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.

2,639 results found
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Deep inguinal lymph nodes

The deep inguinal nodes lie medially to the femoral vein. There are around three in number and receive lymphatic channels that run with the deep femoral vessels and from the glans penis / clitoris from the perineum. There are common channels with the superficial inguinal nodes, and they drain in...
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Deep peroneal nerve

The deep peroneal (fibular) nerve is one of two terminal branches of the common peroneal nerve. Summary origin: the terminal branch of common peroneal nerve in the lateral compartment of the leg course: passes into the anterior compartment of the leg, where it courses inferiorly into the dors...
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Deep posterior compartment of the leg

The deep posterior compartment of the leg is one of the four compartments in the leg between the knee and foot. Muscles within this compartment primarily produce ankle plantarflexion and toe flexion, with exception of the popliteus which acts on the knee. Of the two posterior compartments, the d...
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Deep vein thrombosis

The term deep vein thrombosis (DVT) is practically a synonym for those that occur in the lower limbs. However, it can also be used for those that occur in the upper limbs and neck veins. Other types of venous thrombosis, such as intra-abdominal and intracranial, are discussed in specific section...
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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...
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Degloving injury

Degloving injuries can refer to a number of conditions: degloving soft tissue injury Morel-Lavallee lesion (closed degloving soft tissue injury) intramuscular degloving injury degloving bowel injury
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Degloving soft tissue injury

Degloving soft tissue injuries can be extensive and quite severe conditions. These may be open or, less commonly, closed injuries, which are known as Morel-Lavallee lesions. This article focuses on open injuries with closed injuries discussed in the Morel-Lavallee lesion article.  Terminology ...
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Dehiscence

Dehiscence is a general term referring to 'splitting open' and is used in a variety of contexts in medicine generally and radiology more specifically.  The two most common usages are: splitting open of a wound (e.g. sternal dehiscence) loss of bone separating one structure from another (e.g. ...
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Delayed bone age

A generalised retardation in skeletal maturation has different causative or aetiological factors, these can be classified as follows: chronic ill health congenital heart disease (especially cyanotic) chronic renal disease inflammatory bowel disease malnutrition: failure to thrive (FTT) ric...
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Delayed onset muscle soreness

Delayed onset muscle soreness (DOMS) refers to the muscular pain and swelling that follows unaccustomed exertion. Clinical presentation Patients may have an ache in affected muscles with reduced strength 4. Pathology DOMS is thought to occur from reversible microstructural muscle injury that...
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Deltoid ligament injury

Deltoid ligament injuries involve the deltoid ligament that forms the medial part of the ankle joint. It attaches the medial malleolus to multiple tarsal bones. Pathology Mechanism of injury It occurs due to eversion and/or pronation injury, or can be associated with lateral ankle fractures. ...
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Deltoid ligament of the ankle

The deltoid ligament or medial collateral ligament of the ankle forms the medial part of the ankle joint. It attaches the medial malleolus to multiple tarsal bones.  Gross anatomy The ligament is composed of two layers. The superficial layer has variable attachments and crosses two joints whil...
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Deltoid muscle

The deltoid muscle is the largest of the shoulder muscles. The muscle is composed of three heads (clavicular, acromial and spinous), although electromyography suggests that there are at least seven control regions that could act independently 1. Summary origin: lateral 1/3 of the clavicle, acr...
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Denervation changes in muscles

Denervation changes in muscles can be observed in a number of settings. Radiographic features MRI in the very early stage, muscle signal may be normal earliest change is increased T2 signal (best seen on a fat saturated T2WI such as STIR) chronic changes are marked by muscle atrophy and fat...
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Dense metaphyseal bands (differential)

The differential diagnosis of dense metaphyseal bands is wide. Differential diagnosis Common chronic anaemia, e.g. sickle cell disease, thalassemia chemotherapy, e.g. methotrexate growth acceleration lines following growth arrest due to systemic illness or stress in infancy or childhood, e....
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Depressed skull fracture

Depressed skull fractures result in the bone of the skull vault being folded (depressed) inward into the cerebral parenchyma. It is usually the result of a high energy impact to the skull. Pathology These mostly (~75%) occur in the frontoparietal region 3. Associations There are number of as...
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De Quervain tenosynovitis

De Quervain tenosynovitis, also known as washerwoman's sprain/strain, is a painful stenosing tenosynovitis involving the first extensor (dorsal) tendon compartment of the wrist (typically at the radial styloid). This compartment contains the abductor pollicis longus (APL) and extensor pollicis b...
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Dercum disease

