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.
3,660 results found
Article
Blade plate
Blade plates, also known as angled blade plates, are a type of orthopedic hardware used for reconstructing subtrochanteric femoral fractures, including therapeutic fractures during derotational osteotomies.
Blade plates were an advance on earlier fixation nails such as the Y nail or the Zicker ...
Article
Block vertebra
Block vertebra is a type of vertebral anomaly where there is a failure of separation of two or more adjacent vertebral bodies. It is an anatomic variant.
Pathology
In a block vertebra, there is partial or complete fusion of adjacent vertebral bodies.
Associations
hemivertebrae/absent vertebr...
Article
Bloom syndrome
Bloom syndrome is a rare autosomal recessive disorder characterized by short stature, brachydactyly, malar hypoplasia and facial telangiectasia, erythema and cafe au lait spots. Affected individuals have an increased risk of developing malignancies.
Pathology
There is extreme chromosomal fragi...
Article
Blount disease
Blount disease refers to a local disturbance of growth of the medial aspect of the proximal tibial metaphysis and/or epiphysis that results in tibia vara. The condition is commonly bilateral.
Epidemiology
There is no recognized inheritance pattern.
Clinical presentation
Clinically, the chi...
Article
Blow out bone metastases
Blow out bone metastases or expansile bone metastases are typically only encountered in a relatively small number of primary malignancies, including 1:
renal cell carcinoma
thyroid cancer
hepatocellular carcinoma
pheochromocytoma
melanoma
gastric carcinoma
Occasionally the sclerotic metas...
Article
Blumensaat line
Blumensaat line, also known as the intercondylar line, is the line drawn along the roof of the intercondylar notch of the femur on a sagittal view of the knee.
It can be used for:
indicating the relative position of the patella - normally intersects the lower pole of the patella
evaluating fo...
Article
Bochdalek hernia
Bochdalek hernias , also known as pleuroperitoneal hernias, (alternative plural: herniae) are the commonest type of congenital diaphragmatic hernia. They occur posteriorly and are due to a defect in the posterior attachment of the diaphragm when there is a failure of pleuroperitoneal membrane cl...
Article
Body imaging
Body imaging is the term assigned to cross-sectional imaging of the body, which radiologically refers to the chest, abdomen and pelvis. It is often used by radiologists who report this region (sometimes known as body imagers/radiologists) to differentiate their primary area of interest from othe...
Article
Body of sphenoid
The body of the sphenoid bone is the midline cubical portion of the sphenoid bone, hollowed by the sphenoid air sinuses.
Gross anatomy
The body has superior, inferior, anterior, posterior, and lateral surfaces.
The superior surface features:
ethmoidal spine: prominent spine that articulates...
Article
Böhler angle
Böhler angle, also written as Bohler angle or Boehler angle, is also called the calcaneal angle or tuber joint angle 1, and is the angle between two lines tangent to the calcaneus on the lateral radiograph. These lines are drawn tangent to the anterior and posterior aspects of the superior calca...
Article
Bone age assessment
Bone age assessment is used to radiologically assess the biological and structural maturity of immature patients from their hand and wrist x-ray appearances. It forms an important part of the diagnostic and management pathway in children with growth and endocrine disorders. It is helpful in the ...
Article
Bone age (radiograph)
The bone age radiograph of the hand and wrist is a commonly performed examination to determine the radiographic age of the patient via the assessment of growth centers.
Indications
Bone age radiographs may be indicated for both clinical and non-clinical purposes 6,7:
for the investigation of
...
Article
Bone bruise
Bone bruises (also known as bone contusion, trabecular microfracture) are an osseous injury that results from compression of bone structures.
Pathology
Bone bruises represent trabecular microfractures with hemorrhage and without a discrete fracture line or contour abnormality 4. They typically...
