermann’s disease?
Hyperkyphosis
In what population do Schmorl’s nodes usually occur?
Young children (insignificant)
When can the occurrence of Schmorl’s nodes become worrisome?
In adults indicating endplate fractures
Where in the thoracic spine do osteophytes usually form?
Mostly anterior and right sided
In what area of the spine do the disc rarely calcify?
Thoracics
What is the term for very dense nucleus pulposus calcification?
Ochronosis
What part of the disc calcifies with CPPD, hypervitaminosis D, or hemochromatosis?
Annulus fibrosis
Transient intervertebral disc calcification that usually spontaneously regresses is common with what population and at what spinal area?
Children in the cervical spine
What is the most severe way in which pain is felt from degeneration?
Direct press on subchondral bone
What is the eponym for DISH?
Forestier’s disease
What ligament is primarily involved with Diffuse Idiopathic Skeletal Hyperostosis?
Anterior longitudinal ligament (ALL)
What is the age and gender bias for DISH?
Males over 50
What underlying metabolic condition is associated with the presence of DISH?
Diabetes (13-49%)
What GI issue is associated with DISH?
Dysphagia (20%)
How common is OPLL with DISH patients?
40%
Where in the spine is DISH most commonly seen?
Middle/lower thoracics, upper lumbars, and lower cervicals
What is an enthesopathy?
Pathological osseous proliferation at tendon ligament insertion
The absence of what radiographic feature when viewing DISH rules out the diagnosis of ankylosing spondylitis (AS)?
Bilateral sacroilitis (also preservation of disc height)
The “flowing candle wax appearance” is seen with what condition?
DISH
What is unique about the discs involved with DISH?
Height is preserved (minimal evidence of degeneration)
Which ALL ossification is thicker: that in AS or DISH?
DISH (AS presents as thin line)
Why is OPLL more severe than DISH?
Can put pressure onto cord inducing neurological symptoms (myelopathy)
What kinds of cord symptoms can be present with severe OPLL?
Anterior cord syndrome: sensory/motor disturbances of the legs, difficulty walking, paresthesia and diminished tactile senses
What is a common treatment for OPLL?
Laminectomy (to decrease pressure and create more room for cord)
