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 continuously improved upon by countless contributing members. Our dedicated editors oversee each edit for accuracy and style. Find out more about articles.
174 results found
Article
Alar ligament
The alar ligaments join the lateral margins of the sloping upper posterior margin of the dens of C2 to the lateral margins of the foramen magnum (adjacent to the occipital condyles) and lie on either side of the apical ligament. They may be oblique or vertical and are thickest at the occipital a...
Article
Vertebral body endplate
Vertebral body endplates are anatomically discrete structures that form the interface between the vertebral bodies and the adjacent intervertebral discs. They are constituted centrally by a cartilaginous layer and peripherally by a bone ring apophysis. The cartilaginous layer is related to the n...
Article
Anterior corticospinal tract
The anterior corticospinal tract is formed at the level of the of the medullary pyramids, where the majority (90%) of descending corticospinal tract fibers decussate to form the lateral corticospinal tract. The remaining non-decussating fibers (10%) form the much smaller anterior corticospinal t...
Article
Arterial vasocorona
The arterial vasocorona is part of the spinal cord blood supply and is formed by pial anastomoses between the anterior and posterior spinal arteries on the surface of the spinal cord. It encircles the cord and supplies the peripheral lateral aspect of the spinal cord.
Engorgement of arterial v...
Article
Annulus fibrosus
The annulus fibrosus (plural: annuli fibrosi) surrounds the nucleus pulposus and together they form the intervertebral disc.
Gross anatomy
The annulus comprises 15 to 20 collagenous (type I) laminae which run obliquely from the edge of one vertebra down to the edge of the vertebra below. The d...
Article
Ligamentum nuchae
The ligamentum nuchae or nuchal ligament is a large median ligament composed of tendons and fascia located between the posterior muscles of the neck.
Gross anatomy
The ligament nuchae covers the spines of C1 to C6 vertebrae. It is a superior and posterior extension of the supraspinous ligament...
Article
Paracondylar process
The paracondylar process, also known as the paraoccipital, paramastoid, parajugular or estiloid process, is a rare anatomical variant of the occipital where a bony exostosis extends caudally from the paracondylar region (lateral to the native occipital condyles), typically articulating with the ...
Article
Autonomic nervous system
The autonomic nervous system (ANS) is a subdivision of the peripheral nervous system. The autonomic system provides innervation of the involuntary muscles, i.e. myocardium and smooth muscle, and glands, through which fine control of homeostasis is maintained.
The afferent innervation of the aut...
Article
Parasympathetic nervous system
The parasympathetic nervous system (PaNS/PNS), mediated by the head and neck ganglia and pelvic splanchnic nerves, is a major division of the autonomic nervous system. It is composed of general visceral afferent and efferent axons that allow for involuntary control of bodily functions via severa...
Article
Sympathetic nervous system
The sympathetic nervous system (SNS), mediated by the sympathetic chain (trunk) and ganglia, is a major division of the autonomic nervous system. It is composed of general visceral afferent and efferent axons that allow for involuntary control of bodily functions via the hypothalamus.
The over...
Article
Butterfly vertebra
Butterfly vertebra, also sometimes known as a sagittal cleft vertebra or anterior rachischisis, is a type of vertebral anomaly that results from the failure of fusion of the lateral halves of the vertebral body because of persistent notochordal tissue between them.
Pathology
Butterfly vertebra...
Article
Occipital vertebra
Occipital vertebrae are rare anatomical variants that result from incomplete or aberrant fusion of occipital bone ossification centers. There is a broad spectrum of occipital vertebrae, the more common variants include:
third condyle (condylus tertius)
basilar process
prebasioccipital arch
p...
Article
Basilar process
The basilar process, also known as the mammillar or papillar process, is a rare anatomical variant of the occipital bone that is part of the spectrum of occipital vertebrae 1.
Epidemiology
The basilar process is a rare variant, with a reported prevalence of 4% 2.
Clinical presentation
A basi...
Article
Conus medullaris
The conus medullaris is the tapered inferior-most part of the spinal cord to which is attached the filum terminale.
Gross anatomy
The conus medullaris is conical in shape, tapering from the distal spinal cord to a narrow point from which a delicate strand of fibrous tissue called the filum ter...
Article
Spinal cord
The spinal cord is the part of the central nervous system found within the vertebral column's spinal canal. The cord extends from the corticomedullary junction at the foramen magnum of the skull down to the tip of the conus medullaris within the lumbar cistern. It is lined by the spinal pia mate...
Article
Iliolumbar ligament
The iliolumbar ligament is a strong band of connective tissue which courses from the transverse process of L5 (in over 96% of cases) to the posterior iliac wing and crest of the ilium. It functions to maintain the alignment of L5 on the sacrum during various movements 1,2.
It is an important la...
Article
Labeled imaging anatomy cases
This article lists a series of labeled imaging anatomy cases by body region and modality.
Brain
CT head: non-contrast axial
CT head: non-contrast coronal
CT head: non-contrast sagittal
CT head: non-contrast axial with clinical questions
CT head: angiogram axial
CT head: angiogram coronal
...
Article
Congenital anomalies of the posterior atlas arch
Congenital anomalies of the posterior arch of the atlas (C1) are relatively common anomalies. They may range from partial defects presenting as clefts to complete absence of the posterior arch (aplasia).
These anomalies are classified according to Currarino (see below). It should not be confuse...
Article
Conjoined nerve root
Conjoined nerve roots are the most common nerve root developmental anomaly of the cauda equina, being twice as common as two roots in the same foramen, the next most common anomaly.
Epidemiology
The incidence in cadaveric studies is ~10% (range 8-14%) 2, and in one prospective MRI study was 6%...
Article
Vertebra
The vertebra (plural: vertebrae) is the fundamental segmental unit of the vertebral column (also known as the spine).
Gross anatomy
Vertebrae, apart from those that are atypical, have a similar basic structure which can be described as an anterior vertebral body and a posterior neural (or vert...
Unable to process the form. Check for errors and try again.