Article
Bone cortical lesions (mnemonic)
A mnemonic for bony cortical lesions is:
Fear Of Missing Out S
Mnemonic
F: fibrosarcoma
O: osteoid osteoma
M: metastasis
O: osteomyelitis
S: stress fracture
Article
Bone deformity from softening
Conditions associated with bone deformity from softening includes:
hourglass thorax
bowing of long bones
acetabular protrusion
buckled/compressed pelvis
biconcave vertebral bodies / codfish vertebra
Article
Bone-forming tumors
Bone-forming tumors are a subset of bone tumors that are characterized by their propensity to form excess osteoid. They can be further subdivided into benign and malignant tumors.
Benign tumors
osteoid osteoma
osteoblastoma
bone island (enostosis)
osteopoikilosis
osteoma
ossifying fibroma...
Article
Bone infarction
Bone infarction is a term used to refer to osteonecrosis within the metaphysis or diaphysis of a bone. Necrosis is a type of cell death due to irreversible cell injury, which can be recognized microscopically by alterations in the cytoplasm (becomes eosinophilic) and in the nucleus (swelling, py...
Article
Bone lesion description (mnemonic)
A mnemonic for describing bone lesions (of any type) in a logical order:
All Sensible People Must Make Clear/Proper Sense
CAMPS
Mnemonic
A: age (maturity of skeleton)
S: site (bone name and location within bone) and size
P: pattern of destruction (lytic lesions)
M: margins (transition zon...
Article
Bone lesions with sequestrum
There are several bony lesions that can involve or produce a sequestrum.
They include:
Common
Brodie abscess: osteomyelitis
Less common
eosinophilic granuloma
certain soft tissue tumors (with bony extension)
malignant fibrous histiocytoma
lymphoma
metastasis (especially from breast ca...
Article
Bone macroscopic structure
Bone macroscopic structure allows a bone to be divided into regions based on position or morphology. This is important for a number of reasons including how growth may be affected by injury.
Bones can be separated into:
diaphysis
metaphysis
metaepiphysis
metadiaphysis
epiphysis
physis
ap...
Article
Bone marrow
Normal bone marrow is divided into red and yellow marrow, a distinction made on the grounds of how much fat it contains.
Gross anatomy
Red marrow is composed of:
hematopoietic cells
supporting stroma
reticulum (phagocytes and undifferentiated progenitor cells)
scattered fat cells
a rich v...
Article
Bone marrow edema
Bone marrow edema is the term given to abnormal fluid signal seen within the bone marrow on MRI. It is a non-specific, yet important finding usually indicating the presence of underlying pathology.
Pathology
Etiology
There is a long (long) list of possible causes of this finding:
primary: bo...
Article
Bone marrow edema syndrome
Bone marrow edema syndrome refers to a group of transient, self-limiting clinical entities of unknown cause, which are associated with the presence of bone marrow edema pattern.
These conditions include:
transient osteoporosis of the hip
bone marrow edema syndrome of the foot and ankle
regio...
Article
Bone marrow edema syndrome of the foot and ankle
Bone marrow edema syndrome of the foot and ankle, also known as transient bone marrow edema syndrome of the foot and ankle, refers to the presence of self-limited, patchy bone marrow T2 hyperintensities in the bones of the ankle and/or foot of unknown etiology. It is related to transient osteopo...
Article
Bone mineral density
Bone mineral density (BMD) is defined as the amount of mineral (calcium hydroxyapatite) per unit of bone and can be used as an indirect indicator of bone strength. The bone mineral density is used to determine if osteopenia or osteoporosis are present.
Radiographic features
Bone mineral densit...
Article
Bone scintigraphy
Bone scintigraphy (a.k.a. bone scans) are a nuclear medicine (scintigraphic) study that makes use of technetium-99m (commonly Tc-99m-methylene diphosphonate (MDP)) as the active agent.
The study has three phases which follow intravenous injection of the tracer. Sometimes a fourth (delayed/delay...
Article
Bones of the lower limb
The bones in the lower limb can be divided into those within the thigh and leg (4) and those within the foot (26).
