Articles

Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.

43 results found
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Anterior vertebral body beaking

Anterior vertebral body beaking occurs in a number of conditions and may emanate from the central portion or the lower third of the vertebral body. Middle third Morquio syndrome 1 (middle for Morquio) Lower third Hurler syndrome 2 achondroplasia 3 pseudoachondroplasia 4 cretinism 5 Down ...
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Basilar invagination

Basilar invagination, also called basilar impression, is a congenital or acquired craniocervical junction abnormality where the tip of the odontoid process projects above the foramen magnum.  Terminology The terms basilar invagination and basilar impression are often used interchangeably becau...
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Bone within a bone appearance

Bone within a bone is a descriptive term applied to bones that appear to have another bone within them. There are numerous causes including: normal thoracic and lumbar vertebrae (neonates and infants) growth recovery lines (after infancy) cortical splitting and new periostitis sickle cell d...
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Cervical spine injury

Cervical spine injuries can involve the cervical vertebral column, intervertebral discs and cervical spine ligaments, and/or cervical spinal cord. The cervical spine accounts for ~50% of all spinal injuries.  Epidemiology 5-10% of patients with blunt trauma have a cervical spine injury 1.  Pa...
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Coronal vertebral cleft

Coronal vertebral clefts refer to the presence of radiolucent vertical defects on a lateral radiograph.   Epidemiology It is most often seen in premature male infants 1,3. As they can occur as part of normal variation (especially in the lower thoracic-upper lumbar spine of premature infants) t...
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Craniovertebral junction anomalies

Craniovertebral junction (CVJ) anomalies can be congenital, developmental or due to malformation secondary to any acquired disease process. These anomalies can lead to cranial nerve compression, vertebral artery compression and obstructive hydrocephalus. Pathology The craniovertebral junction ...
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Diffusely increased bone marrow FDG uptake

A diffuse homogeneous bone marrow FDG uptake usually reflects hyperplastic bone marrow which can be seen in the following conditions: therapy-related granulocyte colony-stimulating factor (G-CSF) post-chemotherapy erythropoietin pathological process myelodysplastic syndromes beta-thalasse...
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Diffuse T1 bone marrow signal loss

Diffuse T1 vertebral bone marrow signal loss is associated with replacement of fatty marrow by edema or cellular tissue. T1-weighted imaging without fat suppression is one of the most important sequences for distinguishing between normal and abnormal bone marrow. In the case of homogenous involv...
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Dural ectasia

Dural ectasia refers to ballooning or widening of the dural sac which can result in posterior vertebral scalloping and is associated with herniation of nerve root sleeves. Clinical presentation Patients with dural ectasia may present with low back pain or radicular pain in the buttocks or legs...
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Erosion of the odontoid process (differential)

Erosion of the odontoid peg can result from a number of pathological entities: inflammatory arthropathy rheumatoid arthritis: classic 1,2 systemic lupus erythematosus crystal arthropathy calcium pyrophosphate arthropathy (CPPD): relatively common gout non-inflammatory arthropathy: osteoar...
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Gibbus deformity

A gibbus deformity is a short-segment structural thoracolumbar kyphosis resulting in sharp angulation. Pathology Etiology There are a number of causes which can be divided into congenital and acquired. Congenital achondroplasia cretinism (congenital hypothyroidism) Apert syndrome Coffin-...
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Holocord presentation

Holocord presentation refers to a process which involves the spinal cord, from cervicomedullary junction to the tip of the conus. It does not relate to a specific condition nor does it distinguish between involvement by cystic expansion or solid tumor, or by a combination of both. It merely deno...
Article

Intervertebral disc calcification

Intervertebral disc calcification is a non-specific finding seen in numerous conditions. Epidemiology It may be observed in pediatric 5 as well as adult populations. Pathology Etiology degenerative: relatively common and may occur in up to 6% of routine abdominal radiographs in adults post...
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Intradural extramedullary spinal tumors

Intradural extramedullary neoplasms are located outside the spinal cord but within the dural sheath.  Epidemiology The majority (70-80%) of spinal canal tumors are intradural extramedullary 1. Clinical presentation Patients present with signs and symptoms of spinal cord or nerve root compres...
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Longitudinally extensive spinal cord lesion