Dercum disease, also known as adiposis dolorosa, is a rare disorder of subcutaneous tissue characterised by multiple painful lipomas. Epidemiology Although the exact incidence is unclear, Dercum disease affects women more than men 1,2. It is usually sporadic, however, autosomal dominant forms ...
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Dermatofibrosarcoma protuberans

Dermatofibrosarcoma protuberans (DFSP) is an uncommon exophytic, slow growing, low grade, spindle cell tumour arising in the dermal and subcutaneous tissues, particularly of the trunk region with excellent outcome after complete surgical resection. Epidemiology The tumour occurs in patients of...
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Dermatographia

Dermatographia, also known as skin writing, refers to a skin condition in which skin scratches causes linear red marks. The cause is unknown, however, it is related to penicillin use and mastocytosis.
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Dermatomyositis

Dermatomyositis is an autoimmune inflammatory myositis. Epidemiology There is a recognised female predilection. It has a bimodal age of presentation depending on the variant: juvenile dermatomyositis (JDM): affects children and tends to be more severe adult dermatomyositis (ADM): typically a...
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Derotation screw

A derotational screw is an orthopaedic device used for internal fixation of fractures to, unsurprisingly, limit rotation of the fracture. They are applied across fractures at risk of rotation and hence avascular necrosis.
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Describing a fracture (an approach)

Describing a fracture is a basic requirement when making an assessment of a plain radiograph. There are many ways to approach the assessment of the radiograph; this is just one approach. I: Describe the film What film (or films) are you looking at? Check the who, what, why, when, and where. I...
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Desmoid tumour

Desmoid tumours are benign, non-inflammatory fibroblastic tumours (see WHO 2002 classification of soft tissue tumours) with a tendency for local invasion and recurrence but without metastasis. Terminology The terms desmoid tumour and aggressive fibromatosis are occasionally used synonymously b...
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Desmoplastic fibroma

Desmoplastic fibromas (DF) are extremely rare bone tumours that do not metastasize, but may be locally aggressive. They are considered to be a bony counterpart of soft tissue desmoid tumours and are histologically identical.  Clinical presentation Incidence is ~0.3%. The most common areas of i...
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Developmental dysplasia of the hip

Developmental dysplasia of the hip (DDH) denotes aberrant development of the hip joint and results from an abnormal relationship of the femoral head to the acetabulum. There is a clear female predominance, and it usually occurs from ligamentous laxity and abnormal position in utero. Therefore, i...
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Developmental stages of the spheno-occipital synchondrosis

Developmental stages of the spheno-occipital synchondrosis take place in a number of predictable steps.  Fusion of the spheno-occipital synchondrosis was well underway by the age of 15 years and is complete by 17-18 years.  Fusion begins superiorly and progresses inferiorly. Persistence of a ...
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Diabetic myonecrosis

Diabetic myonecrosis is an uncommon complication of diabetes mellitus, occurring in patients with chronic poor glycemic control.  Epidemiology There is a slight predilection for females and patients with type 1 diabetes. The average age of presentation is 40 years.  Clinical presentation Pat...
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Diaphragmatic paralysis

Diaphragmatic paralysis can be unilateral or bilateral. Clinical presentation Clinical features are highly variable according to underlying aetiological factor: unilateral paralysis: asymptomatic in most of the patients as the other lung compensates may have dyspnoea, headaches, fatigue, ins...
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Diaphyseal lesions

Diaphyseal lesions are unsurprisingly predominantly found centred in the diaphysis.  Differential diagnosis simple bone cyst fibrous dysplasia enchondroma metastases myeloma / plasmacytoma lymphoma osteomyelitis osteoid osteoma round cell tumour, e.g. Ewing sarcoma (children) bone inf...
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Diaphyseal lesions (mnemonic)

A mnemonic for a short list of diaphyseal lesions is: CEMENT Mnemonic C: bone cysts E: enchondroma/Ewing sarcoma M: bone metastasis E: eosinophilic granuloma N: non-ossifying fibroma (NOF) T: tuberculosis/osteomyelitis
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Diaphysis

The diaphysis (pl: diaphyses) is the main portion (shaft) of a long bone (a bone that is longer than it is wide).  The diaphysis has a tubular composition with a hard outer section of hard cortical bone and central portion with cancellous bone and bone marrow cavity. It is formed by primary os...
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Diarthroses

Diarthroses are a functional class of joint that are freely mobile. All synovial joints are considered diathroses.    See also  synarthroses amphiarthroses
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Diastrophic dysplasia

