Elastofibroma dorsi is a benign soft-tissue tumour with a characteristic location and imaging appearance.
It is more frequently seen in older women, with a reported female predilection of 5-13:1. The estimated mean age at diagnosis around 65-70 years.
Ectrodactyly (also known as a split hand-split foot malformation, cleft hand or lobster claw hand) is a skeletal anomaly predominantly affecting the hands (although the feet can also be affected). The condition has a highly variable severity.
The estimated incidence is at ~ 1 in 9...
Ectodermal dysplasia (ED) refers to a heterogeneous group of genetic disorders that cause abnormal ectoderm development. The effect is a non-progressive defect in the development of two or more tissues derived from embryonic ectoderm.
ED is rare with an estimated prevalence of 1:...
There are multiple handy mnemonics to recall the erector spinae muscles. They usually describe the position from lateral to medial.
I Like Standing
I Love Sex
I Long for Spinach
I Like Siri
A mnemonic to remember the main differential diagnoses for benign lytic bone lesions in patients under 30 years of age is:
S: Simple bone cyst
A: Aneurysmal bone cyst
N: Non-ossifying fibroma
E: Eosinophilic granuloma
The other differentials i...
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.
It is considered the most common of the superficial fibrom...
Chondrosarcomas of the base of the skull are rare compared with other skull base tumours but are an important differential diagnosis as surgical resection and management are affected by the preoperative diagnosis.
Chondrosarcomas of the base of the skull make up only a small fract...
e (LSTV) are a relatively common variant and can be seen in ~25% (range 15-35%) of the general population 1-3. Non-recognition of this variant and/or poor description in the report can lead to operations or procedures performed at the wrong level.
Depending on the number of thoracic vertebrae,...
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 ...
Dracunculiasis (also known as guinea worm disease) is a potentially disabling infection caused by Dracunculus medinensis (meaning "little worm from Medina").
The radiologic finding of a calcified guinea worm is common in endemic areas.
In the vast majority of cases (one...
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...
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 ...
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.
The typical clinical presentation is a middle-aged female with chronic low back ...
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.
The terms desmoid tumour and aggressive fibromatosis are occasionally used synonymously b...
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)
extends above or below the disc level (into the suprapedicular or infrapedicular zone)
Disc extrusions are a...
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 ...
Diaphragmatic eventration refers to an abnormal contour of the diaphragmatic dome. It typically affects only a segment of the hemidiaphragm, compared to paralysis/weakness where the entire hemidiaphragm is typically affected.
Diaphragmatic eventration is congenital in nature and due...
Desmoplastic fibromas are extremely rare bone tumours that do not metastasise but may be locally aggressive. They are considered to be a bony counterpart of soft tissue desmoid tumours and are histologically identical.
Incidence is ~0.3%. The most common areas of involve...
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...
Delayed onset muscle soreness (DOMS) refers to the muscular pain and swelling that follows unaccustomed exertion.
Patients may have an ache in affected muscles with reduced strength 4.
DOMS is thought to occur from reversible microstructural muscle injury that...
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...
Reverse total shoulder arthroplasty (RTSA) is a type of total shoulder replacement. It is often the preferred method when there has been advanced damage to the rotator cuff as seen in rotator cuff arthropathy.
The reverse total shoulder flips the normal mechanical arrangement of the ...
This page lists examples of normal imaging of the lower limb, divided by region and modality.
example 1: frontal
example 2: frontal (young adult)
example 3: paediatric
example 4: paediatric (9/12, 11/12 and older child)
example 5: trauma supine
Van Buchem disease (VBD) is an extremely rare hereditary sclerosing bone dysplasia, also known as hyperostosis corticalis generalisata. This disease is characterised most notably by mandibular enlargement and thickening of the skull.
Less than 30 cases have been reported in the li...
Vertebral haemangiomas are the most common benign vertebral neoplasms. They are usually asymptomatic and incidentally detected due to their characteristic features on imaging for other reasons.
