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Apophysis

The apophyses (singular: apophysis) are the normal bony outgrowths that arise from separate ossification centers and eventually fuse with the bone in time. The apophysis is a site of tendon or ligament attachment, as compared to the epiphysis which contributes to a joint. When unfused, they can...

Apophysis of the proximal 5th metatarsal

The apophysis of the proximal 5th metatarsal lies laterally and is oriented longitudinally parallel to the shaft. Apophysis of the fifth metatarsal base appears on plain radiographs at age 12 for boys and 10 for girls. Fusion of the apophysis to the metatarsal base usually occurs within the fol...

Appendicular films (early clinical)

This is a basic article for medical students and other non-radiologists Appendicular films are x-rays taken of the bones and joints of the arms and legs. I've used this term to separate the x-rays taken as part of an assessment of non-acute disease from trauma films which represent x-rays taken...

Appendicular skeleton

The appendicular skeleton is the portion of the bony skeleton that includes and supports the limbs (the appendages). It includes the pectoral girdle and the bony pelvis, connected to the axial skeleton centrally and is composed of 126 bones in total. Appendicular bones form from cartilage, by ...

Apple core sign (femur)

The apple core sign has been used to describe the circumferential erosion of the femoral neck seen in synovial chondromatosis. Although this is the most common process that may lead to an apple core erosion of the femoral neck, this has also been observed with: pigmented villonodular synovitis ...

Arcade of Frohse

The arcade of Frohse (pronounced "\ Frəʊs \" to rhyme with "crows") is also known as the supinator arch. The arcade is formed by a fibrous band between the two heads of the supinator muscle. The deep branch of the radial nerve passes beneath the arcade accompanied by vessels known as the leash ...

Arcuate foramen

The arcuate foramen (foramen arcuale atlantis, ponticulus posticus or posterior ponticle, or Kimerle anomaly) is a frequently encountered normal variant of the atlas and is easily appreciated on a lateral plain film of the cranio-cervical junction. It develops by calcification of the posterior ...

Arcuate ligament

The arcuate ligament is part of the posterolateral ligamentous complex of the knee that is variably present, being found in ~65% (range 47.9-71%) of knees. It is a Y-shaped thickening of the posterolateral capsule, which arises from the fibular styloid and divides into two limbs: medial limb: c...

Arcuate line

The arcuate line is located at roughly one-third of the distance from the pubic crest to the umbilicus. It is the demarcation where the internal oblique and transversus abdominis aponeuroses of the rectus sheath start to pass anteriorly to the rectus abdominis muscle, leaving only the transversa...

Arcuate sign (knee)

The arcuate sign is often a subtle but important finding on knee x-rays and represents an avulsion fracture of the proximal fibula at the site of insertion of the arcuate ligament complex, and is usually associated with cruciate ligament injury (~90% of cases) 2. The fracture fragment is attache...

Arm

The arm is part of the upper limb below the pectoral girdle and above the forearm, comprising the humerus. The elbow joint is inferior and the glenohumeral joint is superior. Arm flexion, extension, abduction, adduction, internal rotation and external rotation occur at the shoulder. See humer...

Arnold-Hilgartner classification of haemophilic arthropathy

Arnold-Hilgartner classification is a plain radiograph grading system for haemophilic arthropathy of the knee 1,2: stage 0: normal joint stage I: no skeletal abnormalities, soft-tissue swelling is present stage II: osteoporosis and overgrowth of the epiphysis, no cysts, no narrowing of the ca...

Arrested pneumatisation of the skull base

Arrested pneumatisation of the skull base is an anatomical variant that most commonly occurs in association with the sphenoid sinus. It is known that the sphenoid bones undergo early fatty marrow conversion antecedent to normal pneumatisation. However, for unclear reasons, some individuals exper...

Arthrofibrosis

Arthrofibrosis is a complication of injury or trauma to a joint. It can also be iatrogenic e.g. post knee surgeries. It consists of excessive scar tissue formation within the joint capsule, resulting in pain, stiffness, and swelling, that are greater than expected in the given clinical scenario....

Arthrogryposis

Arthrogryposis (multiplex congenita) is a clinical or imaging descriptor that denotes congenital non-progressive joint contractures involving two or more body regions. Epidemiology It is thought to occur in approximately 1:3000-10,000 live births 6,8. Pathology It can result from a number o...

