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.
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Article
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...
Article
Cervical spine (lateral view)
Cervical spine lateral view is a lateral projection of the cervical spine. It is often performed in the setting of trauma.
As technology advances, computed tomography (CT) has replaced this projection, yet there remain many institutions (especially in rural areas) where CT is not readily availa...
Article
Cervical spine ligaments
Cervical spine ligaments ordered from anterior to posterior include:
anterior longitudinal ligament (ALL)
anterior atlanto-occipital membrane
apical ligament
alar ligaments (paired)
cruciate ligament of the atlas
longitudinal band: joins the body of the axis to the foramen magnum
transver...
Article
Cervical spine (odontoid view)
The odontoid or 'peg' projection is an AP projection of C1 (atlas) and C2 (axis).
Patient position
patient positioned erect in AP position unless trauma the patient will be supine
patient’s shoulders should be at equal distances from the image receptor to avoid rotation, the head facing strai...
Article
Chalk stick fracture
Chalk stick or carrot stick fractures are fractures of the fused spine, classically seen in ankylosing spondylitis.
Terminology
Some authors define the chalk stick fracture as a fracture through a Pagetoid long bone (see Paget disease).
Pathology
They usually occur through the disco-vertebra...
Article
Chamberlain line
Chamberlain line is a line joining the back of hard palate with the opisthion on a lateral view of the craniocervical junction.
Significance
It helps to recognise basilar invagination which is said to be present if the tip of the dens is >3 mm above this line.
McGregor developed a modificatio...
Article
Chance fracture
Chance fractures, also referred to as seatbelt fractures, are flexion-distraction type injuries of the spine that extend to involve all three spinal columns. These are unstable injuries and have a high association with intra-abdominal injuries.
Pathology
Mechanism
They tend to occur from a fl...
Article
Charcot-Marie-Tooth disease
Charcot-Marie-Tooth (CMT) disease, also known as hereditary motor and sensory neuropathy (HMSN), is the most commonly inherited neuropathy of lower motor (to a lesser degree sensory) neurons.
Clinical presentation
Signs and symptoms usually become first evident in childhood. Typically this sta...
Article
Chest x-ray: disability (summary)
This is a basic article for medical students and other non-radiologists
Chest x-ray review is a key competency for medical students, junior doctors and other allied health professionals. Using A, B, C, D, E is a helpful and systematic method for chest x-ray review where D refers to disability a...
Article
Clasp-knife deformity
Clasp-knife deformity is relatively common congenital anomaly found at the lumbosacral junction.
Terminology
When a clasp-knife deformity is accompanied by pain on extension secondary to protrusion of the enlarged spinous process (knife blade) into the sacral spinal canal, it is called clasp-k...
Article
Classification of spinal meningeal cysts
Spinal meningeal cysts can be classified according to a system published by Nabor et. al 2:
type I: extradural meningeal cyst without neural tissue
type Ia: extradural spinal arachnoid cyst
type Ib: sacral meningocele
type II: extradural meningeal cyst containing neural tissue, e.g. Tarlov c...
Article
Clay-shoveler fracture
Clay-shoveler fractures are fractures of the spinous process of a lower cervical vertebra.
Clinical presentation
Often these injuries are unrecognised at the time and only found incidentally years later when the cervical spine is imaged for other reasons.
Acutely they tend to be associated wi...
Article
Cobb angle
The Cobb angle is the most widely used measurement to quantify the magnitude of spinal deformities, especially in the case of scoliosis, on plain radiographs. A scoliosis is defined as a lateral spinal curvature with a Cobb angle of 10° or more 4.
Measurement
To measure the Cobb angle, one mus...
Article
Coccidioidomycosis
Coccidioidomycosis refers to an infection caused by the dimorphic fungus Coccidioides spp, usually localised to the lungs. This disease is not to be confused with the similarly named paracoccidioidomycosis.
Epidemiology
The most common forms of Coccidioides spp are Coccidioides immitis and Coc...
Article
Coccyx
The coccyx is the series of rudimentary vertebrae forming the caudal termination of the vertebral column and is positioned inferior to the apex of the sacrum. The coccyx is one leg of the tripod formed in conjunction with the ischial tuberosities for support in a seated position. Additionally, i...