Please refer on the article on primary intraosseous haemangioma for a general discussion in this enti...
Vertebral metastases represent the secondary involvement of the vertebral spine by haematogenously-disseminated metastatic cells. They must be included in any differential diagnosis of a bone lesion in a patient older 40 years.
This article will focus only on the metastasis involving the bony s...
Vertebral pneumatocysts refers to the presence of a gas-filled cavity within the vertebrae, more prevalent on the cervical spine. Intraosseous pneumatocysts are more common adjacent to the sacroiliac joint while it is rare in the vertebral column. Other causes of vertebral gas e.g. Kümmell disea...
A Wagstaffe-Le Forte fracture refers to an avulsion fracture of the medial aspect of the distal fibula due to avulsion of the anterior tibiofibular ligament attachment.
lower extremity fractures
Widening of diploic space refers to expansion of the spongy or cancellous bone between the inner and outer tables of the calavarium. The diploic space is the medullary cavity of the skull, and a location of normal physiologic hematopoiesis in adults. Thus, expansion of this structure most common...
Wilson disease, also known as hepatolenticular degeneration, is a multisystem disease, which rarely has musculoskeletal manifestations secondary to the accumulation of copper in the articular cartilage.
Reported manifestations include 1-3
Wind-swept pelvis fracture is a combination a unilateral AP compression (open book) injury with a contralateral lateral compression injury.
It occurs when the internal rotation of one iliac wing causes a unilateral sacral compression fracture, while the same forces cause external rotation of t...
Wrisberg rips are longitudinal vertical meniscal tears. They occur at the at the junction of the ligament of Wrisberg and the posterior horn of the lateral meniscus, and are commonly associated with anterior cruciate ligament tears 1.
The Z deformity is one of the musculoskeletal manifestation of rheumatoid arthritis in hand:
radial deviation at the wrist
ulnar deviation of the digits, and often
palmar subluxation of the proximal phalanges
Cysticercosis is a parasitic tissue infection caused by ingestion of tapeworm eggs through a fecal-oral transmission or auto-infection. Humans act as a definitive host in this disease.
CNS manifestations are discussed individually on neurocysticercosis.
The disease is endemic in ...
Cystic adventitial disease (CAD) is an uncommon vascular pathology predominantly affecting peripheral vessels. The vast majority of cases occur in arteries with venous involvement being an even extremely rare occurrence 8.
It typically affects young to middle-aged individuals with...
The cyclops lesion, also known as localised anterior arthrofibrosis, is a painful anterior knee mass that arises as a complication of anterior cruciate ligament (ACL) reconstruction.
Cyclops lesions occur with an estimated frequency of ~5% (range 1-9.8%) of patients following ACL ...
Cutis laxa is a rare dermatological condition, characterised elastic fibre loss resulting in patients with very lax skin. Patients can also develop emphysema.
Cutis laxa may be inherited (autosomal dominant, autosomal recessive, or X-linked recessive) or may occur sporadically.
The critical zone of the rotator cuff is an area approximately 8-15 mm from the insertion of the rotator cuff tendons onto the greater tubercle of the humeral head, mainly within the supraspinatus tendon. This is a watershed zone between the anterior and posterior circumflex humeral, thoracoacro...
Craniosynostosis refers to premature closure of the cranial sutures. The skull shape then undergoes characteristic changes depending on which suture(s) close early.
There is a 3:1 male predominance.
Primary forms are either sporadic or familial. Secondary craniosynosto...
Craniofacial fibrous dysplasia is one of four types of fibrous dysplasia and is characterised, as the name suggests, by involvement of the skull and facial bones.
For a general discussion of the underlying pathology, refer to the parent article fibrous dysplasia.
Although the term...
Cortical desmoids, also known as cortical avulsive injuries or the Bufkin lesion, are a benign self-limiting entity. This is a classic "do not touch" lesion, and should not be confused with an aggressive cortical/periosteal process (e.g. osteosarcoma).