Longitudinally extensive spinal cord lesions (LESCL), also known as longitudinally extensive transverse myelitis (LETM), represent extensive involvement of the spinal cord, with abnormal T2 signal traversing at least three vertebral body segments in length. Differential diagnosis They are typi...
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Loss of intervertebral disc space (differential)

Loss of intervertebral disc space can be due to a variety of causes: degenerative disc disease of the spine: most common cause trauma diskitis neuropathic spondyloarthropathy dialysis related spondyloarthropathy ankylosing spondylitis ochronosis crystal deposition diseases sarcoidosis ...
Article

Meningocele

Meningoceles are protrusions of the meninges through a defect or weak point in the skull or spine, usually involving the soft tissues beneath the surface of the skin. They are typically categorized into congenital, iatrogenic (e.g. following a craniotomy, sinus surgery, or as a laminectomy compl...
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Neoplasms of the cauda equina (differential)

The differential diagnosis for masses of the cauda equina region is often considered separately to the remainder of the spinal cord. It is often difficult to determine whether masses in this region are intramedullary or intradural-extramedullary. Most common tumors myxopapillary ependymoma by...
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Nerve root enhancement

Nerve root enhancement is phenomenon described on post contrast MRI scans that can be observed in a number of situations. Common causes post-operative states post-operative nerve root enhancement arachnoiditis leptomeningeal metastases disseminated spinal leptomeningeal metastases HIV vac...
Article

Osteoarthritis of the vertebral column

Osteoarthritis of the vertebral column, also known as spondylosis deformans, is common and usually merely referred to as spinal "degenerative change". Complications such as spinal stenosis are important to recognize.  Radiographic features The hallmark of osteoarthritis in the spine, as is the...
Article

Parasyndesmophytes

Parasyndesmophytes or floating syndesmophytes are, as the name suggests, paravertebral dystrophic soft tissue calcifications or heterotopic ossifications. Pathology They are known to be seen in psoriatic arthritis and reactive arthritis 4. Radiographic features Initially they begin at a dist...
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Posterior vertebral fusion anomalies

Posterior vertebral fusion anomalies are relatively common and should not be mistaken for fractures. They are thought to be both developmental and pathological (e.g. spondylolysis) but are typically asymptomatic and incidental, and considered as anatomical variants. There are six types of poster...
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Powers ratio

The Powers ratio is a measurement of the relationship of the foramen magnum to the atlas, used in the diagnosis of atlanto-occipital dissociation injuries. The ratio, AB/CD, is measured as the ratio of the distance in the median (midsagittal) plane between the: basion (A) and the posterior spi...
Article

Primary bone tumors of the spine

The most common tumor of the spine is metastatic deposits. A number of both benign and malignant tumors may arise primarily from the spine. Benign osteoid osteoma osteoblastoma osteochondroma giant cell tumor (GCT) aneurysmal bone cyst (ABC) eosinophilic granuloma (EG) hemangioma Malign...
Article

Retrolisthesis

The term retrolisthesis (more rarely the synonyms retrospondylolisthesis or posterolisthesis) refers to posterior displacement of a vertebral body relative to one below. Pathology Causes include: trauma facet joint osteoarthritis congenital anomalies: e.g. pedicle underdevelopment Radiogra...
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Retropulsed fragment

A retropulsed fragment is any vertebral fracture fragment that is displaced into the spinal canal, thereby potentially causing spinal cord injury. They usually arise from the vertebral body with or without a portion of the pedicle, and are displaced posteriorly, hence the prefix 'retro'.
Article

Scheuermann disease

Scheuermann disease, also known as juvenile kyphosis, juvenile discogenic disease 11, or vertebral epiphysitis, is a common condition which results in kyphosis of the thoracic or thoracolumbar spine. The diagnosis is usually made on plain film. Epidemiology occurs in ~5% (range 0.4-8%) of the ...
Article

Spinal cord compression

Spinal cord compression is a surgical emergency, usually requiring prompt surgical decompression to prevent permanent neurological impairment. Pathology Etiology There are numerous causes of cord compression. These can be divided according to the location of the compressing mass: interverteb...
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Spinal dysraphism

