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Spinal schwannoma

Spinal schwannomas are benign nerve sheath tumors within the spinal canal, typically arising from spinal nerve roots and it is the most common nerve sheath tumor of spine 11. They are one of the two most common intradural extramedullary spinal tumors, representing 15-50% of such lesions. This a...

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...

Neoplasms of the spinal canal

Neoplasms of the spinal canal encompass a range of tumors which arise from or involve the spinal cord, theca, and spinal nerves. Pathology These can be divided according to the tissue/structure of origin within the spinal canal. Tumors of vertebral bodies are discussed separately: see vertebra...

Ossification of the posterior longitudinal ligament

Ossification of the posterior longitudinal ligament (OPLL) is typically an entity seen in patients of Asian descent, although it is seen in all ethnic groups. It is characterized by, as the name suggests, ossification of the posterior longitudinal ligament. Epidemiology There is a recognized g...

Inverted Napoleon hat sign

The inverted Napoleon hat sign is a radiologic sign seen on the frontal pelvic or lumbar radiograph at the level of the 5th lumbar vertebra and the sacrum. It is seen when there is bilateral spondylolysis with marked anterolisthesis of L5 on S1 or marked exaggeration of the normal lordosis at t...

Lipoma of the filum terminale

Lipoma of the filum terminale, also known as fatty filum terminale or filar lipoma, is a relatively common finding on imaging of the lumbar spine, and in most cases is an incidental finding of no clinical concern. However, in some patients it may be associated with signs and symptoms of tethered...

WHO classification of CNS tumors

The WHO classification of CNS tumors is the most widely accepted system for classifying CNS tumors, now into its 5th edition, traditionally published in a blue cover (thus "blue book"). Although traditionally based on histological characteristics of the tumors, since the 2016 revised 4th editio...

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...

Vertebral body squaring (differential)

Vertebral body squaring refers to the loss of normal concavity of the anterior border of the vertebral body. It is seen in a variety of conditions, some of which are listed below. Differential diagnosis Ankylosing spondylitis Ankylosing spondylitis is the most common cause of vertebral body ...

Vertebral anomalies

The vertebral column is affected by a range of anatomical variants of the body and/or neural arch as well as accessory ossicles. Knowledge of basic vertebral anatomy and ossification is essential for describing and understanding the range of anomalies. Variant anatomy Vertebral body hemiverte...

Unfused spinous process

Unfused spinous process, which is really failure of fusion of the neural arch, is a relatively common anatomical variant and is part of the spectrum of spina bifida occulta. This should be differentiated from accessory ossicles of the spinous process, which appear after non-fusion of the secon...

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...

Tuberculosis

Tuberculosis (commonly abbreviated to TB, short for tubercle bacillus) encompasses an enormously wide disease spectrum affecting multiple organs and body systems predominantly caused by the organism Mycobacterium tuberculosis. A small proportion can also be caused by Mycobacterium bovis. Epide...

Transforaminal epidural steroid injection

Transforaminal epidural steroid injections (TFESI), also known as transforaminal nerve root injections or nerve root blocks, are performed for the treatment and diagnosis of radicular pain. They differ from selective nerve root blocks (SNRB), as the aim is to get an "epidural spill" and get the ...

Toothpaste sign

The toothpaste sign in spinal imaging represents an extrusion of an intervertebral disc into the epidural space. It is called after the shape of extruded material relatively to the parent disc in a sagittal plane.

Sugar coating

So-called "sugar coating" or zuckerguss (German for sugar icing) refers to the appearance of diffuse linear/sheetlike leptomeningeal contrast enhancement in the brain or spinal cord due to drop metastases or leptomeningeal carcinomatosis. It is seen both as a result of CNS involvement from dista...

Subacute combined degeneration of the cord

Subacute combined degeneration of the cord is caused by vitamin B12 deficiency. Epidemiology Most common in patients older than 40 years and especially older than 60 years 7. Clinical presentation The clinical presentation of subacute combined degeneration is usually with loss of vibration ...

Straight back syndrome

Straight back syndrome refers to decreased thoracic kyphosis ("flattening") and decreased anteroposterior thoracic diameter, such that there is compression of cardiovascular or bronchial structures. It should not be confused with flat back syndrome, which refers to decreased lumbar lordosis, o...

Spondylolisthesis grading system

A commonly adopted method of grading the severity of spondylolisthesis is the Meyerding classification. It divides the superior endplate of the vertebra below into 4 quarters. The grade depends on the location of the posteroinferior corner of the vertebra above. This classification was original...

Spinal interventional procedures

Back pain is a common condition that is often difficult to treat. Lumbar degenerative facet joints, lumbar disc disease and sacroiliac joint pain account for nearly 70% of cases of lower back pain. Unfortunately, as the incidence of degenerative changes in the spine is so high (e.g. disc abnorm...