Bones of the thigh and leg
femur
patella
tibia
fibula
Bones of the foot
calcaneus
talus
navicular
medial cuneiform
intermediate cuneiform
lateral cuneiform
cuboid
meta...
Article
Bones of the upper limb
The bones in the upper limb are those that can be found within the pectoral girdle (3), arm (1) forearm (2), and hand (27). There are also a number of accessory ossicles, predominantly occurring at the wrist. Bones provide sites of attachment for skeletal muscles as well as a framework to neurov...
Article
Bones types
There are many types of bone within the body:
long bones (longer than they are wide)
short bones (not long bones)
flat bones
sesamoid bones (for within a tendon)
irregular bones (don't fit into a category)
The majority of the bones of the appendicular skeleton are long bones. However, the ...
Article
Bone tumors
There are a bewildering number of bone tumors with a wide variety of radiological appearances:
bone-forming tumors
osteoid osteoma
osteoblastoma
osteoma
osteosarcoma
cartilage-forming tumors
enchondroma
enchondromatosis-Ollier disease
Maffucci syndrome
osteochondroma:
hereditary multi...
Article
Bone within a bone appearance
Bone within a bone is a descriptive term applied to bones that appear to have another bone within them. There are numerous causes including:
normal
thoracic and lumbar vertebrae (neonates and infants)
growth recovery lines (after infancy)
cortical splitting and new periostitis
sickle cell d...
Article
Bone within a bone appearance (mnemonic)
A useful mnemonic to remember the possible etiologies of a bone within a bone appearance is:
GHOST DRAGON
Mnemonic
G: growth arrest lines
H: heavy metals, hypoparathyroidism, hypothyroidism
O: osteopetrosis
S: sickle cell anemia, scurvy, syphilis
T: thalassemia, tuberculosis
D: disease o...
Article
Bony humeral avulsion of the glenohumeral ligament lesion
Bony humeral avulsion of the glenohumeral ligament (BHAGL) lesion is just like its slightly shorter relative HAGL lesion, except as the name suggests a bony avulsion fracture is seen at humeral insertion of the inferior glenohumeral ligament.
It is often associated with a subscapularis tear, an...
Article
Bony lesions without periostitis or pain (mnemonic)
A mnemonic to help remember bony lesions that have no pain or periostitis is:
E FUN
Mnemonic
E: enchondroma
F: fibrous dysplasia
U: unicameral bone cyst
N: non-ossifying fibroma
If periostitis or pain is present (assuming no trauma, which can be a foolhardy assumption), you can exclude E ...
Article
Bony pelvis
The bony pelvis is formed by the sacrum and coccyx and a pair of hip bones (os coxae or innominate bones), comprising the ischium, pubis and ilium and are part of the appendicular skeleton.
Its primary function is the transmission of forces from the axial skeleton to the lower limbs as well as...
Article
Bony sequestrum
The radiological definition of a bony sequestrum refers to an image of calcification within a lucent lesion, completely separated from the surrounding bone and without referring to the histological nature and vascular status of the calcified tissue 1.
The pathological definition of a sequestru...
Article
Bony sequestrum (mnemonic)
Mnemonics to help remember common causes of bony sequestrum include:
E-FILM
LIFE
FILE
Mnemonics
E-FILM
E: eosinophilic granuloma
F: fibrosarcoma
I: infection (Brodie abscess)
L: lymphoma (skeletal)
M: malignant fibrous histiocytoma or metastasis (especially from breast carcinoma)
LI...
Article
Bony skeleton
The skeleton is the complete set of bones that make up a human. There are 206 bones in total which can be divided into:
axial skeleton
appendicular skeleton
Article
Bony trabeculae of proximal femur
The proximal femur has four major groups of trabeculae, distributing the compressive and tensile forces from the femoral head into the femoral diaphysis through the femoral neck. Together these trabeculae create the Ward triangle. The individual trabecular groups include:
principal compressive ...
