Articles
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4,267 results found
Article
≤11 ribs (differential)
≤11 ribs is associated with a number of congenital abnormalities and skeletal dysplasias, including:
Down syndrome (trisomy 21)
campomelic dysplasia
kyphomelic dysplasias
asphyxiating thoracic dysplasia (Jeune syndrome)
short rib polydactyly syndromes
trisomy 18
chromosome 1q21.1 deletion...
Article
12q14 microdeletion syndrome
12q14 microdeletion syndrome or osteopoikilosis-short stature-intellectual disability syndrome is caused by heterozygous deletion at the region of 12q14. The microdeletion affects the LEMD3 gene which has already been implicated in osteopoikilosis.
Epidemiology
Prevalence is <1 in 1 million li...
Article
18q deletion syndrome
18q deletion syndrome is a rare chromosomal anomaly where there is a deletion of part of the long arm of chromosome 18. Associated symptoms and findings vary widely, as do their severity. Characteristic clinical features include short stature, intellectual disability, hypotonia, facial, and dist...
Article
5th metacarpal pit
The 5th metacarpal pit refers to the normal exaggeration of the pit-like depression in the head of fifth metacarpal 1.
Differential diagnosis
It should not be mistaken for a boxer fracture (old or new) or an erosion.
Article
Abdominal hernia
Abdominal hernias/herniae may be congenital or acquired and come with varying eponyms. They are distinguished primarily based on type, location and content.
Epidemiology
75-80% of all hernias are inguinal ref.
Pathology
Content of the hernia is variable, and may include:
small bowel loops
...
Article
Abdominal surface anatomy
Abdominal surface anatomy can be described when viewed from in front of the abdomen in 2 ways:
divided into 9 regions by two vertical and two horizontal imaginary planes
divided into 4 quadrants by single vertical and horizontal imaginary planes
These regions and quadrants are of clinical imp...
Article
Abdominal wall injury
Abdominal wall injuries comprise a set of injuries of the abdominal wall and include different forms of muscle injuries, traumatic hernias and injuries to the subcutaneous tissue. They are often overshadowed by the attention to associated “more severe” abdominal visceral injuries.
Epidemiology...
Article
Abductor digiti minimi muscle (foot)
The abductor digiti minimi muscle is on the lateral side of the foot and contributes to the large lateral plantar eminence on the sole.
Summary
origin: lateral and medial processes of calcaneal tuberosity, and band of connective tissue connecting calcaneus with base of the fifth metatarsal
in...
Article
Abductor digiti minimi muscle (hand)
The abductor digiti minimi muscle overlies the opponens digiti minimi muscle, within the hypothenar eminence, and is one of the intrinsic muscles of the hand. Occasionally an accessory abductor digiti minimi muscle of the hand is present.
Summary
origin: pisiform, pisohamate ligament, and tend...
Article
Abductor hallucis muscle
The abductor hallucis muscle forms the medial margin of the foot and contributes to a soft tissue bulge on the medial side of the sole.
Summary
origin: medial process of calcaneal tuberosity
insertion: medial side of base of proximal phalanx of great toe
action: abducts and flexes great toe ...
Article
Abductor pollicis brevis muscle
The abductor pollicis brevis muscle is a thin subcutaneous muscle located laterally in the thenar eminence of the hand, and is one of the intrinsic muscles of the hand.
Summary
origin: mainly from the flexor retinaculum
few fibers originate from the tubercles of scaphoid and trapezium and ten...
Article
Abductor pollicis longus muscle
The abductor pollicis longus (APL) muscle is found in the deep layer of the posterior compartment of the forearm. As it descends, it becomes superficial and passes under the extensor retinaculum and through the 1st extensor compartment of the wrist before attaching distally. It is one of the ext...
Article
ABER position
The ABER position relates to MR arthrography of the shoulder joint and is a mnemonic for ABduction and External Rotation.
In this position, labral tears are made conspicuous by tightening the inferior glenohumeral labroligamentous complex (which are also the most important glenohumeral ligament...
Article
Abnormal ultrasound findings in rheumatological diseases (definitions)
The OMERACT ultrasound group published a consensus in 2005 of widely accepted definitions of abnormal ultrasound findings in rheumatological diseases:
erosion: an intra-articular discontinuity of the bone surface that is visible in two orthogonal planes 4
joint effusion: abnormal hypoechoic or...
Article
Abscess
Abscesses are focal confined collections of suppurative inflammatory material and can be thought of as having three components 1:
a central core consisting of necrotic inflammatory cells and local tissue
peripheral halo of viable neutrophils
surrounded by a 'capsule' with dilated blood vessel...
Article
Absent bow tie sign (knee)
The absent bow tie sign represents the loss of the normal appearance of the menisci on parasagittal MRI images and is suggestive of meniscal injury.
Normally the medial and lateral menisci appear as low signal triangular structures linked by a thin body located between the femoral condyles and ...
Article
Absent patella
An absent patella is a rare finding and can be found with an equally rare set of associations:
surgical removal of patella (patellectomy)
nail patella syndrome 2
popliteal pterygium syndrome
proximal focal femoral deficiency (PFFD)
Meier-Gorlin syndrome 3
Article
Absent thumb
An absent thumb can have many associations. They include:
Fanconi anemia (pancytopenia-dysmelia syndrome)
Franceschetti syndrome
Holt-Oram syndrome
phocomelia (e.g. thalidomide embryopathy)
Poland syndrome (pectoral muscle aplasia and syndactyly)
Rothmund-Thomson syndrome
Seckel syndrome ...
Article
Accessory abductor digiti minimi muscle (hand)
An accessory abductor digiti minimi (ADM) muscle is the most common accessory muscle of the hand and wrist, found in 24% of individuals on the hypothenar eminence. When present it is one of the intrinsic muscles of the hand.
Summary
origin:
antebrachial fascia passing anteriorly to Guyon cana...
Article
Accessory anterior inferior tibiofibular ligament
The accessory anterior inferior tibiofibular ligament (accessory AITFL), also known as Bassett's ligament, is an anatomical variant present in many ankles. Pathological thickening of the accessory ligament is seen in the setting of inversion injury that causing the pain due to mild anterior inst...
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