Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
28 Cards in this Set
- Front
- Back
|
1. What are the radiographic findings of DISH?
|
1.
- Paravertebral ossification involving 4 contiguous vertebral bodies. - Normal SI joints - Ossification of the posterior longitudinal ligament. - Enthesopathy: ligamentous and tendinous calcification and ossification. |
|
|
1. What is the DDX of ivory vertebral body?
2. What is the DDX if the entire spinal column is involved? 3. What malignancies give you osteoblastic mets? |
1. Osteoblastic metastases, lymphoma, chronic infection, Paget's disease. Less likely osteosarcoma.
2. Diffuse mets, renal osteodystrophy, osteopetrosis, mastocytosis, myelofibrosis, fluorosis. 3. Prostate, carcinoid, medulloblastoma, neuroblastoma, breast, bladder, nasopharynx. 4. Densely sclerotic osteophytes which project into the paravertebral soft tissues at the attachment of ligaments, tendons, and muscles. |
|
|
What is the DDX of calcification of the disk?
|
1. Ochronosis: 2/2 absence of homogentisic acid oxidase leading to excessive production and deposition of homogentesic acid in cartilage and other connective tissues.
2. CPPD crystal depostion dz 3. Hemochromatosis 4. HyperPTH 5. Acromegaly 6. Poliomyelitis 7. Amyloidosis 8. Spinal fusion |
|
|
What criteria are used to make the diagnosis of cervical spinal stenosis?
|
The caliber of the cervical canal can be assessed by two methods on a lateral radiograph.
METHOD 1: canal is measured from the posterior cortex of the vertebral body to the spinolaminar line. Symptoms of cord compression occur when the measurement is less than 10 mm. NOTE: This technique does not correct for magnification, rotation, or variability in body size. METHOD 2: Pavlov ratio. In this method, the sagittal diameter of the spinal canal is divided by the sagittal diameter of the corresponding vertebral body. A ratio of 0.8 or less is considered significant and highly suggestive of congenital cervical spine stenosis. |
|
|
1. What are the imaging findings of Paget's disease?
2. What can happen if Paget's affects the base of the skull? |
1.
-Thickening of thr cortex produces a classic "picture frame" appearance. - Coarsening of the vertical trabeculation contributes to an increased density of the vertebral body. 2. Basilar imagination. The bone is relatively soft and allows the skull to settle. |
|
|
1. What is the Dennis 3 column model of the spine?
2. What constitutes an unstable fracture? |
The spine is divided into three columns:
- Anterior column: composed of the anterior half of the vertebral body and disk, anterior annulus fibrosus, and anterior longitudinal ligament. - Middle column: composed of the posterior vertebral body and disk, posterior annulus fibrosus, and posterior longitudinal ligament. - Posterior column: composed of the posterior osseous and ligamentous structures. 2. Unstable fractures are defined as injuries in which two of the three columns are involved. Often, when the middle column is involved, the injury is unstable when caused by axial loading which may lead to a burst fracture with retropulsion of fracture fragments into the spinal canal. |
|
|
1. What is most common benign lesion of the spine?
2. What are the imaging appearance of a typical hemangioma? 3. What are the imaging findings of atypical/compressive vertebral hemangioma? |
1. Vertebral hemangioma
2. Hemangiomas are composed of dilated blood vessels which cause resorption of the bony trabeculation. The remaining trabeculae thicken, yielding a classic "corduroy" appearance. On CT, the prominent vertical trabeculation is demonstrated as a polka-dot pattern inside a well-defined osteolytic area with a fatty stroma (attenuation <30 HU). 3. Atypical/compressive vertebral hemangioma is - more aggressive but much less common than a conventional hemangioma. - frequently involves the entire vertebral body and extends to the neural arch. - contain angiomatous stroma, rather than to the fatty stromaof a conventional hemangioma, and thus mimic a vascular neoplasm or metastasis. - higher attenuation value (>20 HU) - signal intensity on T2W images can be very intense. |
|
|
1. What is multiple myeloma?
2. What is a plasmacytoma? 3. What is POEMS syndrome? |
1. Primary malignancy of bone that
originates in the hematopoietic bone marrow, causing its replacement by proliferating cells that resemble plasma cells. 2. Multiple myeloma is usually widespread, but occasionally a solitary lesion may occur, referred to as a plasmacytoma. 3. Look for sclerotic mets. P = polyneuropathy O= organomegaly E= endocrine abnormality M= M protein S= skin abnormality. |
|
|
What are some features of tuberculous OSM-discitis?
|
- Periostitis = loss of cortical distinction in the anterior or posterior aspect of the vertebral body correlates with extension of infection beneath the longitudinal ligaments.