Article
Boogard's angle
Boogard's angle is measured by drawing a line from basion to opisthion and another line along the plane of the clivus to the basion intersecting the first line - the angle between these two lines is measured.
The normal angle is 126° +/- 6°. If the angle measures more than 136° it is indicative...
Article
Boomerang sign (disambiguation)
Boomerang sign may refer to:
boomerang sign (peroneus brevis tear)
boomerang sign (medial meniscal tear)
boomerang sign (splenium)
History and etymology
Boomerang is of course a curved projectile used originally by the Australian Aborigines, one of its various uses was as a hunting weapon 1.
Article
Boomerang sign (knee)
The boomerang sign is defined as a small displaced flap from a longitudinal horizontal type medial meniscal tear which is displaced inferiorly into the medial meniscotibial recess. The imaging diagnosis of this type of tear is crucial because it is normally hidden from the surgeon during routine...
Article
Bornholm disease
Bornholm disease, also known as epidemic pleurodynia, is a virally-mediated myositis presenting as recurrent episodes of acute severe pleuritic pain. It is usually self-limiting, and serious morbidity is rare.
Epidemiology
Its true incidence is unknown and it is thought that it is underdiagnos...
Article
Bosworth fracture
The term Bosworth fracture is no longer used. However, it was classically used to refer to a fracture-dislocation of the ankle in which there was fracture of the fibula and posterior dislocation of the talus.
History and etymology
Named after David M Bosworth (1897-1979), orthopedic surgeon fr...
Article
Both hands series (summary)
This is a basic article for medical students and other non-radiologists
Both hands series (or both hands x-ray) is an investigation almost exclusively performed in the rheumatology service to assess patients with arthritis. It is not used in trauma.
Reference article
This is a summary article...
Article
Botryoid rhabdomyosarcoma
Botryoid rhabdomyosarcoma, also known as sarcoma botryoides, is a type of embryonal rhabdomyosarcoma and accounts for 5-10% of all rhabdomyosarcomas 6.
Epidemiology
It tends to occur in pediatric population, often between birth and 15 years of age 7.
Pathology
Rhabdomyosarcomas generally ha...
Article
Bouchard node
Bouchard nodes are a clinical sign relating to bony nodules of the proximal interphalangeal joints and are much less common than Heberden nodes. They generally (but not always) correspond to palpable osteophytes.
Clinical presentation
They are sometimes painful, and are typically associated wi...
Article
Boutonnière deformity
Boutonnière deformity is the eponymous name of a musculoskeletal manifestation of rheumatoid arthritis presenting in a digit, with the combination of:
flexion contracture of a proximal interphalangeal (PIP) joint
extension of a distal interphalangeal (DIP) joint
Pathology
Boutonnière deformi...
Article
Bowdler spurs
Bowdler spurs refer to transverse long bone midshaft spurs or osteochondral projections associated with hypophosphatasia. They typically occur in the fibulae and less commonly in the forearms.
Article
Bowing fracture
Bowing fractures are incomplete fractures of tubular long bones in pediatric patients (especially the radius and ulna) that often require no intervention and heal with remodeling.
Epidemiology
Bowing fractures are almost exclusively found in children. However, there have been several case repo...
Article
Bowl of grapes sign
The bowl of grapes sign has been described in synovial sarcoma. It refers to the characteristic multilobulated lesion subdivided by multiple septa, forming large cystic foci with regions of hemorrhage.
Article
Boxer fracture
Boxer fractures are minimally comminuted, transverse fractures of the 5th metacarpal neck, and are the most common type of metacarpal fracture.
A boxer's knuckle is a separate entity, which is a tear of the metacarpophalangeal joint sagittal band that causes subluxation of the associated exten...
Article
Boxer knuckle
Boxer knuckle (not to be confused with a Boxer fracture) refers to an appearance when there is a disruption to the sagittal bands of the extensor hood, particularly over the metacarpophalangeal (MCP) joint.