Articular cartilage calcification (mnemonic)

An easy to remember mnemonic for the causes of articular cartilage calcification is: HOGWASH Mnemonic H: hyperparathyroidism O: ochronosis G: gout W: Wilson disease A: arthritis S: pseudogout H: hemochromatosis

Articularis cubiti

The articularis cubiti is a muscle in the posterior compartment of the arm: origin: posterior surface of the distal humerus insertion: posterior surface of the elbow joint capsule innervation: radial nerve action: tenses the posterior elbow joint capsule during elbow extension

Articularis genu muscle

The articularis genu is a small flat muscle of the anterior knee. During knee extension it acts to tighten the synovial membrane superiorly thereby preventing impingement of the synovial folds between the femur and the patella. Summary origin: anterior distal femoral shaft insertion: knee joi...

Aseptic loosening of hip joint replacements

Aseptic loosening is considered relatively common complication of hip joint replacements. It is usually considered a long-term complication and is often considered as the most common complication 3. Pathology Aseptic loosening can occur as a result of inadequate initial fixation, mechanical lo...

ASIA impairment scale for spinal injury

The American Spinal Injury Association (ASIA) was developed by the American Spinal Injury Association in 2006, and at the time of writing (July 2016), remains the most widely used scale. This scale is part of the ASIA spinal cord injury classification. It divides spinal cord injuries into 5 cat...

Asphyxiating thoracic dysplasia

Asphyxiating thoracic dysplasia, also known as Jeune syndrome, is a type of rare short limb skeletal dysplasia, which is primarily characterized by a constricted long narrow thoracic cavity, cystic renal dysplasia and characteristic skeletal features. It is also sometimes classified as one of th...

Atelosteogenesis

Atelosteogenesis (AO) refers to a group of lethal skeletal dysplasias. Pathology Sub types atelosteogenesis type I atelosteogenesis type II atelosteogenesis type III 4

Athletic pubalgia

Athletic pubalgia refers to pain around the pubic symphysis and can have different causes, including what has become known as sports hernia or sportman's hernia and osteitis pubis. Athletic pubalgia is a clinical syndrome of chronic lower pelvic and groin pain, usually encountered in athletes. ...

Atlanto-axial subluxation

Atlanto-axial subluxation is a disorder of C1-C2 causing impairment in rotation of the neck. The anterior facet of C1 is fixed on the facet of C2. It may be associated with dislocation of the lateral mass of C1 on C2. Pathology Etiology congenital os odontoideum Down syndrome (20%) Morquio...

Atlanto-occipital assimilation

Atlanto-occipital assimilation is the fusion of the atlas (C1) to the occiput and is one of the transitional vertebrae. Epidemiology Atlanto-occipital assimilation occurs in approximately 0.5% (range 0.25-1%) of the population 2-4. Clinical presentation It is typically asymptomatic but sym...

Atlanto-occipital dissociation injuries

Atlanto-occipital dissociation injuries are severe and include both atlanto-occipital dislocations and atlanto-occipital subluxations. Pathology The tectorial membrane and alar ligaments provide most of the stability to the atlanto-occipital joint, and injury to these ligaments results in inst...

Atlas (C1)

The atlas is the first cervical vertebra, commonly called C1. It is an atypical cervical vertebra with unique features. It articulates with the dens of the axis and the occiput, respectively allowing rotation of the head, and flexion, extension and lateral flexion of the head. Unlike the rest o...

Atraumatic fracture

Atraumatic fractures, as the name suggests, occur with no trauma or minimal trauma that would not normally be expected to result in a fracture 1. They can be: stress fractures fatigue fracture insufficiency fracture atypical fractures, e.g. bisphosphonate-related proximal femoral fractures ...

Atypical cervical vertebrae

Of the cervical vertebrae, the atlas (C1), axis (C2) and vertebra prominens (C7) are considered atypical cervical vertebrae. The atlas (C1) lacks a body or spinous process. It has an anterior and posterior arches with lateral masses. Its superior articular surfaces articulate with the occiput a...

Atypical femoral fracture

Atypical femoral fracture also known as 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 femur shaft and may be unilateral or bilateral. ...

Atypical fibroxanthoma

Atypical fibroxanthomas are well-circumscribed mesenchymal skin tumors that mainly manifest in the head and neck Epidemiology Atypical fibroxanthomas are rapidly growing tumors associated with excessive sun exposure, i.e. UV exposure, and usually occur in elderly patients. There is also an ass...