Article
Column of Burdach
The column of Burdach, also known as the cuneate fasciculus or fasciculus cuneate, represents the lateral portion of the dorsal columns and carries input from between and including C1 and T6 1.
Function
The cuneate fasciculus is responsible for transmitting vibration, conscious proprioception...
Article
Column of Goll
The column of Goll, also known as the gracile fasciculus or fasciculus gracilis, represents the medial portion of the dorsal columns and carries input from below and including T7 1.
Function
The gracile fasciculus is responsible for transmitting vibration, conscious proprioception, and fine (d...
Article
Congenital absence of a spine pedicle
Congenital absence of a spine pedicle is a rare congenital condition, but awareness of its characteristic imaging appearance is important to avoid misdiagnosis.
Failure to recognise this entity can lead to misdiagnosis of unilateral facet subluxation/dislocation, leading to unnecessary treatmen...
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
Congenital lumbar spinal stenosis
Congenital lumbar spinal stenosis (CLSS) is a type of spinal canal stenosis and has a different epidemiology with less severe degenerative change compared to acquired/degenerative lumbar spinal stenosis.
Epidemiology
CLSS tends to affect patients at a younger age (30-50 years old) than lumbar...
Article
Conus medullaris
The conus medullaris is the terminal end of the spinal cord.
Gross anatomy
After the cord terminates, the nerve roots descend within the spinal canal as individual rootlets, collectively termed the cauda equina. The conus medullaris most commonly terminates at the L1/2 intervertebral disc leve...
Article
Conus medullaris syndrome
Conus medullaris syndrome is caused by an injury or insult to the conus medullaris and lumbar nerve roots. It is a clinical subset of spinal cord injury syndromes. Injuries at the level of T12 to L2 vertebrae are most likely to result in conus medullaris syndrome.
Pathology
The conus medullari...
Article
Corduroy sign (vertebral haemangioma)
The corduroy sign refers to vertically-oriented, thickened trabeculae seen in intraosseous haemangiomas of the spine. It is the sagittal/coronal equivalent of the polka-dot sign seen on axial imaging.
It is caused by the replacement of the normal cancellous bone by thickened vertical trabecula...
Article
Coronal balance
Coronal balance is one of the features that needs to be assessed on long spine radiographs obtained for spinal deformity, particularly scoliosis. It measures whether or not the upper spine is located over the midline (normal) or off to one side.
To assess coronal balance, a vertical (plumb) li...
Article
Coronal vertebral cleft
Coronal vertebral cleft refers to the presence of a radiolucent vertical defect 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) ...
Article
Corpectomy
Corpectomy refers to removal of one or more vertebral bodies to treat compressive myelopathy caused by extensive hypertrophic osteoarthritis. In most cases, the intervertebral discs are removed as well. It is most commonly performed for degenerative cervical myelopathy; however, thoracic and lum...
Article
Cortical bone
The outer shell of compact bone is called cortical bone or cortex.
Gross anatomy
Cortical bone contains Haversian systems (osteons) which contain a central Haversian canal surrounded by osseous tissue in a concentric lamellar pattern.
Two fibrovascular layers surround the cortical bone which...
Article
Corticorubral tract
The corticorubral tract contains neurons that connect the primary motor and sensory areas to the red nucleus. The rubrospinal tract then descends through the spinal cord.
The tract is thought to excite flexor muscles and inhibit extensor muscles.
Gross anatomy
Central connections
The corti...
Article
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 cranio-vertebral junctio...
Article
Crowned dens syndrome
The crowned dens syndrome is an inflammatory condition resulting from crystal deposition in cruciform and alar ligaments surrounding the dens, appearing as a radiopaque 'crown' surrounding the top of the dens. It typically presents with pain and increased inflammatory markers.
Terminology
Th...
Article
Cruciate ligament of the atlas
The cruciate ligament of the atlas (also known as the cruciform ligament) is an important ligamentous complex that holds the posterior dens of C2 in articulation at the median atlantoaxial joint. It lies behind a large synovial bursa (surrounded by loose fibrous capsule) and consists of two band...
Article
Curtain sign
The curtain sign (or draped curtain sign) in neuroimaging refers to the appearance of a vertebral body mass that extends to the anterior epidural space.
The posterior longitudinal ligament is strongly attached to the posterior vertebral body cortex in the midline and is more loosely attached la...