Pathology
It often tends to result when a clench fisted hand strikes an object in a tra...
Article
Boyd amputation
Boyd amputation refers to amputation at the level of the ankle with preservation of the calcaneus and heel pad and consequent fixation of the calcaneus to the tibia. It allows for complete weight bearing and provides both stabilization of the heel pad and suspension for a prosthesis.
Article
Brachialis muscle
The brachialis muscle (brachialis) is one of the three muscles of the anterior compartment of the arm. It is only involved in flexion at the elbow and therefore the strongest flexor at the elbow, compared with the biceps brachii which is also involved in supination because of its insertion on th...
Article
Brachial plexitis
Brachial plexitis refers to inflammatory change involving the brachial plexus. This is in contrast to a brachial plexopathy meaning any form of pathology involving the brachial plexus.
Epidemiology
Brachial plexitis is more commonly seen in men between 30 and 70 years of age and is bilateral i...
Article
Brachial plexus
The brachial plexus is a complex neural network formed by lower cervical and upper thoracic ventral nerve roots which supplies motor and sensory innervation to the upper limb and pectoral girdle. It is located in the neck extending into the axilla posterior to the clavicle.
Summary
origin: ven...
Article
Brachial plexus injuries
Brachial plexus injuries are a spectrum of upper limb neurological deficits secondary to partial or complete injury to the brachial plexus, which provides the nerve supply of upper limb muscles.
Clinical presentation
Trauma, usually by motor vehicle accidents, involves severe traction on the ...
Article
Brachial plexus terminal branches (mnemonic)
A useful mnemonic for brachial plexus terminal branches includes:
Most Alcoholics Must Really Urinate
Mnemonic
Where the first letter of each word represents the terminal branches of the brachial plexus:
M: musculocutaneous nerve
A: axillary nerve
M: median nerve
R: radial nerve
U: ulnar...
Article
Brachioradialis muscle
Brachioradialis muscle is a flexor at the elbow and works with biceps brachii and brachialis muscles. It is located in the superficial layer of the posterior compartment of the forearm and is particularly useful in elbow stabilization.
Despite the bulk of the muscle being visible from the anter...
Article
Brachycephaly
Brachycephaly refers to a calvarial shape where the bi-parietal diameter to fronto-occipital diameter approaches the 95th percentile. It can result from a craniosynostosis involving the coronal and lambdoid sutures.
Pathology
Associations
Brachycephaly can be associated with numerous syndrome...
Article
Brachydactyly
Brachydactyly (BD) essentially refers to short digits. It is often inherited as an autosomal dominant trait (all the types). The clinical spectrum can widely range from minor digital hypoplasia to complete aplasia. As a group, it most commonly involves the middle phalanx 2. Single or multiple bo...
Article
Brachydactyly type A1 (Farabee type)
Brachydactyly type A1, also known as Farabee type brachydactyly, is a subtype of brachydactyly.
Clinical presentation
The anomaly is characterized by hypoplasia or aplasia of middle phalanges of the second to fifth digits in hands and feet and proximal phalanges of the thumbs and great toes...
Article
Brachydactyly type A2 (Mohr-Wriedt type)
Brachydactyly type A2 or Mohr-Wriedt type is characterized by hypoplasia/aplasia of the second middle phalanx of the index finger, second toe and sometimes little finger. There is radial deviation of the index finger and tibial deviation of the second toe.
Pathology
Type A2 brachydactyly can b...
Article
Brachydactyly type A3
Brachydactyly type A3 is characterized by shortening of the middle phalanx of the little finger with radial deviation of distal phalanx. Slanting of the distal articular surface of the middle phalanx leads to radial deflection of the distal phalanx. However, it is not always associated with clin...
Article
Brachydactyly type A4 (Temtamy type)
Brachydactyly type A4 or Temtamy type is characterized by brachymesophalangy (absent or hypoplastic middle phalanx) of the second and fifth fingers. Other less common features include club foot, clinodactyly, ulnar deviation of the second finger.