Diastrophic dysplasia (DTD) is a type of short limb skeletal dysplasia (micromelic dwarfism). In adulthood patients have a stature between 100 and 140 cm. Epidemiology There may be a relatively increased prevalence in Finland ref. Pathology Larger than normal collagen fibrils have been extra...
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Die-punch fracture

A die-punch fracture results from axial loading forces on the distal radius. It is an intra-articular fracture of the lunate fossa of the distal radius. It may be depressed. See also distal radius fracture upper limb fractures
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Dietrich disease

Dietrich disease is the eponymous name given to avascular necrosis (aseptic necrosis) involving a metacarpal head. 1 Epidemiology The condition is rare and most often spontaneous but may be associated with trauma, systemic lupus erythematosus or steroid use. Any metacarpal may be affected howe...
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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...
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Differential diagnosis for metatarsal region pain

Forefoot pain in the metatarsal region is a common complaint and may be caused by a number of conditions. It is worthwhile for a radiologist to have some knowledge of the potential causes and their imaging features.1 Trauma turf toe plantar plate disruption sesamoiditis stress fracture str...
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Diffuse bone sclerosis (differential)

Diffuse bone sclerosis can result from a number of causes. They include: haematological causes myelofibrosis sickle cell disease diffuse osteosclerosing myeloma: rare mastocytosis  metabolic bone disorders hyperthyroidism hypoparathyroidism renal osteodystrophy congenital sclerosing b...
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Diffuse bony sclerosis (mnemonic)

Useful mnemonics for remembering causes of diffuse bony sclerosis include: 3 M's PROOF Regular Sex Makes Occasional Perversions Much More Pleasurable And Fantastic 1   Mnemonics 3 M's PROOF M: malignancy metastases (osteoblastic metastases) lymphoma leukaemia M: myelofibrosis M: mastoc...
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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 ...
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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...
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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.  ...
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Dinner fork deformity (wrist)

A dinner fork deformity, also known as a bayonet deformity, occurs as the result of a malunited distal radial fracture, usually a Colles fracture. The distal fragment is dorsally angulated, displaced and often also impacted. The term is descriptive, as the lateral view of the wrist is similar to...
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Disarticulation

The term disarticulation refers to the disconnection of all or part of a limb from the body, specifically through a joint. This is in contrast to amputation, which is the disconnection or removal of the structure through a bone.
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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...
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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...
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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...
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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 ass...
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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...
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Discogenic vertebral sclerosis

Discogenic vertebral sclerosis is one of the skeletal "do not touch" lesions and should not be confused with a metastatic lesion or disc space infection. It can lead to an unnecessary biopsy. Clinical presentation The typical clinical presentation is a middle-aged female with chronic low back ...
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Discoid meniscus

Discoid menisci are those that have a body that is too wide, usually affecting the lateral meniscus. They are incidentally found in 3-5% of knee MRI examinations. Epidemiology Discoid menisci condition is congenital, frequently bilateral (up to 50%) and has been reported in twins, although no ...
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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 ...
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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...
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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 ...
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Disorganised periosteal reaction

Disorganised or complex periosteal reaction has spicules with random orientation and appearance. It can be seen in highly aggressive processes: osteosarcoma metastasis osteomyelitis chondrosarcoma Ewing sarcoma stress fracture malignant fibrous histiocytoma spindle cell sarcoma See also...
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Disproportionate posterior horn sign

The disproportionate posterior horn sign is a feature described with a meniscal tear having a posteriorly flipped fragment. Pathology Bucket handle tears of meniscus of the knee joint constitute 10% of meniscal tears. They consist of a vertical or longitudinal tear (which includes vertical-obl...
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Distal appendicular skeletal metastases

Distal appendicular skeletal metastases, especially distal to the knee and elbow joints, are uncommon. Clinical presentation Localised pain and swelling, along with pathological fractures, are the most common 3.  Pathology Aetiology Malignancies that most commonly spread to appendicular ske...
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Distal clavicular erosion (differential)

Erosion or absence of the distal ends of the clavicles may be seen in a wide range of conditions. Differential diagnosis Bilateral erosions weightlifter's shoulder: due to repetitive microtrauma; classically described in weightlifters, but can affect anyone performing repetitive overhead lift...
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Distal fibula fracture (basic)

Distal fibula fractures are the most common type at the ankle and are usually the result of an inversion injury with or without rotation. They are the extension of a lateral collateral ligament injury. Background Pathophysiology Most ankle injuries occur because of an inversion injury. A pure...
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Distal intersection syndrome