Article
Cyst of the medullary conus
Cyst of the medullary conus is a rare benign ependymal cyst of the conus medullaris which probably relates to abnormal persistence and cystic dilatation of the ventriculus terminalis or "5th ventricle". This entity can be symptomatic and present in adulthood with bladder or bowel sphincter distu...
Article
Dagger sign (spine)
The dagger sign is a radiographic feature seen in ankylosing spondylitis as a single central radiodense line on frontal radiographs related to ossification of the supraspinous and interspinous ligaments.
Article
Degenerative disc disease
Degenerative disc disease (DDD) is an exceedingly common entity in the spine, encountered with increasing frequency throughout life and becoming almost universal in late adulthood to a varying degree. It is related to a combination biomechanical stresses and genetic predisposition which alter th...
Article
Déjerine-Sottas disease
Déjerine-Sottas disease, also known as hereditary motor and sensory neuropathy type III or hypertrophic interstitial polyneuritis, is a rare hereditary motor and sensory neuropathy (HMSN).
This syndrome should not be confused with Déjerine syndrome or Déjerine-Roussy syndrome.
Clinical present...
Article
Denticulate ligaments
The denticulate ligaments are bilateral triangular lateral extensions of pia mater that anchor the spinal cord to the dura mater.
They are formed by pia mater of the spinal cord coursing in-between the dorsal and ventral nerve roots bilaterally. They function to provide stability to the spinal ...
Article
Denver criteria for blunt cerebrovascular injury
The Denver criteria are a set of screening criteria for blunt cerebrovascular injury (BCVI) in trauma used to reduce the need for CT angiography and its associated radiation exposure.
Screening criteria
The screening protocol criteria 1,3 for BCVI are divided into signs and symptoms of BCVI a...
Article
Diastematomyelia
Diastematomyelia, also known as a split cord malformation, refers to a type of spinal dysraphism (spina bifida occulta) when there is a longitudinal split in the spinal cord.
Terminology
Although traditionally it has been distinguished from diplomyelia (in which the cord is duplicated rather ...
Article
Difference in vertical mid-vertical angle (lumbar spine)
The difference in vertical mid-vertical angle is the difference in the vertical mid-vertebral angle (VMVA) between the caudal segment angle and the adjacent cephalad segment angle of the three most caudal segments of the lumbar spine as measured on a mid-sagittal MRI or a lateral radiograph.
Ra...
Article
Diffuse idiopathic skeletal hyperostosis
Diffuse idiopathic skeletal hyperostosis (DISH), also referred to as Forestier disease, is a common condition characterised by bony proliferation at sites of tendinous and ligamentous insertion of the spine affecting elderly individuals.
On imaging, it is typically characterised by the flowing ...
Article
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...
Article
Diffuse T1 bone marrow signal loss
Diffuse T1 vertebral bone marrow signal loss has a number of causes. T1-weighted imaging without fat suppression is one of the most important sequences for distinguishing between normal and abnormal bone marrow. Given the homogeneity, this appearance can often be difficult to spot as abnormal. ...
Article
Diplomyelia
Diplomyelia is a rare spinal cord malformation in which the cord is duplicated. It should be distinguished from diastematomyelia in which a single cord is split. Having said that it has been proposed that the term be abandoned in favour of split cord malformation, which encompasses both diastema...
Article
Discal cyst
Discal cysts (also known as a disk cyst or disc cyst) are uncommon lesions of the spine, representing an extrathecal cyst which communicates with the adjacent intervertebral disc through an annular fissure.
Epidemiology
The vast majority of discal cysts, as rare as they are, have been reporte...
Article
Disc bulge
A disc bulge represents displacement of the outer fibres of the annulus fibrosus beyond the margins of the adjacent vertebral bodies, involving more than one quarter (25%, 90 degrees) of the circumference of an intervertebral disc 3. Because it is limited by the annulus fibrosus it does not ext...
Article
Disc desiccation
Disc desiccation is an extremely common degenerative change of intervertebral discs. The incidence climbs with age, and to a large degree a gradual desiccation is a 'normal' part of disc aging. It results from replacement of the hydrophilic glycosaminoglycans within the nucleus polposus with fib...