Pathology
Like other brachydactyly, type A4 is ...
Article
Brachydactyly type A5
Brachydactyly type A5 is characterized by absence of the middle phalanges and nail dysplasia with duplicated terminal phalanx of the thumb with resultant bifid thumb. Inheritance is suggested as autosomal dominant.
Article
Brachymetatarsia
Brachymetatarsia (a.k.a. congenital short metatarsus) is a rare condition that develops from early closure of the growth plate.
Epidemiology
Females are almost exclusively affected 1.
Pathology
Location
It typically involves the fourth ray or, less frequently, more than one metatarsal bon...
Article
Brahma bull sign
The Brahma bull sign (or Brahman) describes the appearance of the femoral neck when an osteochondroma is present, as Brahma bulls have an odd, camel-like hump along the dorsum of their neck resembling a femoral neck osteochondroma. Osteochondromas of the femoral neck, particularly when sessile, ...
Article
Branchio-oculo-facial syndrome
Branchio-oculo-facial syndrome (BOFS) is a very rare autosomal dominant genetic disorder that is characterized clinically by abnormalities affecting the eyes, craniofacial structures, and branchial sinuses.
Epidemiology
More than 80 cases have been reported in the global literature since its f...
Article
Bridging of the pubic symphysis (differential)
Bridging (or fusion) of the pubic symphysis can be associated with various systemic and local causes, including 1-3:
ankylosing spondylitis
ochronosis
fluorosis
surgical fusion
post-traumatic
post-infectious
post-radiation therapy
osteoarthritis
rheumatoid arthritis
osteitis pubis
myo...
Article
Bright rim sign (anterior talofibular ligament injury)
The bright rim sign in anterior talofibular ligament injury refers to a sign seen on MRI. A cortical defect with a bright dot-like or curvilinear high-signal-intensity, usually at the fibular attachment site, is seen on MRI. It has been described as an indicator of ATFL injury 1.
See also
brig...
Article
British Athletics muscle injury classification
The British Athletics muscle injury classification (BAMIC/BAC) is a five-point MRI-based system that is based on extent and site. It has been primarily based on hamstring injuries but is used in other muscle injuries. The classification system has been shown to have moderate inter- and intra-rat...
Article
Brodie abscess
Brodie abscess is an intraosseous abscess related to a focus of subacute or chronic pyogenic osteomyelitis. Unfortunately, there is no reliable way to radiographically exclude a focus of osteomyelitis. It has a protean radiographic appearance and can occur at any location and in a patient of any...
Article
Brown adipose tissue
Brown adipose tissue (BAT) (also known as brown fat) is one of two types of adipose tissue (the other one being white fat) important for producing thermal energy (heat, non-shivering thermogenesis), especially in the newborn. It constitutes ~5% of body mass in the newborn and tends to reduce mar...
Article
Brown tumor
Brown tumor, also known as osteitis fibrosa cystica and rarely as osteoclastoma, is one of the manifestations of hyperparathyroidism. It represents a reparative cellular process, rather than a neoplastic process. Histologically brown tumors are identical to giant cell tumor (both are osteoclasto...
Article
Brucellosis
Brucellosis is a global zoonotic infection secondary to any of the four Brucella spp. that infect humans. It can be focal or systemic but has a particular affinity for the musculoskeletal system.
Epidemiology
Brucellosis occurs worldwide but is particularly prevalent in Mediterranean regions,...
Article
Brunelli procedure
Brunelli procedure is a surgical procedure aiming to reconstruct a torn scapholunate ligament by reconnecting the scaphoid and lunate using the flexor carpi radialis tendon 1. In the modified Brunelli technique the tendon is sutured upon itself, thereby preventing the crossing of the distal radi...