The distal intersection syndrome relates to tenosynovitis of the extensor pollicis longus (EPL) tendon, where it crosses the extensor carpi radialis longus (ECRL) and brevis (ECRB) tendons 1. It is distinct from intersection syndrome which occurs more proximally in the forearm at the intersectio...
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Distal phalanx fracture

Distal phalanx fractures are common injuries that can result in an open fracture. Radiographic features The fracture is easily seen, especially when intra-articular. Carefully evaluate the soft tissues for nail injury. Treatment and prognosis The majority of distal phalanx fractures are non-...
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Distal radial fracture

Distal radial fractures are a heterogeneous group of fractures that occur at the distal radius and are the dominant fracture type at the wrist. These common fractures usually occur when significant force is applied to the distal radial metaphysis.  Epidemiology Distal radial fractures can be s...
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Distal radial fracture (summary)

Distal radial fractures are a relatively common group of injuries that usually occur following a fall. The commonest of these fractures is a transverse extra-articular fracture and where there is associated dorsal angulation, this is termed a Colles fracture. Reference article This is a summar...
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Distal radioulnar joint

The distal radioulnar joint is a pivot type synovial joint between the distal radius and ulna. Summary articulation: pivot type synovial joint between the distal aspect of the radius and the ulna movement: rotation of the distal radius ligaments: triangular ligament, and anterior and posteri...
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Distal radioulnar joint dislocation

Isolated distal radioulnar joint (DRUJ) dislocations are rare and are more commonly part of complex forearm fracture-dislocations.  Clinical presentation Wrist pain, swelling and deformity following FOOSH or direct trauma. The patient will be unable to supinate/pronate the forearm 1,2.  Patho...
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Distal tibiofibular syndesmosis

The tibiofibular syndesmosis is a complex fibrous joint composed of multiple ligaments and a broad fibrous membrane (the interosseous membrane) that spans between the tibia and fibula throughout the length of both bones. The distal osseous part of this syndesmotic joint includes the following f...
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Distal ulnar fractures

Distal ulnar fractures are common, and usually occur with a concurrent distal radius fracture. Pathology Isolated fractures occurs as a result of direct force to the ulna. Fractures associated with radius fractures usually occur as the result of a fall on an outstretched arm. Distal ulnar fra...
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Dorsal defect of the patella

Dorsal defect of the patella is a benign subchondral lesion of unknown aetiology and a normal developmental anomaly of the patella, which can be mistaken for a pathological process such as a focus of infection or osteochondritis dissecans. Epidemiology Dorsal defect of patella occurs in males ...
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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...
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Dorsal intercalated segment instability

Dorsal intercalated segment instability (DISI) is one of the types of instability involving the wrist. It occurs because of a disruption of the dorsal intercarpal ligament. It is more often encountered than volar intercalated segment instability (VISI). Pathology Aetiology wrist trauma, with ...
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Dorsal interossei (foot)

The four dorsal interossei muscles are the most superior muscles in the sole of the foot and abduct the second to fourth toes relative to the long axis through the second toe. Summary origin sides of metatarsals of toes I to V insertion extensor hoods and bases of proximal phalanges of toes...
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Dorsal interossei muscles (hand)

The interossei muscles as a group consist of four palmar (1st is often rudimentary) and four dorsal muscles. Collectively, the interossei contribute to abduction and adduction of the fingers and also contribute to flexion of the metacarpophalangeal joints (MCPJ) and extension of the interphalan...
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Dorsal scapular nerve

The dorsal scapular nerve is a branch from the C5 root of the brachial plexus and supplies the rhomboid muscles. Gross anatomy Origin Posterior aspect of the C5 root of the brachial plexus. Course It courses through scalenus medius then accompanies the dorsal scapular vessels inferiorly, de...
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Dot in a circle sign

Dot in a circle sign is an MRI sign for maduromycosis or mycetoma. It is described as a classic appearance on T2 weighted images which show a small rounded hyperintensity (representing granulation tissue), surrounded by a low signal intensity rim (representing fibrous septa) with a hypointense ...
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Double axillary pouch sign

The double axillary pouch sign is a collection of fluid between a torn anteroinferior glenoid labrum and the glenoid rim, giving the appearance of a second axillary pouch. The sign is seen best with MR arthrography on the coronal view, and is considered by some, a very specific sign for an ante...
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Double contour cartilage line