Article
Disc extrusion
Disc extrusion is a type of intervertebral disc herniation and is distinguished from a disc protrusion in that it:
in at least one plane, has a broader dome (B) than a neck (A)
and/or
extends above or below the disc level (into the suprapedicular or infrapedicular zone)
Disc extrusions are a...
Article
Disc herniation
Disc herniation refers to the displacement of intervertebral disc material beyond the normal confines of the disc but involving less than 25% of the circumference (to distinguish it from a disc bulge. A herniation may contain nucleus pulposus, vertebral endplate cartilage, apophyseal bone/osteop...
Article
Disc osteophyte complex
Disc osteophyte complex is a term used on MRI of the cervical spine to denote the presence of disc protrusion and/or marginal endplate osteophytes resulting in narrowing of the cervical canal. The term was introduced early in the practice of MRI as distinguishing between disc and osteophyte can ...
Article
Disc protrusion
Disc protrusions are a type of disc herniation characterised by protrusion of disc content beyond the normal confines of the intervertebral disc, over an segment less than 25% of the circumference of the disc. The width of the base is wider than the largest diameter of the disc material which pr...
Article
Disc sequestration
Sequestrated disc, also referred to as a free disc fragment, corresponds to extruded disc material that has no continuity with the parent disc and is displaced away from the site of extrusion. By definition, it corresponds to a subtype of disc extrusion.
The term "migrated" disc refers only to ...
Article
Dorsal columns
The dorsal columns, or posterior columns, are ascending pathways primarily concerned with sensory function. They are responsible for transmitting vibration, conscious proprioception, and fine (discriminative) touch 1,2.
The dorsal columns are divided two tracts, which are discussed separately 2...
Article
Dorsal dermal sinus
Dorsal dermal sinus (DDS) is an epithelium-lined tract from the skin to the spinal cord, cauda equina, or arachnoid.
Pathology
Dorsal dermal sinus is caused by incomplete separation of the superficial ectoderm from the neural ectoderm, resulting in a focal segmental adhesion.
Later during emb...
Article
Dorsal epidural disc migration
Dorsal epidural disc migration represents, as the name suggests, migration of disc material, usually a sequestrated disc fragment, into the dorsal (posterior) epidural space, posterior to the theca. This is a rare occurrence, often not suspected preoperatively and is almost invariably encountere...
Article
Dorsal root ganglion
The dorsal root ganglia are an enlargement of the dorsal root of spinal nerves representing the cell bodies of the primary somatosensory neurons.
Gross anatomy
Each dorsal root ganglion is oval and proportional in size to its related root. They are usually found just distal to the intervertebr...
Article
Dorsal thoracic arachnoid web
Dorsal thoracic arachnoid web refers to a thickened band of arachnoid over the dorsal aspect of the cord. It usually causes a focal thoracic cord distortion with consequent neurological dysfunction.
On imaging, it is characterised by a focal dorsal indentation and anterior displacement of the ...
Article
Dumbbell appearance of spinal tumours
The dumbbell appearance of spinal tumours refers to a tumour which has both a component within the canal and a component in the paravertebral space contiguous with each other via a thinner tumour component traversing the neural exit foramen.
The appearance can be seen in:
spinal nerve sheath t...
Article
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...
Article
Empty thecal sac sign
The empty thecal sac sign or empty sac sign is when the thecal sac appears empty on MRI of the lumbar spine, best seen on T2-weighted images. If the empty thecal sac sign is present, a diagnosis of adhesive arachnoiditis can be made.
Radiographic features
MRI
There is usually no gadolinium c...
Article
Ependymoma vs astrocytoma of the spinal cord
A number of factors are useful when differentiating between spinal cord ependymoma and spinal cord astrocytoma.
Ependymoma
child or adult
more central in location
bone remodelling is common
low T1 signal
well-defined enhancement
syrinx is more common
haemorrhage is more common
Astrocyt...
Article
Epidural angiolipoma
Epidural angiolipomas are rare benign tumours composed of mature adipocytes and abnormal vessels.
Epidemiology
Epidural angiolipomas are more frequently encountered in women, and typically in middle age (40-50 years of age) 1.
Clinical presentation
In keeping with the slow growth of these ...