Atypical lumbar vertebrae

Of the five lumbar vertebrae, L5 is considered atypical due to its shape. The remaining lumbar vertebrae are largely typical. For a basic anatomic description of the structure a generic vertebra, see vertebrae.

Atypical ribs

Owing to their features, the first, eleventh and twelfth ribs are considered atypical ribs. Of all ribs, the first is the strongest, broadest and most curved. Ribs eleven and twelve are unique, among other reasons, by not being attached to the sternum.

Atypical thoracic vertebrae

T1 and T9 - T12 are considered atypical thoracic vertebrae. T1 bears some resemblance to low cervical vertebrae. T9 has no inferior demifacet. T10 often, but not always, shares features with T11 and T12. For a basic anatomic description of the structure a generic vertebra, see vertebrae.

Autosomal dominant osteopetrosis

Autosomal dominant osteopetrosis is the less severe type of osteopetrosis and should be considered and compared with the other subtype autosomal recessive osteopetrosis. The autosomal dominant (AD) type is less severe than its autosomal recessive (AR) mate. Hence, it is also given the name "beni...

Autosomal recessive osteopetrosis

Infantile autosomal recessive osteopetrosis is a subtype of osteopetrosis, a bone disease of dysfunctional osteoclasts that results in the overgrowth of bone. It is a more severe form that tends to present earlier. Hence, it is referred to as "infantile" and "malignant" compared to its autosomal...

Avascular necrosis

Avascular necrosis (AVN), or more correctly osteonecrosis, is a generic term referring to the ischemic death of the constituents of bone. AVN has a wide variety of causes and can affect nearly any bone in the body. Most sites of involvement have an eponym associated with avascular necrosis of th...

Avascular necrosis causes (mnemonic)

Mnemonics for the causes of avascular necrosis (AVN) or more correctly osteonecrosis: STARS PLASTIC RAGS ASEPTIC Mnemonics STARS Most common causes: S: steroids T: trauma (e.g. femoral neck fracture, hip dislocation, scaphoid fracture, slipped capital femoral epiphysis 2) A: alcohol abu...

Avascular necrosis of the hip

Avascular necrosis of the hip is more common than other sites, presumably due to a combination of precarious blood supply and high loading when standing. Clinical presentation The most common presenting symptom is a pain in the region of affected hip, thigh, groin, and buttock. Although few p...

Aviator astragalus

Aviator astragalus is an antiquated reference to a pattern of isolated fracture/dislocation injury of the talus. Fractures included under this name include compression fractures of the talar neck, fractures of the body, posterior process or fracture dislocation injuries. The talar neck is the mo...

Aviator fracture

An aviator fracture is a coronal-plane fracture of the neck of the talus resulting from forced dorsiflexion of ankle. It is the second most common talar fracture, after talar dome fractures. In 20% of cases a fracture of the medial malleolus is also present 1. These fractures are at risk of av...

Avulsion fracture of the 5th metatarsal styloid

Avulsion fracture of the 5th metatarsal styloid, also known as a pseudo-Jones fracture or a dancer fracture, is one of the more common foot avulsion injuries and accounts for over 90% of fractures of the base of the 5th metatarsal. Despite what should be a simple entity, controversy exists, as ...

Avulsion fractures of the knee

Avulsion fractures of the knee are numerous due to the many ligaments and tendons inserting around this joint. They include 1: anterior cruciate ligament avulsion fracture posterior cruciate ligament avulsion fracture avulsion of the medial collateral ligament origin of MCL avulsion fracture...

Avulsion injuries

Avulsion injuries or fractures occur where the joint capsule, ligament, tendon or muscle attachment site is pulled off from the bone, usually taking a fragment of cortical bone. There are numerous sites at which these occur. Being familiar with them is important as subacute/chronic injuries can ...

Axial skeleton

The axial skeleton is the central portion of the bony skeleton comprising the head, neck and trunk (80 bones in total). It has many functions including housing and protecting the central nervous system as well as the organs of the chest, abdomen and pelvis. It enables movement and supports the u...

Axilla

The axilla is a space located between the upper limb and the neck and thorax, which permits the passage of the major neurovascular structures. Gross anatomy The axilla is pyramidal in shape with its apex opening superiorly into the base of the neck between the subclavius muscle, first rib and ...