Double contour cartilage line is a sign in ultrasonography of the gout arthropathy which is characterised by an echogenic line on the outer surface of the joint cartilage parallel to the subchondral bone secondary to deposition of monosodium urate crystals on the surface of hyaline articular car...
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Double contour sign (trochlear dysplasia)

The double contour sign is a helpful radiologic sign which is seen on true lateral plain radiographs of trochlear dysplasia.  A double line at the anterior aspect of condyles that seen if medial condyle is hypoplastic. See also crossing sign of trochlear dysplasia
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Double delta sign

The double delta sign is a feature that has been described in a bucket handle meniscal tear when the inner meniscal fragment flipped anteriorly adjacent to the anterior horn of the donor site and is referred to as a displaced bucket handle tear. The original location of the posterior horn remain...
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Double density sign (osteoid osteoma)

The double density sign, also sometimes clumsily referred to as the hotter spot within hot area sign, is a bone scan sign of an osteoid osteoma. It refers to a central focus of intense uptake (the nidus) within a surrounding lower, but nonetheless increased uptake, rim. See also double densit...
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Double disc sign

Thickening of the insertion of the lateral pterygoid muscle can mimic an anterior displaced temporomandibular disc. When both thickening of the inferior belly insertion and an anteriorly displaced disc are present, the two structures parallel each other; the so-called "double disc" sign.
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Double layered patella

A double-layered patella (DLP) is a rare form of bipartite patella It is a congenital anomaly which presents with multiple fragmented patellae with smooth, well-corticated borders. A double-layered patella is considered pathognomonic for multiple epiphyseal dysplasia.1  
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Double line sign

The double line sign is an MRI finding seen at the periphery of a region of osteonecrosis (avascular necrosis, bone infarct). It is best seen on T2 weighted sequences and consists of an inner bright T2 line representing granulation tissue and an outer dark line representing sclerotic bone. This ...
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Double Oreo cookie sign (glenoid labrum)

The double Oreo cookie sign refers to the presence of two hyperintense lines in the superior glenoid labrum, one of which represents a superior labral tear and the other a physiological sublabral recess 1, 2. This pattern is likened to an Oreo cookie with two layers of (white) cream and three l...
Article

Double PCL sign

The double PCL sign appears on sagittal MRI images of the knee when a bucket-handle meniscal tear (medial meniscus in 80% of cases) flips towards the centre of the joint so that it comes to lie anteroinferior to the posterior cruciate ligament (PCL) mimicking a second smaller PCL. A double PCL ...
Article

Doughnut sign on bone scan

The doughnut sign refers to the bone scan pattern whereby there is increased uptake peripherally with a photopenic centre. This appearance may be seen in a number of cystic lesions including: aneurysmal bone cyst giant cell tumour simple bone cyst The doughnut sign is a non-specific sign, an...
Article

Dracunculiasis

Dracunculiasis (also known as guinea worm disease) is a potentially disabling infection caused by Dracunculus medinensis (meaning "little worm from Medina"). Clinical presentation The radiologic finding of a calcified guinea worm is common in endemic areas.  In the vast majority of cases (one...
Article

Dripping candle wax sign

Dripping candle wax sign, also known as flowing candle wax appearance, describes the appearance of sclerotic cortical thickening in melorheostosis. The irregular cortical hyperostosis typically occurs on one side of the involved bone and undulates along much like melted wax down a candle. Patho...
Article

Dual energy x-ray absorptiometry (DEXA)

Dual-energy x-ray absorptiometry (DEXA) is a technique used to aid in the diagnosis of osteopaenia and osteoporosis.  Radiographic features Values are calculated for the lumbar vertebrae and femur preferentially, and if one of those sites is not suitable (e.g. artifact, patient mobility, histo...
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Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is a dystrophinopathy and the most common muscular dystrophy. Epidemiology DMD has an incidence of 1 in 3500 to 5000 males 1,2. The condition is extremely rare in females due to its inheritance pattern, as discussed below 1. Clinical presentation The charact...
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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

Dupuytren contracture

A Dupuytren contracture, or palmar fibromatosis, is a fibrosing condition that characteristically presents as a firm nodularity on the palmar surface of the hand with coalescing cords of soft tissue on the webs and digits. Epidemiology It is considered the most common of the superficial fibrom...
Article

Duverney fracture

Duverney fractures are a type of pelvic fracture most commonly occurring in the setting of a direct blow to the ilium, with a resultant isolated iliac wing fracture. It is regarded as a stable injury but may be operated on in the event of severe comminution.  History and etymology It is named ...

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