Article
Epidural blood patch
Epidural blood patch is a treatment option for patients with craniospinal hypotension or post lumbar puncture headaches. The procedure can be done blind or under fluoroscopic or CT guidance, and is performed predominantly by radiologists and anaesthetists.
Indications
craniospinal hypotension...
Article
Epidural lipomatosis
Epidural lipomatosis refers to an excessive accumulation of fat within the spinal epidural space, typically in the lumbar region, such that the thecal sac is compressed, and in some instances results in compressive symptoms.
Epidemiology
Demographic of affected individuals reflects the underl...
Article
Epitransverse process of the atlas
Epitransverse process is a rare anatomical variant of the atlas, consisting of a bony exostosis which extends cephalad from from the transverse process of the atlas to articulate with the occipital bone. This process sometimes meets with a paracondylar process, forming a pseudoarthrosis at the i...
Article
Erector spinae group
The erector spinae group is the intermediate layer of the intrinsic muscles of the back. This group is made of three subgroups, with the group divisions occurring by location. The iliocostalis group occurs most laterally, followed by the longissimus group, and finally the spinalis as the most me...
Article
Erector spinae muscles (mnemonic)
There are multiple handy mnemonics to recall the erector spinae muscles. They usually describe the position from lateral to medial.
I Like Standing
I Love Sex
I Long for Spinach
I Like Siri
Mnemonic
I: iliocostalis
L: longissimus
S: spinalis
Article
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...
Article
Extension tear drop fracture
Extension tear drop fracture typically occurs due to forced extension of the neck with resulting avulsion of the anteroinferior corner of the vertebral body. Extension teardrop fractures are stable in flexion, and unstable in extension as the anterior longitudinal ligament is disrupted. Extensio...
Article
Extrapulmonary tuberculosis
Extrapulmonary tuberculosis (TB) refers to the haematogenous spread of Mycobacterium tuberculosis.
Pathology
Extrapulmonary tubercuosis 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
Facet dislocation
Facet dislocation refers to anterior displacement of one vertebral body on another. Without a fracture, the only way anterior displacement can occur is by dislocation of the facets.
Facet dislocation can occur to varying degrees:
subluxed facets
perched facets
locked facets
The injury usua...
Article
Facet joint
The facet (or apophyseal or zygapophyseal) joints are the articulations of the posterior arch of the vertebrae and form part of the posterior column.
Gross anatomy
They are symmetrical synovial-lined joints that have a fibrous capsule and connect the articular facets of the vertebrae. The sup...
Article
Facet joint capsule
Facet joint capsules are the fibrous capsule that surround the vertebral facet or zygapophyseal joints. They are particularly thin and loose, attached to the margins of articular facets on adjoining articular processes. The capsules merge medially with the ligamentum flavum.
In the cervical re...
Article
Failed back syndrome
Failed back syndrome refers to persistent leg and/or lumbar back pain after a surgical procedure. The pathophysiology of this syndrome is complex, as often the operation was technically successful.
Terminology
Other names for failed back syndrome include failed back surgery syndrome, post-lam...
Article
Fibrocartilaginous embolism
Fibrocartilaginous embolism (also known as nucleus pulposus embolism) is a rare cause of spinal cord ischaemia due to embolisation of nucleus pulposus material from intervertebral disc in a retrograde direction into a spinal artery or vein.
Fibrocartilaginous embolism is a diagnosis of suspicio...
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
Filum terminale
The filum terminale is a filament of connective tissue that extends inferiorly from the apex of the conus medullaris.
Gross anatomy
The filum terminale is continuous with the pia mater and is described as having two sections:
filum terminale internum: upper three quarters of the filum; covere...
Article
Fish vertebra
Fish vertebra, also known as codfish vertebra, describes the biconcave appearance of vertebrae (especially lumbar vertebrae).
Pathology
Seen in:
osteoporosis
sickle cell disease
hereditary spherocytosis
homocystinuria
renal osteodystrophy
osteogenesis imperfecta
thalassemia major (rare...
Article
Flexion tear drop fracture
Flexion tear drop fractures are the most severe fracture of the cervical spine, often causing anterior cervical cord syndrome and quadriplegia.
Pathology
Mechanism
It typically occurs from severe flexion and compression forces, most commonly at C5-6 (e.g. diving head first, motor vehicle coll...