- Gibbus deformity = acute, angular kyphosis. - Infection of paraspinal soft tissues, creating abscesses particularly in the psoas muscles. - Skip lesions far removed from the initial source of infection. - Burrowing abscess = tubular tracts that course for a long distance and perforate the internal organs or communicate to the skin through a sinus. |
|
|
1. Whot is most unstable fracture of the cervical spine?
2. Where is this fracture seen? |
1. Flexion tear drop injury which is highly associated with quadriplegia.
2. The most common location for this fracture is in the lower cervical spine. The triangular teardrop fragment usually involves the anterior and inferior aspects of the body, although it may also involve the anterior and superior aspects of the body in one sixth of cases. |
|
|
1. What is OPLL?
2. Where is it most commonly seen? |
1. OPLL is characterized by the development of ossifications, either in the form of a dense strip of bone or of small plaques, in the posterior
longitudinal ligament. 2. It occurs most frequently from C3 to C5. However, it may rarely occur in the T- and L-spine. |
|
|
1. What are the 3 types of odontoid fractures?
2. Is a type 2 fracture stable or unstable? 3. Is a type 3 fracture stable or unstable? |
1.
- Type 1: fracture involves the tip of the odontoid process; 2/2 avulsion by the alar ligaments. - Type 2: the most common type; fracture occurs at the base of the odontoid process. - Type 3: fracture involving the body of C2. 2. Type 2 fractures are unstable and frequently lead to nonunion; therefore, they generally require a C1-C2 fusion. 3. Type 3 fractures are considered stable because they heal well with conservative management using a halo device. |
|
|
What is Grisel syndrome?
|
Nontraumatic atlantoaxial subluxation 2/2 retropharyngeal infection.
|
|
|
1. What is an os-odontoideum?
2. What are its imaging appearance? 3. What is the etiology of os odontoideum? 4. How and what determines stabiltiy? 5. What are some associated findings in os-odontoideum? |
1. Small ossicle that exists above a hypoplastic odontoid process.
2. Small, round or oval, well corticated ossicle located above teh tip of a hypoplastic odontoid process. 3. Most are congenital; however, it may represent non-union of a type 2 odontoid fracture. 4. Stability is determined by flexion and extension views. In severe cases of instability, the caliber of the spinal cord can be significantly reduced. Stability is dependent on the level of the cleft between the os odontoideum and the hypoplastic odontoid process. A very small dens may be unable to form a stable relationship with the atlas. 5. Coexisting abnormalities include a hypoplastic posterior neural arch and hypertrophy of the anterior arch of C1. |
|
|
What is DDX of vertebral plana?
|
MELTS
M = Mets/myeloma (NB in children) E = EG L = Lymphoma/leukemia T = Trauma/osteoporotic compression fracture S = Steroids |
|
|
1. What is a Hangman's fracture?
2. Is neurological injury commonly seen? 3. What are the different types of Hangman fractures? 4. Why should you recommend a CT when a Hangman fracture is seen on radiographs? |
1. Bilateral fracture of the neural arch of C2 caused by a hyperextension injury.
2. Because there is not encroachment of the spinal canal, neurological deficits are uncommon. 3. There are 3 types of Hangman fractures based on the relationship of C2 on C3: - Type 1: No forward displacement of C2 on C3. Fractures only involve the posterior elements. - Type 2: Anterior displacement of C2 on C3 (indicating injury to the anterior longitudinal ligament) - Type 3: anterior displacement of both anterior and posterior fragments. Generally, both type 2 and 3 require halo immobilization. 4. Hangman fractures are frequently associated with other fractures. |
|
|
1. Define atlantoaxial subluxation.
2. What is cranial settling? |
1. Anterior displacement of the atlas, causing an increased space between the dens and the anterior arch of C1. When the predental space exceeds 2.5 mm, it is called atlantoaxial subluxation.
2. Cranial settling is a process that is characterized by inferior migration of the atlas relative to the odontoid process, caused by destruction of both lateral masses of C1 and by collapse of the occipitoatlantal and atlantoaxial articulations. A clue to the diagnosis of cranial settling is recognition that the anterior arch of C1 (which normally articulates with the odontoid process) articulates with the base of the odontoid or the body of C2. |
|
|
1. What is the normal atlantodens interval in adults? Children?
2. What are the findings in atlantooccipital disassociation? 3. What is the powers ratio? |
1. 2mm in adults; 4mm in children.
2. In the vast majority of cases the skull base slides anteriorly relative to the atlas. 3. Th Powers ratio is defined by drawing a line from the tip of the foramen magnum (basion) to the back of C1 (inner aspect) and dividing it by a line drawn from the back of the foramen magnum (opisthion) to the front of C1 (inner aspect). Normal ought to be less than or equal to 1.0. |
|
|
1. What is the difference between a pars interarticularis fracture and facet joint?
|
A pars inetrarticularis fracture is located approximately 10 to 15 mm above the disk level, irregular noncorticated margin, located anterior to the facet joint and oriented in a more coronal plane.