Axillary nerve

The axillary nerve is one of five terminal branches of the brachial plexus, supplying motor and sensory branches to the shoulder. Summary origin: posterior cord of the brachial plexus course: passes out of axilla through the quadrangular space to the upper arm major branches: superior later...

Axis (C2)

The axis is the second cervical vertebra, commonly called C2. It is an atypical cervical vertebra with unique features and important relations that make it easily recognisable. Its most prominent feature is the odontoid process, which is embryologically the body of the atlas (C1) 1,2. It plays a...

Baastrup syndrome

Baastrup syndrome (also referred to as kissing spines) results from adjacent spinous processes in the lumbar spine rubbing against each other and resulting in hypertrophy and sclerosis with focal midline pain and tenderness relieved by flexion and aggravated by extension. Epidemiology It tend...

Babcock triangle

Babcock triangle is a relatively radiolucent triangular area seen in the subcapital region of the femoral neck on an anteroposterior radiograph of the hip. In this region, the trabeculae are loosely arranged and surrounded by more radiodense normal bony trabeculae groups. It may be the initial s...

Bacillary angiomatosis

Bacillary angiomatosis is an infective complication in those with the acquired immunodeficiency syndrome (AIDS) 3. Amongst other widespread multi-organ manifestations, the infection causes skin lesions which can be similar to those of Kaposi sarcoma. Pathology Characterized by a non-neoplastic...

Bado classification of Monteggia fracture-dislocations

The Bado classification is one of the more widely used classifications for Monteggia fracture-dislocations and mainly focuses on the radial component. Four types are recognised and are generally based on the principle that the direction in which the apex of the ulnar fracture points is the same ...

Baker cyst

Baker cysts, or popliteal cysts, are fluid-filled distended synovial-lined lesions arising in the popliteal fossa between the medial head of the gastrocnemius and the semimembranosus tendons via a communication with the knee joint. They are usually located at or below the joint line. They repre...

Ball and socket ankle joint

A ball and socket ankle joint is a variant affecting the ankle where there is a rounded or spherical configuration to the talar dome with the corresponding concavity of the tibial plafond. The distal fibula may or may not be involved. Pathology The etiology has been debated with two theories p...

Ball and socket joint

Ball and socket joints are a type of synovial joint where the spheroid articular surface of one bone sits within a cup-like depression of another bone. Movements The ball and socket configuration allows for movement with 3 degrees of freedom, which is more than any other type of synovial joint...

Bamboo spine

Bamboo spine is a radiographic feature seen in ankylosing spondylitis that occurs as a result of vertebral body fusion by marginal syndesmophytes. It is often accompanied by fusion of the posterior vertebral elements as well. A bamboo spine typically involves the thoracolumbar and/or lumbosacr...

Banana fracture

A banana fracture refers to a complete, horizontally oriented pathological fracture seen in deformed bones affected by Paget disease. This term is often used to describe incremental fractures that occur in Paget disease as well, which represent a type of insufficiency fracture. The former of th...

Bankart lesion

Bankart lesions are injuries specifically at the anteroinferior aspect of the glenoid labral complex, and represent a common complication of anterior shoulder dislocation. They are frequently seen in association with a Hill-Sachs lesion. Terminology Strictly speaking, a "Bankart lesion" refer...

Bannayan–Riley–Ruvalcaba syndrome

Bannayan–Riley–Ruvalcaba syndrome (BRRS or BRR syndrome) is a very rare autosomal dominant hamartomatous disorder caused by a mutation in the PTEN gene. It is considered in the family of hamartomatous polyposis syndrome. There are no formal diagnostic criteria for this disease, but characterist...

Bannayan-Zonana syndrome

Bannayan-Zonana syndrome is a rare hamartomatous disorder. Epidemiology Inheritance is by autosomal dominant transmission with few reported sporadic cases. Male predominance is reported. 1 Presentation Bannayan-Zonana syndrome characterized by : macrocephaly multiple lipomas hemangioma...

Barton fracture

Barton fractures are fractures of the distal radius. It is also sometimes termed the dorsal type Barton fracture to distinguish it from the volar type or reverse Barton fracture. Barton fractures extend through the dorsal aspect to the articular surface but not to the volar aspect. Therefore, i...

Base of the skull

The base of the skull (or skull base) forms the floor of the cranial cavity and separates the brain from the structures of the neck and face. Gross anatomy The base of the skull is a bony diaphragm composed of a number of bones - from anterior to posterior: frontal bone ethmoid bone sphenoi...

