Articles
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16,928 results
Article
Trapezium
The trapezium (also known as the greater multangular) is one of the eight carpal bones of the hand. It is the most lateral (radial) bone of the distal row, located between the scaphoid and the first metacarpal bone. It articulates with the scaphoid proximally, the trapezoid medially, and the thu...
Article
Erosive osteoarthritis
Erosive (inflammatory) osteoarthritis is a form of hand osteoarthritis (OA) where, as the name implies, there is an additional erosive/inflammatory component.
Epidemiology
There is marked female predilection (F:M ~12:1), typically presenting in the postmenopausal patient.
Clinical presentatio...
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Breast imaging-reporting and data system (BI-RADS) assessment category 5
BI-RADS 5 lesions under the BI-RADS (breast imaging reporting and data system) refer to breast lesions that are highly suspicious for malignancy, requiring appropriate action to be taken (i.e. biopsy and management as appropriate). BI-RADS 5 lesions have the characteristic morphology of breast c...
Article
Bullet-shaped vertebra
Bullet-shaped vertebra, also known as ovoid vertebra, refers to the anterior beaking of the vertebral body.
It is seen in the following conditions:
mucopolysaccharidosis
Hurler disease usually with inferior beaking
Morquio disease often with central beaking
achondroplasia
congenital hypoth...
Article
Central nervous system germinoma
Intracranial germinomas, also known as dysgerminomas or extra-gonadal seminomas, are a type of germ cell tumor and are predominantly seen in pediatric populations. They tend to occur in the midline, either at the pineal region (majority) or along the floor of the third ventricle/suprasellar regi...
Article
Hurler syndrome
Hurler syndrome is one of the mucopolysaccharidoses (MPS type I).
Epidemiology
The estimated incidence is ~1:100,000.
Clinical presentation
It manifests in the first years of life with intellectual disability, corneal clouding, deafness, and cardiac disease. Death usually occurs within the f...
Article
Mucopolysaccharidoses
Mucopolysaccharidoses (MPS) constitute a group of hereditary disorders, one of a number of lysosomal storage disorders, having in common an excessive accumulation of mucopolysaccharides secondary to deficiencies in specific enzymes (lysosomal hydrolases) responsible for degradation of mucopolysa...
Article
Tuberculous spondylitis
Tuberculous spondylitis, also known as Pott disease, refers to vertebral body osteomyelitis and intervertebral discitis from tuberculosis (TB). The spine is the most frequent location of musculoskeletal tuberculosis, and commonly related symptoms are back pain and lower limb weakness/paraplegia....
Article
Chronic osteomyelitis
Chronic osteomyelitis is a form of osteomyelitis that is defined as a progressive inflammatory process resulting in bone destruction and sequestrum formation. Bacteria and fungi can cause it, and it may present as recurrent or intermittent disease.
Terminology
Chronic osteomyelitis is where sy...
Article
Spinal meningeal cyst
Spinal meningeal cysts are diverticula of the arachnoid or dura mater or of the nerve root sheath. They are uncommon, usually asymptomatic and typically found incidentally on MRI.
Clinical presentation
They cysts are usually asymptomatic, but if they are large, they may cause mass effect and ...
Article
Spinal arachnoid cyst
Spinal arachnoid cysts are relatively uncommon and may be either intradural (type III meningeal cyst) or extradural (type IA meningeal cyst).
This article specifically focuses on spinal arachnoid cysts. For a general discussion of arachnoid cysts, refer to the main article: arachnoid cyst.
Epi...
Article
Invasive breast carcinoma of no special type
Invasive breast carcinoma of no special type, previously known as invasive ductal carcinoma, not otherwise specified, is the most common type of breast cancer (70-80%) 5. It is an infiltrating and malignant proliferation of neoplastic cells in the breast tissues.
Terminology
The 4th edition (2...
Article
Inflammatory carcinoma of the breast
Inflammatory carcinoma of the breast, also referred to as inflammatory breast cancer, is a relatively uncommon but aggressive form of invasive breast carcinoma with a characteristic clinical presentation and unique radiographic appearances.
Epidemiology
Inflammatory carcinomas account for 1...
Article
Mastitis
Mastitis (rare plural: mastitides) refers to inflammation of the breast parenchyma, of which there are a number of subtypes:
acute mastitis
puerperal mastitis usually occurs from infection with Staphylococcus spp. during lactation
non-puerperal mastitis: not related to lactation and usually o...
Article
Trough line sign
The trough line sign is a sign of posterior shoulder dislocation on AP shoulder radiograph.
Pathology
In a posterior dislocation, the anterior aspect of the humeral head becomes impacted against the posterior glenoid rim. With sufficient force, this causes a compression fracture on the anteri...
Article
Patellotrochlear index
Patellotrochlear index (PTI) is one of the methods to determine patellar height.
Measurement
The patellotrochlear index is measured on a sagittal MR image with the maximal patellar cartilage thickness and the maximal craniocaudal diameter of the patella.
Two measurements are made:
A: the le...
Article
Gadolinium contrast agents
Gadolinium-based contrast media (GBCM), gadolinium-based contrast agents (GBCAs), or simply gadolinium contrast agents, are molecular complexes containing the rare earth metal gadolinium, chelated to a carrier ligand. They are a type of paramagnetic contrast agent, which are the primary class of...
Article
Unicompartmental knee arthroplasty
Unicompartmental knee arthroplasties (UKA) or replacements (UKR) are orthopedic procedures where either the medial or lateral articular surfaces of the knee are replaced by prostheses 1. This differs from patellofemoral arthroplasties, which replace the patellar and trochlear groove articular su...
Article
Colorectal cancer
Colorectal cancer (CRC) is the most common cancer of the gastrointestinal tract and is one of the most frequently diagnosed malignancies in adults. CT is the mainstay for colon cancer locoregional staging and MRI is the mainstay for rectal cancer locoregional staging.
This article focuses on co...
Article
Subsidence
In a medical sense, subsidence refers to the collapse or settling of bone located immediately next to an implantable device in direction of the loading force. It can lead to a loss of the desired postoperative result and to further complications 1.
Epidemiology
Associations
Subsidence can be ...