Article
Bucket handle fracture (disambiguation)
Bucket handle fracture may refer to:
bucket handle fracture - non-accidental injury
bucket handle fracture of the pelvis
Article
Bucket-handle meniscal tear
Bucket-handle meniscal tears are a type of displaced vertical meniscal tear where the inner part is displaced centrally. They more commonly occur in the medial meniscus and are often associated with anterior cruciate ligament (ACL) tears.
Radiographic features
MRI
Bucket-hand tears can manif...
Article
Buckle rib fracture
Buckle rib fractures are incomplete fractures involving only the inner cortex. They typically occur due to an anterior compressive force to the chest, most commonly external cardiac massage, but can be seen following any such traumatic injury.
Pathology
Buckle rib fractures occur in all ages, ...
Article
Buford complex
Buford complex is a congenital glenoid labrum variant where the anterosuperior labrum is absent in the 1-3 o'clock position and the middle glenohumeral ligament is thickened (cord-like). It originates directly from the superior labrum adjacent to the bicipital labral complex and inserts onto the...
Article
Bullet-shaped vertebra
Bullet-shaped or ovoid vertebra refers to the anterior beaking of the vertebral body.
It is seen in the following conditions:
mucopolysaccharidosis (Morquio disease, Hurler disease)
achondroplasia
congenital hypothyroidism
See also
weapons and munitions inspired signs
Article
Bunionette
A bunionette, also known as a tailor's bunion or metatarsus quintus varus, is a bony prominence at the lateral 5th metatarsal head. It is the lateral counterpart of the more common bunion of the first metatarsophalangeal joint, and when they occur together (often with spreading of the other meta...
Article
Bursa
Bursae are small fluid-filled sacs lined by a synovial membrane with an inner capillary layer of synovial fluid. It provides a cushion between bones and tendons and/or muscles around a joint. This helps to reduce friction between the bones and allows free movement. They may or may not communicat...
Article
Bursitis
Bursitis is inflammation of a bursa, a synovial membrane-lined space, present overlying a number of joints. The inflammation may be acute or chronic, in the later case calcification may be apparent on plain radiographs. MRI best illustrates the bursa and related pathology.
Specific pathological...
Article
Burst fracture
Burst fractures are a type of compression fracture related to high-energy axial loading spinal trauma that results in disruption of the posterior vertebral body cortex with retropulsion into the spinal canal.
Clinical presentation
They usually present as back pain and or lower limbs neurologi...
Article
Buschke-Ollendorff syndrome
Buschke-Ollendorff syndrome (BOS), also known as disseminated dermatofibrosis lenticularis 2, comprises of osteopoikilosis associated with disseminated connective tissue and cutaneous yellowish nevi, predominantly on the extremities and trunk 1. Recent genetic work has linked this syndrome to ...
Article
Busoga hernia
Busoga hernias, also known as Gill-Ogilvie hernias in Europe 1 (alternative plural: herniae), are a variant of the direct inguinal hernia involving the conjoint tendon.
Epidemiology
Busoga herniae have been noted to occur most commonly in young, athletic men with a well-developed abdominal mus...
Article
Butterfly fragment (fracture)
Butterfly fragments are large, triangular fracture fragments seen commonly in comminuted long bone fractures. The term is commonly used in orthopedic surgery, and results from two oblique fracture lines meeting to create a large triangular or wedge-shaped fragment located between the proximal an...
Article
Butterfly vertebra
Butterfly vertebra 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
Associations
anterior spina bifida +/- anterior meningocele
can be part of the Alagille syndr...
Article
Button sequestrum
A button sequestrum is a small sequestrum of devascularised bone surrounded by lucency. Although classically described in osteomyelitis and eosinophilic granuloma it is also occasionally seen in fibrosarcoma and lymphoma.
Differential diagnoses
osteoid osteoma
tuberculous osteomyelitis
radi...
Article
Buttress plate
Buttress plates are osteosynthetic implants commonly used in the metaphyseal area for internal fixation of articular fractures to support intraarticular fragments.
Usage
They are used to counteract vertical shear forces during axial loading in the metaphyseal area and to prevent sliding/shorte...