Baumann angle

Baumann angle, also known as the humeral-capitellar angle, is used for the evaluation of the displacement of pediatric supracondylar humeral fractures. It is measured on a frontal radiograph, with elbow in extension. This angle is formed by the humeral axis and a straight line through the epi...

Baxter neuropathy

Baxter neuropathy is a nerve entrapment syndrome resulting from the compression of the inferior calcaneal nerve (Baxter nerve). Clinical presentation heel pain with maximal tenderness over the course of the inferior calcaneal nerve (on the plantar medial aspect of the foot and anterior to the ...

Bayonet deformity

Bayonet deformity is a term used to describe the shape of the wrist in certain conditions: Madelung deformity hereditary multiple exostosis with pseudo-Madelung deformity retarded bone growth of the distal ulna with outward bowing of the radius with distal radioulnar joint subluxation Colles...

Becker muscular dystrophy

Becker muscular dystrophy (BMD) is a dystrophinopathy that is considered to be a milder form of Duchenne muscular dystrophy. Epidemiology 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. Clinica...

Benign fibrous histiocytoma of bone

Benign fibrous histiocytoma is closely related to fibroxanthoma of bone, is a rare lesion usually occurring in the skin where it is known as dermatofibroma. Clinical presentation Typically presents with pain, and most often in the third decade. Pathology Only a few case reports have been pub...

Benign lytic bone lesions

Benign lytic bone lesions encompass a wide variety of entities. A useful starting point is the FEGNOMASHIC mnemonic. This article is a stub, which means it needs more content. You can contribute to Radiopaedia too. Just register and click edit... every little bit helps. See also malignant l...

Benign lytic bone lesions that rarely occur in patients over 30 (mnemonic)

A mnemonic to remember five benign lytic lesions that rarely occur in patients over 30 years of age. SCAN Everything Mnemonic S - simple bone cyst C - chondroblastoma A - aneurysmal bone cyst N - non-ossifying fibroma E - eosinophilic granuloma In a patient older than 30 years of age th...

Benign notochordal cell tumor

Benign notochordal cell tumors are vertebral lesions that are usually asymptomatic and discovered incidentally on imaging of the head or spine. As this is a poorly-recognised entity, it can often be confused with aggressive vertebral lesions, such as a chordoma, when it is seen on imaging. Epid...

Bennett fracture

A Bennett fracture is a fracture of the base of the thumb resulting from forced abduction of the first metacarpal. It is defined as an intra-articular two-part fracture of the base of the first metacarpal bone. Radiographic features Plain radiograph two piece fracture of the base of the thumb...

Bennett lesion of the shoulder

Bennett lesions of the shoulder, also called thrower's exostosis refers to the mineralisation of the posterior band of the inferior glenohumeral ligament. Epidemiology The abnormality is more prevalent in overhead throwing athletes. Associations It is associated with posterior labral tears,...

Bent bone dysplasias (differential)

Bent bone dysplasias are a class of dysplasia included in a 2010 classification of genetic skeletal disorders 1. campomelic dysplasia Stuve-Weidemann dysplasia kyphomelic dysplasias, a diverse class, including congenital bowing of the long bones cartilage-hair hypoplasia (CHH; metaphyseal d...

Berndt and Harty classification

Berndt and Harty classification is used for osteochondral lesions of the talus. Classification stage I: subchondral bone compression (marrow edema) stage II stage IIa: subchondral cyst stage IIb: incomplete separation of fragment stage III: complete separation but no displacement stage IV...

Bernese osteotomy

Bernese osteotomy, also known also Ganz osteotomy, is an orthopedic procedure involving osteotomy surrounding the acetabulum and subsequent angulation to improve coverage of the femoral head by the acetabulum. It is performed in the context of hip dysplasia. There is an osteotomy through the sup...

Bertolotti syndrome

Bertolotti syndrome refers to the association between lumbosacral transitional vertebrae (LSTV) and low back pain, and can be an important cause in young patients. It is considered controversial and has been both supported and disputed since Mario Bertolotti first described it in 1917. Some st...

Beta angle (developmental dysplasia of the hip)

The beta angle is a measurement used in the ultrasonographic assessment of developmental dysplasia of the hip (DDH). It is defined as the angle formed between the vertical cortex of the ilium and the triangular labral fibrocartilage (echogenic triangle) and thus reflects the femoral head cartil...

