Articles
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52 results found
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
Lead pipe fracture
The term lead pipe fracture is the term for a radiographic appearance given to a simultaneous greenstick fracture of one side of the bone (usually metaphysis) with a buckle fracture of the opposing cortex of the same bone.
There are differing opinions in texts as to whether this term should be...
Article
Tadpole sign
The tadpole sign, also known as the lollipop sign, refers to a characteristic morphology of post-traumatic bridging vein thrombosis with a rounded "head" and a tapering "tail". The finding demonstrates a high specificity for abusive head trauma, a sub-type of non-accidental injury, and should wa...
Article
Aubergine sign (penis)
The aubergine sign (also known as egg-plant sign or deformity) is a clinical sign of a fractured penis. Hemorrhage beyond the tunica albuginea produces swelling and bruising of the penis simulating the appearance of an aubergine.
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
V sign of interphalangeal joint dislocation
The V sign is characterized on a lateral radiograph of the digit by the separation of the dorsal base of the dislocated phalanx and the head of the phalanx proximal to the incongruent joint 1,2.
Before reduction, the V sign might be assessed to identify more subtle dorsal subluxations 1.
If th...
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
Raccoon eyes sign (base of skull fracture)
Raccoon eyes sign (or panda eyes in the UK and Ireland) refers to periorbital ecchymosis with sparing of the tarsal plate 3 and is a physical examination finding indicative of a base of skull fracture of the anterior cranial fossa.
However it is not pathognomonic for trauma, and there are sever...
Article
Deep sulcus sign (disambiguation)
The deep sulcus sign can refer to two different radiographic signs but is best known in the chest:
deep sulcus sign (chest): of pneumothorax on supine CXR:
deep sulcus sign (knee): better known as the lateral femoral notch sign of ACL injury
Article
CT comma sign (head)
The CT comma sign is a characteristic sign seen in head trauma. It is the presence of concurrent epidural and subdural hematomas, which gives the characteristic appearance of this sign as a "comma" shape.
Article
Yo-yo on a string sign - Stener lesion
The yo-yo on a string sign denotes the characteristic appearance of the torn, proximally retracted and superficially displaced ulnar collateral ligament (UCL) due to a Stener lesion.
Mechanism
The sign occurs as a consequence of the tear of the ulnar collateral ligament of the thumb (gamekeepe...
Article
Seurat spleen
Seurat spleen is an angiographic appearance seen following blunt trauma to the spleen. Multiple small punctate regions of intraparenchymal contrast extravasation lead to a spotted appearance.
Pathology
Several mechanisms are thought to to attribute to this appearance which include sinusoidal s...
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...
Article
Pericardial fat tag sign (pneumothorax)
The pericardial fat tag sign is a sign of pneumothorax on supine CXR where the cardiac border has a lumpy contour.
When gas is located in the pleural space between the lung and mediastinum, the pericardial fat is no longer compressed against the mediastinum and therefore can hang or dangle late...
Article
Light bulb sign (posterior shoulder dislocation)
The light bulb sign refers to the abnormal AP radiograph appearance of the humeral head in posterior shoulder dislocation.
When the humerus dislocates it also internally rotates such that the head contour projects like a light bulb when viewed from the front 1.
See also
light bulb sign (hepat...
Article
Costal hook sign (flail chest)
The costal hook sign is a chest x-ray feature seen in some cases of flail chest. It represents the rotation of a fractured rib along its long axis, something that is only possible if a second fracture is present along its length, even if the second fracture is not visible 1.
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
O'Donoghue unhappy triad
O'Donoghue unhappy triad or terrible triad often occurs in contact and non-contact sports, such as basketball, football, or rugby, when there is a lateral force applied to the knee while the foot is fixated on the ground. This produces an abduction-external rotation mechanism of injury ("pivot s...
Article
Burst lobe
A burst lobe is an uncommonly used description of traumatic lobar intraparenchymal hemorrhage of the brain that ruptures into the subdural space and communicates with subdural hemorrhage 1.
As traumatic hemorrhages are more common in the frontal and temporal lobes, these lobes are the most affe...
Article
Extracranial brain herniation
Extracranial or transcalvarial brain herniation refers to herniation of brain tissue external to the calvaria through a skull bone defect, which may be post-traumatic or post-surgical. Unlike encephaloceles, brain herniation is not surrounded by the meninges.
Craniectomy may be performed to de...
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