Article
Fluid sign (vertebral collapse)
The fluid sign is one of the radiological features of osteoporotic fractures, and can be helpful in distinguishing them from metastatic vertebral fractures, as it is seen more often in osteoporotic fractures and is rarely seen in metastatic fractures 1. It is not as helpful as identifying a para...
Article
Fluoroscopy guided lumbar puncture
Fluoroscopy-guided lumbar puncture (LP) is a minimally invasive, image-guided diagnostic and therapeutic procedure that involves the removal of a small volume of cerebrospinal fluid (CSF) from, or an injection of medication or other substance (e.g. radiotracer, chemotherapy agents) into the lumb...
Article
Fluorosis
Skeletal fluorosis is a chronic metabolic bone disease caused by ingestion of large amounts of fluoride through either water or food in geographic areas where high levels of fluoride occur naturally.
Radiographic features
Plain film/CT
Described features include:
increased bone density: oste...
Article
Focal fatty deposits in spinal bone marrow
Focal fatty deposits/replacement in spinal bone marrow are well-defined focal fat islands within the bone marrow of spine or other parts of axial skeleton.
Epidemiology
Common in older individuals, related to age and not related to sex.
Pathology
This process is a normal variant. Histologica...
Article
Foix-Alajouanine syndrome
Foix-Alajouanine syndrome refers to presentation of spinal AVMs with progressive neurological deterioration.
Initially, patients have a spastic paraplegia which progresses to flaccidity, loss of sphincter control and ascending sensory level. It is thought to be due to venous hypertension.
Article
Foraminal disc protrusion
Foraminal disc protrusion (see intervertebral disc disease nomenclature) is an important entity to recognise for a number of reasons.
First of all it is relatively easy to overlook as it does not impinge upon the spinal canal. Secondly as it does not narrow the subarticular recess it compresses...
Article
Friedreich ataxia
Friedreich ataxia (FA) is the most common inherited progressive ataxia. It carries an autosomal recessive inheritance 1.
Epidemiology
Thought to have an estimated prevalence of ~1:50,000. There is no recognised gender predilection.
Typically present in childhood to adolescence. Those with a h...
Article
Ganglioneuroma
Ganglioneuromas are fully differentiated neuronal tumours that do not contain immature elements and potentially occur anywhere along the peripheral autonomic ganglion sites.
On imaging, usually, they present as well-defined solid masses and can be quite large at presentation. Generally, they a...
Article
Genant classification of vertebral fractures
The Genant classification of vertebral fractures is based on the vertebral shape, with respect to vertebral height loss involving the anterior, posterior, and/or middle vertebral body.
grade 0: normal
grade 1: mild fracture, 20% to 25% loss of height
grade 2: moderate fracture, 25% to 40% los...
Article
Ghost vertebra
Ghost vertebra is a sign, that is generally used synonymously with bone-within-a-bone vertebra, and as such, the causes form a subset of those causing bone within a bone appearance 2:
Thorotrast administration: bone within a bone appearance due to temporary growth arrest 1
stress line
rickets...
Article
Gibbus deformity
Gibbus deformity is a short-segment structural thoracolumbar kyphosis resulting in sharp angulation.
Pathology
There are a number of causes which can be divided into congenital and acquired.
Congenital
achondroplasia
cretinism (congenital hypothyroidism)
Apert syndrome
Coffin-Lowry syndro...
Article
Ginkgo leaf sign (spinal meningioma)
The ginkgo leaf sign of spinal meningiomas (not to be confused with the ginkgo leaf sign of subcutaneous emphysema) has been described as a useful MRI sign in distinguishing a spinal meningioma from neurogenic tumour (e.g. spinal schwannoma).
It is seen on axial post contrast T1 imaging, with ...
Article
Grisel syndrome
Grisel syndrome is a rare cause of torticollis that involves subluxation of atlanto-axial joint from inflammatory ligamentous laxity following an infectious process in the head and neck, usually a retropharyngeal abscess.
Epidemiology
It usually occurs in infants or young children.
Clinical p...
Article
Guillain-Barré syndrome
Guillain-Barré syndrome (GBS) is defined as a heterogeneous group of autoimmune polyradiculopathies, involving sensory, motor and autonomic nerves. It is the most common cause of rapidly progressive flaccid paralysis. It is believed to be one of a number of related conditions, sharing a similar ...