Biceps brachii

The biceps brachii muscle (also known simply as biceps) is a two-headed muscle in the anterior compartment of the arm that flexes at the elbow and supinates the forearm. Summary origin short head: coracoid process of the scapula long head: supraglenoid tubercle of the scapula insertion: rad...

Biceps brachii tendon rupture

Biceps brachii rupture can occur at either superior or inferior attachment but most commonly involves the long head at its proximal origin at the superior glenoid labrum. Rupture of the distal biceps rupture causes weakness when supinating the forearm. It is therefore associated with significant...

Biceps chondromalacia

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. Pathology The long head of biceps brachii arises from the supraglenoid tubercle of the glenoid fossa and has an intra- and extra-arti...

Biceps femoris muscle

The biceps femoris is one of the large muscles in the posterior compartment of the thigh and a component of the hamstrings. It has a long and a short head, each with different functions and innervation. Summary origin long head: medial facet of the ischial tuberosity short head: lateral line...

Biceps pulley

Biceps pulley refers to a complex capsuloligamentous structure which provides stability and hold the long head of biceps tendon within the bicipital groove. It comprises of the coracohumeral ligament, superior glenohumeral ligament, and distal attachment of the subscapularis tendon. Related pat...

Biceps pulley injury

Biceps pulley injuries can be challenging and difficult to diagnose. They can be missed during open and arthroscopic examination, and therefore have sometimes been referred to as a “hidden lesions”. Anatomy of Biceps Pulley: The biceps pulley or “sling” is a complex capsuloligamentous structur...

Bicipitoradial bursa

The bicipitoradial bursa is located between the distal biceps brachii tendon and the tuberosity of the radius. The bursa partially or completely wraps around the biceps tendon. It ensures frictionless motion between the biceps tendon and the proximal radius during pronation and supination of the...

Bicipitoradial bursitis

Bicipitoradial bursitis refers to inflammation of the bicipitoradial bursa. The bicipitoradial bursa surrounds the biceps tendon in supination. In pronation, the radial tuberosity rotates posteriorly, which compresses the bicipitoradial bursa between the biceps tendon and the radial cortex whi...

Bifid median nerve

The median nerve may divide into two nerve bundles in the distal forearm and appear as a bifid median nerve in the carpal tunnel. It has an incidence of ~3%. The median nerve usually divides into two or three branches after exiting the distal edge of the transverse carpal ligament that covers...

Bifid rib

Bifid or forked ribs are uncommon. They are thought to occur in ~0.2% of the population and there may be a female as well as right-sided predilection 2. Clinical presentation Usually asymptomatic, they may cause musculoskeletal pain or intercostal nerve entrapment. A bifid first rib is an unco...

Bifurcate ligament

The bifurcate ligament arises from the anterior process of the calcaneus as a single band and divides into calcaneocuboid (lateral) and calcaneonavicular (medial) parts forming a Y-shape.

Bilateral facet dislocation

A bilateral facet dislocation is an unstable flexion distraction type of dislocation of the cervical spine, often a result of buckling force. Occasionally, the bilateral facet dislocation has been named a 'doubly-locked' vertebral injury giving the impression of stability. However, due to comple...

Bilateral thinning of the parietal bones

Bilateral thinning of the parietal bones, also known as biparietal osteodystrophy, is an uncommon, slowly progressive acquired disease of middle-aged people with slight female predilection. It is typically an incidental finding. Pathology The etiology is unknown but is thought to be an age-re...

Bipartite medial cuneiform

A bipartite medial cuneiform is an anatomical variant where there are two ossification centers involving the medial cuneiform. In many cases the overall shape of the medial cuneiform is conserved, although the size of the two combined bones is larger than that of a normal medial cuneiform. Epid...

Bipartite patella

A bipartite patella (two-part patella) is a patella with an unfused accessory ossification center at the superolateral aspect. Epidemiology The superolateral accessory ossification center of the patella is usually present by 12 years of age and may persist into adult life. Prevalence of a bipa...

Bipartite scaphoid

A bipartite scaphoid is a rare example of a divided carpus. There is controversy whether this condition is congenital (i.e. normal variant) or post-traumatic. Bipartite scaphoids may be unilateral or bilateral. Diagnostic criteria have been proposed 3: no history of traumatic injury normal ap...

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