Cortical desmoid is a misnom...
Coracoclavicular (CC) ligament injury is common with shoulder trauma. It is considered part of the spectrum of acromioclavicular joint injuries 2 and is not often an isolated injury. It is also often injured with clavicular fractures.
This injury is easy to miss, especially with presence of an...
Conus medullaris syndrome is caused by an injury or insult to the conus medullaris and lumbar nerve roots. It is a clinical subset of spinal cord injury syndromes. Injuries at the level of T12 to L2 vertebrae are most likely to result in conus medullaris syndrome.
The conus medullari...
Congenital talipes equinovarus (CTEV) is considered the most common anomaly affecting the feet diagnosed on antenatal ultrasound.
While some use CTEV and club foot (CF) synonymously, in certain publications term clubfoot is considered a more general descriptive term that describes ...
Congenital radial head dislocation is the most common congenital elbow abnormality. It can occur in isolation, or more commonly may be associated with other conditions or syndromes.
Overall, congenital radial head dislocation is rare 2.
Congenital radial he...
Duchenne muscular dystrophy (DMD) is a dystrophinopathy and the most common muscular dystrophy.
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.
Congenital pseudoarthrosis of the clavicle is a rare condition, which typically presents as an isolated anatomical variant.
Usually presents as a midclavicular swelling in the neonate or young child 1.
Congenital pseudoarthrosis of the clavicle is more commo...
Congenital insensitivity to pain (CIP) refers to group of rare hereditary sensory and autonomic neuropathies (HSANs) characterised by an inability to feel pain 1.
Although not clearly defined in the literature, CIP is not one specific diagnosis, but describes symptoms common to man...
Complex meniscal tears extend in more than one plane, and can in turn create separate flaps of meniscus.
The mensical tear usually includes a combination of radial, horizontal, and longitudinal components (any two or all three). Often the meniscus substance app...
Coccidioidomycosis refers to an infection caused by the dimorphic fungus Coccidioides spp, usually localised to the lungs. This disease is not to be confused with the similarly named paracoccidioidomycosis.
The most common forms of Coccidioides spp are Coccidioides immitis and Coc...
Becker muscular dystrophy (BMD) is a dystrophinopathy that is considered to be a milder form of Duchenne muscular dystrophy.
It may be present in 3 to 6 per 100,000 male births. The condition is extremely rare in females due to its inheritance pattern, as discussed below.
Perched facet joint is a vertebral facet joint whose inferior articular process appears to sit 'perched' on the ipsilateral superior articular process of the vertebra below.
Any further anterior subluxation will result in dislocation, with one facet "jumping" over the other and becoming locked ...
Congenital lumbar spinal stenosis (CLSS) is a type of vertebral central canal stenosis and has a different epidemiology with less severe degenerative change compared to acquired/degenerative lumbar spinal stenosis.
CLSS tends to affect patients at a younger age (30-50 years old) ...
Congenital muscular dystrophies (CMD) are a heterogeneous group of autosomal recessive myopathies presenting at birth with hypotonia, delayed motor development, and early onset of progressive muscle weakness, confirmed with a dystrophic pattern on muscle biopsy.
Clasp-knife deformity is relatively common congenital anomaly found at the lumbosacral junction.
When a clasp-knife deformity is accompanied by pain on extension secondary to protrusion of the enlarged spinous process (knife blade) into the sacral spinal canal, it is called clasp-k...
Accessory sacroiliac joints are a common finding, present on ~15% (range 13-17.5%) of CT studies, and may be unilateral or bilateral. They are an articulation between the medial aspect of the posterior superior iliac spine and the sacrum just lateral to the second dorsal sacral foramen. They may...
Uncovertebral joints, also called Luschka’s joints, are seen bilaterally between adjacent cervical vertebrae, identified by the cat ear shaped uncinate processes of the C3-7 vertebrae (C1 and C2 have no uncinate processes).