A facet joint is located at the level of the disk, is oriented obliquely, and contains smooth cortical margins. |
|
|
Rugger Jersey appearance of spine
|
RENAL OSTEODYSTROPHY
- margins between the sclerotic and lucent portions of the vertebral body are smudgy rather than sharp - look for other findings suggestive of renal osteodystrophy -- osteomalacia, osteosclerosis, hyperPTH, dialysis catheter, etc. OSTEOPETROSIS - "Sandwich" appearance of the vertebral bodies with sharp margin between the sclerotic end plates and more lucent bone centrally. PAGET'S DISEASE - "Picture frame" vertebral body - look for overall increased density with sclerosis most marked at the periphery and a relatively lucent center. - Vertebral body enlargement, coarsened trabeculae, and increased bone density. |
|
|
Myelofibrosis
|
- bone marrow fibrosis most commonly 2/2 leukemia, lymphoma, or metastatic disease.
-initially involves sites of active hematopoiesis (vertebrae, pelvis, ribs) and later involves the proximal and distal aspects of long bones. - radiographs may be normal, but when abnormal, they will show diffuse marrow sclerosis. |
|
|
Posterior element lytic lesion
|
ABC
OSTEOBLASTOMA INFECTION (TB) - lytic lesion in the spine + adjacent paraspinal/epidural abscess - spares the intervertebral discs METASTASES - involves the posterior vertebral body first and then subsequently extends into the posterior elements. LANGERHANS CELL HISTIOCYTOSIS |
|
|
Pathologic fractures
|
Features that suggest un underlying malignant etiology:
1. Abnormal marrow signal with ill-defined margins (all fxs will demonstrate increased T2 and inversion recovery signal 2/2 marrow edema and hemorrhage but the edema in simple fxs is well-defined. 2. Abnormal marrow signal extending into pedicles (marrow edema in simple fxs is limited to the vertebral body) 3. Associated soft tissue lesion with irregular or nodular borders (smooth paravertebral soft tissue swelling is normally seen surrounding a fx) 4. Marked enhancement (mild enhancement can be seen with benign fractures). 5. Traumatic fxs tend to occur in upper lumbar spine; an underlying lesion should be suspected in a younger pt with a lower lumbar spine fx. |
|
|
Posterior vertebral body scalloping
|
DURAL ECTASIA
- NF - Marfan and Ehlers Danlos MUCOPOLYSACCARIDOSIS ACHONDROPLASIA SPINAL CORD TUMOR |
|
|
What are the causes of scoliosis?
|
1. Idiopathic - most common. Usually "S" shape
2. Neuromuscular disease: cerebral palsy. Usually a "c" shape. 3. Skeletal abnormality: hemivertebrae 4. Syndromes: neurofibromatosis 5. Postoperative/post-traumatic deformity |
|
|
What are the different types of idiopathic scoliosis?
|
1. Infantile scoliosis:
- may either be progressive or nonprogressive. - nonprogressive form presents as a thoracic convex left curve that will not exceed 30 degrees. Resolves spontaneously. - progressive form progresses to curves greater than 35° and carries a poor prognosis as these patients are prone to scoliosis-related cardiorespiratory insufficiency. 2. Juvenile form - most common in girls 4-9 years - demonstrates a right thoracic convexity - progressive and carries a poor prognosis. 3. Adolescent type: - most common form - presumed to have a genetic component (autosomal dominant). - convex right thoracic curve that usually will not exceed 30°. - Progression of the curvature occurs during growth spurts. |
|
|
1. How do you measure the Cobb angle?
2. When do you consider surgical correction? |
1. Draw lines parallel to the endplates of the two vertebral bodies that stray furthest from spinal axis, draw perpendicular lines and measure the angle at the intersection.
2. Surgical correction of the scoliosis often is not contemplated until the Cobb angle exceeds 40° after skeletal maturity. |
|
|
1. What is the etiology of Scheuermann Disease?
2. What are the imaging findings in Scheuermann Disease? |
1. Osteochondroses affecting the vertebral body epiphysis. Remember that there is a narrow, ring-like epiphysis along the superior and inferior margins of the vertebral body which is affected by Scheuermann disease.
2. - Irregularity of the endplates - Anterior wedging of the vertebral bodies resulting in kyphosis. - Loss of height of vertebral bodies and disc spaces - Endplates lose sharpness and develop a sclerotic, fragmented appearance. - CT/MRI may show multilevel Schmorl's nodes. |
