Articles
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740 results found
Article
Os odontoideum
Os odontoideum (plural: ossa odontoidea) is an anatomic variant of the odontoid process of C2 and needs to be differentiated from persistent ossiculum terminale and from a type 2 odontoid fracture. It can be associated with atlantoaxial instability.
Although it was originally thought to be a c...
Article
Anderson and Montesano classification of occipital condyle fractures
The Anderson and Montesano classification is a widely used system for describing occipital condyle fractures. It divides injuries into three types based on morphology and mechanism of injury 1-5.
Classification
type I: impacted type occipital condyle fracture
morphology: comminution of the co...
Article
Spinal meningioma
Meningiomas arising from the coverings of the spinal cord are one of the two most common intradural extramedullary spinal tumors, representing 25-30% of all such tumors 2.
This article specifically relates to spinal meningiomas. For a discussion on intracranial meningiomas and a general discus...
Article
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth (CMT) disease, also known as hereditary motor and sensory neuropathy (HMSN), refers to a heterogeneous group of inherited peripheral neuropathies rather than a single clinical entity 9.
Epidemiology
The prevalence of CMT in one Norwegian study was 82.3 cases per 100,000 peo...
Article
Chordoma
Chordomas are uncommon malignant tumors of the axial skeleton that account for 1% of intracranial tumors and 4% of all primary bone tumors.
They originate from embryonic remnants of the primitive notochord (earliest fetal axial skeleton, extending from the Rathke's pouch to the tip of the cocc...
Article
Focal fatty deposits in bone marrow
Focal fatty deposits, also known as marrow islands or replacements in the bone marrow, are well-defined focal fat islands within the bone marrow of the spine or other parts of the axial skeleton 1,2.
Epidemiology
Common in older individuals, related to age but not to sex.
Associations
Focal ...
Article
Facet joint injection
Facet (zygapophyseal) joint injections are performed primarily for the diagnosis and differentiation of facet syndrome and radicular pain syndrome, and are one of the spinal interventional procedures. They can be performed under fluoroscopic, or CT image guidance, and cervical, thoracic or most ...
Article
Meningocele
Meningoceles (also spelled meningocoele) 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 surger...
Article
Cervical rib
Cervical ribs are supernumerary or accessory ribs arising from the seventh cervical vertebra. They occur in ~0.5% of the population, are usually bilateral, but often asymmetric 2, and are more common in females.
Related pathology
Although cervical ribs are usually asymptomatic, they are the mo...
Article
Intradural spinal lipoma
Intradural lipomas are a subset of spinal lipomas. They are typically intradural, subpial, juxtamedullary lesions 1 although they have occasionally been reported as entirely intramedullary lesions 2.
Mature fatty tissue within the spinal dura can be seen in a number of entities:
lipomyelo...
Article
Extrapulmonary tuberculosis
Extrapulmonary tuberculosis (TB) refers to the hematogenous spread of Mycobacterium tuberculosis.
Pathology
Extrapulmonary tuberculosis can occur as a primary form of the disease, i.e. direct infection of an extrapulmonary organ without the presence of primary pulmonary tuberculosis or it can ...
Article
Harris ring
A Harris ring is a ring-like shadow observed at the base of the odontoid process on a lateral radiograph of the cervical spine. It is formed by the superimposition of the lateral masses of the C2 vertebra (axis) on its body.
Disruption of the Harris ring is seen in type III, and less commonly, ...
Article
Notochord
The notochord represents the earliest fetal axial skeleton, extending from the Rathke pouch to the coccyx. It is a primitive cell line from which the skull base and vertebral column develop. The notochord is cylindrical and is replaced by sclerotomes that produce cartilage, and subsequently bone...
Article
Intercalary bone
Intercalary bones are common discal ossifications that are usually triangular in morphology, found in the anterior annular fibers of an intervertebral disc, and are thought to be degenerative in etiology.
Differential diagnosis
limbus vertebra
flexion or extension teardrop fracture
Article
H-shaped vertebra
H-shaped vertebrae, also known as Lincoln log vertebrae, are a characteristic finding of sharply delimited central endplate depression, classically seen in approximately 10% of patients with sickle cell disease, and results from microvascular endplate infarction (Figure 1) 3.
It may occasionall...
Article
Facet joint tropism
Facet joint tropism refers to a situation where there is a difference in the orientation/angle of facet joints (i.e. between the left and right sides) with respect to each other in the sagittal plane. This can lead to unequal biomechanical forces on the facet joints and intervertebral disc durin...
Article
Suboccipital muscle group
The suboccipital muscle group contains four paired muscles, three of which pairs belong to the suboccipital triangle. These muscles all lie below the occipital bone and are responsible for postural support of the head, as well as extension, lateral flexion and rotation. As these muscles are smal...
Article
Whiplash syndrome
Whiplash syndrome, also known as whiplash-associated disorders (WAD), are the various symptoms caused by rapid acceleration and/or deceleration injuries, which result in cervical sprain or strain.
Epidemiology
Whiplash is a common injury, usually associated with motor vehicle collisions 1-5. T...
Article
Fifth lumbar vertebra (L5)
The fifth lumbar vertebra (L5) is the largest of the five lumbar vertebrae and is considered an atypical vertebra due to its shape.
Gross anatomy
L5 is the largest, most inferior lumbar discovertebral unit in the vertebral column, and participates in forming the lumbar lordosis (from L1 to L5...
Article
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.
Radiographic features
MRI
T1-weighted imaging without fat suppression is one of the most important sequences for distinguishing between normal and abnormal bone marrow. Ab...
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