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 extramedullary hematopoiesis spinal ...

Spinal epidural injection

Epidural spinal injections are one of the more frequently performed spinal interventional procedures. Three approaches to the epidural space exist: caudal epidural injection (via the sacral hiatus) interlaminar epidural injection cervical interlaminar epidural injection lumbar interlaminar ...

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 teardrop...

Shiny corner sign (ankylosing spondylitis)

The shiny corner sign is a spinal finding in ankylosing spondylitis, representing reactive sclerosis secondary to inflammatory erosions at the superior and inferior endplates (corners on lateral radiograph) of the vertebral bodies which are known as Romanus lesions. Eventually, the vertebral bod...

Scoliosis

Scoliosis (plural: scolioses) is defined as an abnormal lateral curvature of the spine. It is quite common in young individuals and is often idiopathic and asymptomatic. In some cases, however, it is the result of underlying structural or neurological abnormalities. Terminology Early onset sco...

Schmorl nodes

Schmorl nodes, also known as intravertebral disc herniations, refer to protrusions of the cartilage of the intervertebral disc through the vertebral body endplate and into the adjacent vertebra. The protrusions may contact the marrow of the vertebra, leading to inflammation. Epidemiology Quies...

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 radiograph. Epidemiology occurs in ~5% (range 0.4-8%) o...

Rugger jersey spine (hyperparathyroidism)

Rugger jersey spine describes the prominent endplate densities at multiple contiguous vertebral levels to produce an alternating sclerotic-lucent-sclerotic appearance. This mimics the horizontal stripes of a rugby jersey. This term and pattern are distinctive for hyperparathyroidism 1. However ...

Pine cone bladder

A pine cone bladder or Christmas tree bladder is a cystographic appearance in which the bladder is elongated and pointed with a thickened, trabeculated wall. It is typically seen in severe neurogenic bladder with increased sphincter tone (detrusor sphincter dyssynergia) due to suprasacral lesion...

Persistent ossiculum terminale

The ossiculum terminale appears as a secondary ossification center of the dens between 3-6 years and normally fuses by 12 years. Failure of fusion results in a persistent ossiculum terminale (also called Bergmann's ossicle or ossiculum terminale of Bergmann) and is considered a normal anatomical...

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...

Neurogenic bladder

Neurogenic bladder is a term applied to a dysfunctional urinary bladder that results from any lack of coordination between the central nervous system and the somatic nervous system, 5 including injuries to the central or peripheral nerves that control and regulate urination. Injury to the brain,...

Myelitis

Myelitis is a collective term simply referring to any inflammation of the spinal cord. It is a form of myelopathy. The two major sub types include: leukomyelitis multiple sclerosis ADEM transverse myelitis ideopathic transverse myelitis secondary transverse myelitis: viral, neurosyphilis ...

Vertebral metastases

Vertebral metastases represent the secondary involvement of the vertebral spine by hematogenously-disseminated metastatic cells. They must be included in any differential diagnosis of a spinal bone lesion in a patient older than 40 years. This article will focus only on the metastasis involving...

Meninges

The meninges (singular: meninx) is a collective term for the three membranes that cover the brain and spinal cord and are covered in separate articles: cranial meninges spinal meninges History and etymology The word meninges arises from the Ancient Greek meninx meaning "membrane" 1.

Lumbar disc disease

Lumbar disc disease is a very common entity with a high asymptomatic prevalence. Intervertebral disc abnormalities are found in 25% of individuals below the age of 60, and over 50% in those over the age of 60. It is therefore not enough to demonstrate a disc lesion in someone with non-specific b...

Low endplate signal on T1

Several conditions may give vertebral endplate T1 low signal on MRI. They include: ankylosing spondylitis vertebral metastases disc infection haemodialysis

Limbus vertebra

A limbus vertebra is a well-corticated unfused secondary ossification center of the vertebral body, usually of its anterosuperior corner, that occurs secondary to herniation of the nucleus pulposus through the vertebral body endplate beneath the ring apophysis (see ossification of the vertebrae)...

Leptomeningeal metastases

Leptomeningeal metastases, also known as carcinomatous meningitis and meningeal carcinomatosis, refers to the spread of malignant cells through the CSF space. These cells can originate from primary CNS tumors (e.g. in the form of drop metastases), as well as from distant tumors that have metasta...

Jefferson fracture

Jefferson fracture is the eponymous name given to a burst fracture of the atlas. It was originally described as a four-part fracture with double fractures through the anterior and posterior arches, but three-part and two-part fractures have also been described. Epidemiology Associations 50% a...

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...