Spinal dysraphisms refer to a broad group of malformations affecting the spine and/or surrounding structures in the dorsum of the embryo. They are a form of neural tube defect. Pathology The neural tube is formed by the lengthwise closure of the neural plate, in the dorsum of the embryo. The ...
Article

Spinal epidural mass

The differential diagnosis for a spinal epidural mass includes: epidural metastasis epidural abscess herniated nucleus pulposus epidural hematoma epidural arteriovenous malformation epidural angiolipoma epidural lipomatosis
Article

Spinal fractures

Spinal fractures are usually the result of significant trauma to a normally formed skeleton, or the result of trauma to a weakened spinal column. Examples include: Jefferson fracture: ring fracture of C1 hangman fracture: bilateral pedicle or pars fracture of C2 dens fracture flexion teardro...
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Spinal hematoma

Spinal hematomas are a rare clinical entity and are often idiopathic. Prompt diagnosis and treatment are crucial, lest they cause permanent neurological damage. Identifying the location of the hematoma is important for treatment, as is distinguishing it, to the extent possible, from other entit...
Article

Spinal metastases

Spinal metastases is a vague term which can be variably taken to refer to metastatic disease to any of the following: vertebral metastases (94%) may have epidural extension intradural extramedullary metastases (5%) intramedullary metastases (1%) Each of these are discussed separately. Below...
Article

Spinal vascular malformations

Spinal vascular malformations (SVM) are rare but knowledge of them is important as if undiagnosed and untreated they can lead to serious complications.  Pathology There are two main types of SVMs 1,2: spinal arteriovenous fistula (AVF): 70% of SVMs pial: small, large, or giant dural AVF (DA...
Article

Subluxed facet joint

Subluxed facet joint is the mildest form of facet dislocation in which the ligamentous injury leads to partial uncovering of facet joint (c.f. complete uncovering in perched facet). This results in mild anterior displacement of one vertebral body on another (anterolisthesis).
Article

Syndesmophyte

Syndesmophytes are calcifications or heterotopic ossifications inside a spinal ligament or of the annulus fibrosus.​ They are seen in only a limited number of conditions including:  ankylosing spondylitis ochronosis fluorosis reactive arthritis psoriatic arthritis They can be classified as...
Article

Torticollis

Torticollis (wryneck) is a clinical finding of head tilt with or without rotational spinal malalignment. It is not a diagnosis in itself and there are a wide range of underlying conditions. It is most common in the pediatric age group.  Pathology Torticollis can be acute (<1 week) or chronic (...
Article

Traumatic spinal cord injury

Traumatic spinal cord injury can manifest as a wide variety of clinical syndromes resulting from damage to the spinal cord or its surrounding structures. It can result from minor injury if the spine is weakened from disease such as ankylosing spondylitis or if there is pre-existing spinal stenos...
Article

Unilateral facet dislocation

Unilateral facet dislocation is a relatively stable type of facet dislocation. Pathology Mechanism Flexion/distraction associated with rotation. The inferior articular facet of vertebral above moves over the superior facet of the vertebral below and becomes locked. It usually affects C4-C5 or...
Article

Vertebral body mass

The differential diagnosis for a vertebral body mass is broad and may range from a completely benign, sclerotic enostosis (bone island) to a malignant primary bone tumor. Classification Broadly, these lesions can be separated into: non-neoplastic lesions primary bone tumors secondary metast...
Article

Vertebral scalloping

Vertebral scalloping is a concavity to the posterior (or less commonly anterior) aspect of the vertebral body when viewed in a lateral projection. A small amount of concavity is normal, as is concavity of the anterior vertebral body (see vertebral body squaring). Posterior scalloping Causes of...
Article

Vertebra plana

Vertebra plana (pleural: vertebrae planae), also known as the pancake or silver dollar or coin-on-edge vertebra, is the term given when a vertebral body has lost almost its entire height anteriorly and posteriorly, representing a very advanced compression fracture. Pathology It can occur in a ...
Article

Winking owl sign (spine)

The (absent) pedicle sign, also called the winking owl sign, occurs on plain film when a pedicle is absent. The term, winking owl sign, where the missing pedicle corresponds to the closed eye, the contralateral pedicle to the other open eye, and the spinous process to the beak of the animal on ...

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