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.
More than 200 results
Article
Gluteus maximus muscle
The gluteus maximus (plural: glutei maximi) is the largest muscle in the gluteal region and overlies most of the other gluteal muscles.
Summary
origin
gluteal surface of the ilium behind the posterior gluteal line
the lumbar fascia
lateral mass of sacrum
sacrotuberous ligament
insertion: ...
Article
Total knee arthroplasty
Total knee arthroplasty (TKA), total knee replacement (TKR), or tricompartmental knee replacement is an orthopedic procedure whereby the three articular surfaces of the knee (femoral, tibial, and patellar) are replaced by prosthetic components.
TKA is the most common joint arthroplasty performe...
Article
Marginal cord insertion
Marginal cord insertion, also known as a 'battledore insertion', is a type of abnormal cord insertion.
Terminology
Insertion of the umbilical cord within <2 cm from the placental margin is described as marginal cord insertion (usually defined as <2 cm 5, although some references define it as <...
Article
Pyramidal lobe of thyroid
The pyramidal lobe of the thyroid, also known as Lalouette pyramid 5, is a normal anatomic variant representing a superior projection of thyroid parenchyma arising from the thyroid isthmus.
Epidemiology
A pyramidal lobe is present in ~20 (range 10-30%) of the population ref and is commonly se...
Article
Polycystic ovarian syndrome
Polycystic ovarian syndrome (PCOS), also known as hyperandrogenic anovulation, is a chronic anovulation syndrome associated with androgen excess.
Terminology
"Hyperandrogenic anovulation" has been proposed as a more accurate and potentially less confusing term, as the ovarian feature is of mu...
Article
Metatarsal
The metatarsals consist of five long bones in the foot. They are numbered from 1st to 5th from the medial side of the foot to lateral. They are analogous to the metacarpals of the hand.
Gross anatomy
The metatarsal bones run from the tarsus, forming the tarsometatarsal joints, to the base of p...
Article
Hip-knee-ankle angle
The hip-knee-ankle angle (HKA) measures the angulation between the mechanical axes of the femur and tibia 1. The HKA is useful in quantifying the degree of valgus or varus alignment in the knee. It is also used in assessing post-operative knee alignment after total knee replacement 1.
Measureme...
Article
Cervical spine (flexion and extension views)
The cervical spine flexion and extension views demonstrate the seven vertebrae of the cervical spine when the patient is in a lateral position.
Indications
These views are specialized projections often requested to assess for spinal stability.
Note, such functional views should not be perform...
Article
Ascending colon
The ascending colon is the second part of the large bowel.
Gross anatomy
The ascending colon is the continuation of the cecum superior to the ileocecal valve. It is 15 cm in length and is secondarily retroperitoneal, although it has its own mesentery in approximately 25% of patients 1,2.
The ...
Article
Ankle series
The ankle series is comprised of an anteroposterior (AP), mortise and lateral radiograph. The series is often used in emergency departments to evaluate the distal tibia, distal fibula, and the talus; forming the ankle joint.
See approach to an ankle series.
Terminology
Mortise and mortice are...
Article
Metopic suture
The metopic suture (also known as the frontal, interfrontal, or median frontal suture) is a vertical fibrous joint that divides the two halves of the frontal bone and is present in a newborn.
Persistent metopic sutures can be misdiagnosed as vertical skull fractures, therefore it is important t...
Article
Usual interstitial pneumonia
Usual interstitial pneumonia (UIP) is not a disease, it is a histopathologic and radiologic pattern of interstitial lung disease. This can be caused by idiopathic pulmonary fibrosis, fibrotic hypersensitivity pneumonitis or non-specific interstitial pneumonia. The diagnosis is typically decided ...
Article
Peyronie disease
Peyronie disease is the most common cause of painful penile induration. Fibrous tissue plaques form within the penile tunica albuginea, causing painful deformity and shortening of the penis. Though clinical diagnosis is usually accurate, the role of imaging is to evaluate extension of plaques, w...
Article
Medulloblastoma, WNT-activated
Medulloblastoma, WNT-activated is the least common type of medulloblastoma and has by far the best prognosis, with the vast majority achieving cure with appropriate therapy. They are usually seen in children and, to a lesser degree, adults. They typically arise from the region surrounding the fo...
Article
Medulloblastoma
Medulloblastomas are the most common malignant brain tumors of childhood, most often presenting as midline masses in the roof of the 4th ventricle (at the superior medullary velum) with associated mass-effect and hydrocephalus. Treatment typically consists of surgical resection, radiation therap...
Article
Rapidly destructive osteoarthritis of the hip
Rapidly destructive osteoarthritis of the hip, also known as rapidly progressive osteoarthritis of the hip, is a rare chondrolysis of unknown etiology which can progress to complete destruction of the femoral head. It is a diagnosis of exclusion.
Epidemiology
It is most common in 60-70 year ol...
Article
Charcot joint causes (mnemonic)
The causes of a Charcot joint can be remembered, using a mnemonic - with a little poetic license - as they (all) start with the letter S.
Mnemonic
s: sugar (diabetes)
s: syphilis
s: steroid use
s: syringomyelia
s: spinal cord injury
s: spina bifida
s: scleroderma
s: scaly disease (lepro...
Article
Diabetes mellitus
Diabetes mellitus (DM), often referred to simply as diabetes, is a group of metabolic conditions characterized by hyperglycemia.
These conditions should not be confused with diabetes insipidus which is clinically distinct and not related to hyperglycemia.
Terminology
If a patient with diabet...
Article
Charcot joint
Charcot joint, also known as a neuropathic joint or Charcot (neuro/osteo)arthropathy, refers to a progressive degenerative/destructive joint disorder in patients with abnormal pain sensation and proprioception.
Epidemiology
In modern Western societies by far the most common cause of Charcot jo...
Article
Nasogastric tube positioning
Assessment of nasogastric (NG) tube positioning is a key competency of all doctors as unidentified malpositioning may have dire consequences, including death.
Radiographic features
Plain radiograph
A correctly placed nasogastric tube should 10:
descend in the midline, following the path of ...