Insufficiency fracture

Insufficiency fractures are a type of stress fracture, which are the result of normal stresses on abnormal bone. Looser zones are also a type of insufficiency fracture. They should not be confused with fatigue fractures which are due to abnormal stresses on normal bone, or with pathological frac...

Hyperparathyroidism

Hyperparathyroidism is the effect of excess parathyroid hormone in the body. It can be primary, secondary, or tertiary. There are many characteristic imaging features, predominantly involving the skeletal system. It accounts for the 'H' in the popular mnemonic for lucent bone lesions FEGNOMASHI...

Hydromyelia

In hydromyelia, there is dilatation of the central canal of the spinal cord. The dilatation is lined by the normal ependymal lining of the central canal. The term can refer to dilatation of the persistent central canal of the spinal cord which communicates with the fourth ventricle (cavity wall...

Hangman fracture

Hangman fracture, also known as traumatic spondylolisthesis of the axis, is a fracture which involves the pars interarticularis of C2 on both sides, and is a result of hyperextension and distraction. Epidemiology These injuries account for 4-7% of all cervical spine fractures and up to 22% of ...

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...

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 ...

Extension teardrop fracture

Extension teardrop 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. Extension ...

Epidural lipomatosis

Epidural lipomatosis refers to an excessive accumulation of fat within the spinal epidural space resulting in compression of the thecal sac. In severe cases, compression may be symptomatic. The lumbar region is most frequently affected. Epidemiology The demographics of affected individuals ref...

Neuromyelitis optica spectrum disorder

Neuromyelitis optica (NMO) and neuromyelitis optica spectrum disorder (NMOSD) are closely related severe demyelinating diseases caused by an autoantibody to the aquaporin-4 water channel. The classic presentation of NMO is with the triad of optic neuritis, longitudinally extensive myelitis, and ...

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...

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 secondary to enthesitis 1. It is possible for the radiodense line to extend into the sacrum 2...

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...

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. Epidemiology The prevalence of CMT in one Norwegian study was 82.3 cases per 100,000 people 4. Clini...

Cervical canal stenosis

Cervical canal stenosis is a general term that refers to the abnormal narrowing of the cervical spinal canal that compromises the nerve root and/or spinal cord resulting in radiculopathy and/or compressive myelopathy. The most common cause of cervical spinal canal stenosis is age-related degener...

Cervical spine fractures

Cervical spine fractures can occur secondary to exaggerated flexion or extension, or because of direct trauma or axial loading. Epidemiology Males are affected more commonly than females with a median age of injury of 56 years. Falls, motor vehicle collisions, pedestrian accidents, cycling and...

Calcium pyrophosphate dihydrate deposition disease

Calcium pyrophosphate dihydrate deposition (CPPD) disease, also known as pyrophosphate arthropathy or pseudogout, is defined by the co-occurrence of arthritis with evidence of CPPD deposition within the articular cartilage. Terminology The terminology regarding CPPD disease has been confusing...

Bamboo spine (ankylosing spondylitis)

Bamboo spine is a pathognomonic radiographic feature seen in ankylosing spondylitis that occurs as a result of vertebral body fusion by marginal syndesmophytes. It is often accompanied by fusion of the posterior vertebral elements as well. A bamboo spine typically involves the thoracolumbar and...

Baastrup disease

Baastrup disease/syndrome (also referred to as kissing spines) is a cause of low back pain characterized by interspinous bursitis and other degenerative changes of the bones and soft tissues where adjacent spinous processes in the lumbar spine rub against each other. Epidemiology It tends to b...

Atlanto-axial subluxation

Atlanto-axial subluxation is a disorder of C1-C2 causing impairment in rotation of the neck. The anterior facet of C1 is fixed on the facet of C2. It may be associated with dislocation of the lateral mass of C1 on C2. Epidemiology Atlanto-axial subluxations are often associated with high energ...

Arachnoid cyst

Arachnoid cysts are relatively common benign and asymptomatic lesions occurring in association with the central nervous system, both within the intracranial compartment (most common) as well as within the spinal canal. They are usually located within the subarachnoid space and contain CSF. On ...

Ankylosing spondylitis

Ankylosing spondylitis (less commonly known as Bechterew disease or Marie Strümpell disease) is a seronegative spondyloarthropathy, which results in fusion (ankylosis) of the spine and sacroiliac (SI) joints, although involvement is also seen in large and small joints. Epidemiology Traditional...

Achondroplasia

Achondroplasia is a congenital genetic disorder resulting in rhizomelic dwarfism and is the most common skeletal dysplasia. It has numerous distinctive radiographic features. Epidemiology It occurs due to sporadic mutations in the majority of cases but can be inherited as an autosomal dominan...

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