Articles
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52 results found
Article
Lipohemarthrosis
Lipohemarthrosis results from an intra-articular fracture with escape of fat and blood from the bone marrow into the joint, and is most frequently seen in the knee, associated with a tibial plateau fracture or distal femoral fracture; rarely a patellar fracture. They have also been described in ...
Article
Segond fracture
Segond fracture is an avulsion fracture of the knee that involves the lateral aspect of the tibial plateau and is very frequently (~75% of cases) associated with disruption of the anterior cruciate ligament (ACL). On the frontal knee radiograph, it may be referred to as the lateral capsular sign...
Article
Straight left heart border sign
Straight left heart border sign is a described finding on chest radiograph in cases of hemopericardium. It is a fairly specific (84%) sign of hemopericardium after a penetrating chest trauma, although sensitivity at 40% is relatively poor. Positive predictive value (PPV) was found to be 89% 1.
...
Article
Popeye sign
Popeye sign is a pronounced bulging muscle in the distal aspect of the biceps region of the arm. It is clinically apparent with a complete long head of biceps tendon tear which causes distal migration of the long head of biceps muscle.
History and etymology
Defined by the distal migration of...
Article
Pronator quadratus sign
The pronator quadratus sign, also known as MacEwan sign, can be an indirect sign of distal forearm trauma. It relies on displacement of the fat pad that lies superficial to the pronator quadratus muscle as seen on a lateral wrist radiograph.
Pathology
Displacement, anterior bowing, or oblitera...
Article
Pellegrini-Stieda lesion
Pellegrini-Stieda lesions refer to ossified post-traumatic lesions at (or near) the medial femoral collateral ligament adjacent to the margin of the medial femoral condyle. One presumed mechanism of injury is a Stieda fracture (avulsion injury of the medial collateral ligament at the medial femo...
Article
V sign (disambiguation)
Signs inspired by the letter V have been described in several different pathologies:
inverted V sign (pneumoperitoneum)
inverted V sign (spinal cord)
Naclerio V sign (pneumomediastinum)
V sign (interphalangeal joint subluxation)
V sign (midbrain)
Article
Anomalous insertion of the medial meniscus
Anomalous insertion of the medial meniscus (AIMM) is an anatomical variation of the insertion of the anterior root of the medial meniscus.
Terminology
Defined as a congenital variation in the insertion of the anterior root of the medial meniscus onto the anterior cruciate ligament (ACL). The...
Article
Flat tyre sign (globe rupture)
The flat tyre sign, also known as the mushroom sign, is one of the most specific signs of ruptured eye globe, due to the similarity between the abnormal contour of injured globe and the appearance of a flat tyre 1. It is classically described on CT but may be seen on ultrasound or MRI 2.
The mo...
Article
Starfield pattern (fat embolism)
A starfield pattern has been described as being typical of DWI of patients with cerebral fat embolism 1,2. Although the term is closely linked to the diagnosis of fat embolism, it should be noted that such an appearance is merely the result of very numerous microemboli. As such, a similar patter...
Article
Sail sign (elbow)
The sail sign on an elbow radiograph, also known as the anterior fat pad sign, describes the elevation of the anterior fat pad to create a silhouette similar to a billowing spinnaker sail from a boat. It indicates the presence of an elbow joint effusion.
The anterior fat pad is usually conceale...
Article
Deep sulcus sign (chest)
The deep sulcus sign on a supine chest radiograph raises suspicion of a pneumothorax.
On a supine chest radiograph (common in intensive care units or as part of a trauma radiograph series), it may be the only suggestion of a pneumothorax because air collects anteriorly and basally, within the n...
Article
Double delta sign (meniscal tear)
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...
Article
Pooping duck sign
Pooping duck sign indicates the presence of a triquetral fracture on a lateral wrist radiograph, where an avulsed fracture fragment from the dorsal cortex of the triquetrum projects along the dorsal aspect of the osseous structures of the wrist.
In this sign, the fracture fragment represents th...
Article
Posterior fat pad sign (elbow)
The posterior fat pad sign is the visualization of a lucent crescent of fat located in the olecranon fossa on a true lateral view of an elbow joint with the elbow flexed at a right angle indicating an elbow joint effusion1. Normally, the posterior fat pad will not be seen in this view 2.
In th...
Article
Bow tie sign
The bow tie sign refers to the appearance of rotated facets in unilateral facet joint dislocation. Facet joint displacement coupled with a rotational deformity gives a bow-tie like appearance on a lateral view radiograph of spine 1.
Article
Broken heart sign
The broken heart sign, also known as the Y sign in older otorhinolaryngology literature 2,3, describes the appearances of incudomalleolar disarticulation.
This sign is identified on CT in the coronal plane, being formed by the widening of the incudomalleolar joint and lateral displacement of th...
Article
Orbital emphysema
Orbital emphysema is the presence of gas within the orbital soft tissues. It is usually due to orbital fractures communicating with the paranasal sinuses but can be caused by penetrating trauma and infection. It is a common finding also after orbital or ocular surgery.
Location
preseptal
pos...
Article
Double-arc sign
The double-arc sign, also known as the McKee double-arc sign, is a radiographic indication of a coronal shear fracture of the distal humerus, which involves the capitellum and extends beyond the lateral trochlear ridge to include a part of the trochlea 1,2.
The double-arc sign is characterized ...
Article
Psoas sign (abdominal x-ray)
The psoas sign is a classic albeit non-specific finding on the abdominal radiograph, potentially representing retroperitoneal pathology.
Normally on an abdominal radiograph, the lateral margins of both the psoas muscles are clearly visible due to adjacent fat. When the lateral edge of one, or b...