The articulation forms between the uncina...
Chronic hip subluxation most common occurs in paediatric patients with neuromuscular disorders (e.g. cerebral palsy). It is considered a form of developmental hip dysplasia.
Chronic hip subluxation occurs in ~45% of cerebral palsy patients who are not walking by 5 years of age 3....
Cavernous venous malformation, also traditionally referred to as a cavernous haemangioma (despite it not being a tumour) or cavernomas, are non-neoplastic slow flow venous malformations found in many parts of the body.
Despite the ubiquity of use of the traditional terms cavernoma...
Charcot joint, also known as a neuropathic or neurotrophic joint, refers to a progressive degenerative/destructive joint disorder in patients with abnormal pain sensation and proprioception.
In modern Western societies by far the most common cause of Charcot joints is diabetes, an...
Chondromyxoid fibromas (CMFs) are extremely rare, benign cartilaginous neoplasms that account for <1% of all bone tumours.
The majority of cases occur in the second and third decades, with ~75% of cases occurring before the age of 30 years 1,12-15. There is no recognised gender ...
Chondromalacia patellae refers to softening and degeneration of the articular hyaline cartilage of the patella and is a frequent cause of anterior knee pain.
Tends to occur in young adults. There is a recognised female predilection.
Patients with chondromal...
Chondrolysis, also known as acute cartilage necrosis, is an acute cartilage destruction of the femoral head. It is one of the complications that are specifically associated with slipped capital femoral epiphysis (SCFE). It is a poorly understood phenomenon.
The quoted incidence is...
Chondroid lipomas are rare benign soft tissue tumours that, as you might guess, contain a varied ratio of both fat and cartilage. These lesions can be diagnostically confusing as they may mimic or be confused with other fat containing neoplasms, most importantly those of much greater clinical si...
Chondrodysplasia punctata (CDP) is a collective name for a heterogenous group of skeletal dysplasias. Calcific stippling of cartilage and peri-articular soft tissues is often a common feature.
It can be broadly divided into rhizomelic and non-rhizomelic forms:
Chondroblastomas, also referred as Codman tumours, are rare benign cartilaginous neoplasms that characteristically arise in the epiphysis or apophysis of a long bone in young patients. Despite being rare, they are one of the most frequently encountered benign epiphyseal neoplasms in skeletally i...
A floating pillar, also referred as pedicolaminar fracture-separation injury, is characterised by fractures through the pedicle and lamina of a cervical spine vertebrae creating a free-floating articular pillar fragment. It is an unstable cervical spine fracture that results from hyperflexion–la...
Cervical canal stenosis can be acquired (e.g. trauma, discs, and ossification of the posterior longitudinal ligament) or congenital. It refers to narrowing of the spinal canal, nerve root canals, or intervertebral foramina of the cervical spine.
normal AP diameter is ~17 ...
The carpal boss is an unmovable hypertrophied bony protuberance at the base of the second or third metacarpals on the dorsal surface, near the capitate and trapezium.
The condition may represent either or a combination of:
degenerative osteophyte formation
os styloideum (an access...
Calcium pyrophosphate dihydrate disease (CPPD disease), also referred as pyrophosphate arthropathy and perhaps confusingly as pseudogout, is common, especially in the elderly, and is characterised by the deposition of calcium pyrophosphate in soft tissues and cartilage.
CPPD is on...
Camptocormia (bent spine syndrome) is a rare syndrome characterised by involuntary flexion of the thoracolumbar spine with weight-bearing which reduces when laying down, and is due to isolated atrophy of the paraspinal muscles.
This condition may be associated
Parkinson disease: ...
Calcific bursitis is the result of deposition calcium hydroxyapatite crystals. It is closely related to calcific tendinitis, and many authors refer to them as being the same condition.
Caisson disease is an uncommon diving-related decompression illness that is an acute neurological emergency typically occurring in deep sea divers.
Diving-related decompression illness is classified into two main categories 3:
Arterial gas embolism secondary to pulmonary decompression barotra...
Café au lait spots are a type of pigmented skin lesions which are classically described as being light brown in colour.
Conditions associated with them include:
neurofibromatosis type 1 (NF1)
McCune-Albright syndrome: typically irregular which has been likened to ...
The orthogonal projection (or view) is, by definition, a radiographic projection obtained 90 degrees to the original view. It forms the basic requirements of a 'radiographic series', that being 'two orthogonal projections of the region of interest'
Cases can appear normal in one...
The sacroiliac (SI) joint is a synovial and fibrous joint between ilium and the sacrum. It has little movement and its main function is to transfer weight between the axial and lower appendicular skeletons. The SI joint is a symmetrical joint (i.e. is paired) with an oblique coronal orientation ...
Spontaneous osteonecrosis of the knee, also known as Ahlback disease, SONK or even SPONK, has similar appearances to osteochondritis dissecans of the knee but is found in an older age group.
SONK is seen more frequently in women (M:F 1:3) and affects older patients, typically over...
Rectus sheath haematomas, as the term implies, occur when a haematoma forms in the rectus abdominis muscle / rectus sheath. It is most common in its lower segment and is generally self-limiting.
Rectus sheath haematomas are more common in women with a 3:1 F:M ratio.
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 recognised microscopically by alterations in the cytoplasm (becomes eosinophilic) and in the nucleus (swelling, py...
Gunshot injuries often require imaging assessment, and this evaluation has both clinical relevance (assessment of organ damage, surgical planning and prognostication), and often also forensic implications.
Incidence of gunshot injuries to the head is increasing in some countries, ...
Bursitis is inflammation of abursa, 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 ...
Brodie abscess is an intraosseous abscess related to a focus of subacute pyogenic osteomyelitis. Unfortunately, there is no reliable way radiographically to exclude a focus of osteomyelitis. It has a protean radiographic appearance and can occur at any location and in a patient of any age. It mi...
Brachymetatarsia (a.k.a. congenital short metatarsus) is a rare condition that develops from early closure of the growth plate.
Females are almost exclusively affected 1.
It typically involves the fourth ray or, less frequently, more than one metatarsal bon...
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.
Trauma, usually by motor vehicle accidents, involves severe traction on the ...
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.
A botryoid rhabdomyosarcoma is a type of embryonal rhabdomyosarcoma and accounts for 5-10% of all rhabdomyosarcomas 6.
It tends to occur in paediatric population, often between birth and 15 years of age 7.
Rhabdomyosarcomas generally have a nonspecific infiltrative ap...
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...
Conditions associated with bone deformity from softening includes:
bowing of long bones
biconcave vertebral bodies / codfish vertebra
Blount disease refers to a local disturbance of growth of the medial proximal tibial epiphysis that results in tibia vara. The condition is commonly bilateral.
There is no recognised inheritance pattern.
Clinically, the child often presents with leg bowin...
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.
There is extreme chromosomal fragi...
Bizarre parosteal osteochondromatous proliferation (BPOP) (also known as a Nora lesion) is a benign exophytic osteochondral lesion which has an appearance similar to an osteochondroma, and is typically seen in the hands and feet.
BPOPs are continuous with the underlying cortex, but usually wit...
Biceps chondromalacia is an attritional lesion of the humeral head caused by repeated abrasion by the intra-articular segment of the long head of biceps tendon.
The long head of biceps brachii arises from the supraglenoid tubercle of the glenoid fossa and has an intra- and extra-arti...
Bisphosphonate-related proximal femoral fractures are an example of insufficiency fractures, although the direct causative link remains somewhat controversial 2.
The atypical fracture pattern occurs in the proximal third of the femur, typically subtrochanteric, and may be unilateral or bilatera...