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
joint effusion: abnormal hypoechoic or a...
Achondrogenesis type Ib, also known as Parenti-Fraccaro subtype, is a subtype of achondrogenesis and is an extremely rare skeletal dysplasia (chondrodysplasia).
Undersulphation has a pronounced effect on the composition of the extracellular matrix of cartilage, and this has been sh...
Acromiohumeral interval is a useful and reliable measurement on AP shoulder radiographs and when narrowed is indicative of rotator cuff tear or tendinopathy.
Measurements of the acromiohumeral interval in the following intervals are suggestive of pathology 1-2:
>12 mm: shoulder dis...
The Amsterdam wrist rules are validated clinical decision rules for determining which patients require radiographic imaging (wrist radiography) for acute wrist pain following trauma. The initial study evaluated 882 patients and were published in 2015 1. The decision rules assessed different clin...
Ankle AP view is part of a three view series of the distal tibia, distal fibula, proximal talus and proximal metatarsals.
the patient may be supine or sitting upright with their leg straighten on the table
the foot is in dorsiflexion
the toes will be pointing directly toward...
Blumensaat line is the line drawn along the roof of the intercondylar notch of the femur as seen on lateral radiograph of the knee joint. It can been used for:
indicating the relative position of the patella as normally this line intersects the lower pole of the patella
suggesting ACL injury a...
Böhler angle, also written as Bohler angle or Boehler angle, is also called the calcaneal angle or tuber joint angle 1, and is the angle between two lines tangent to the calcaneus on the lateral radiograph. These lines are drawn tangent to the anterior and posterior aspects of the superior calca...
Canadian C-spine rules are a set of guidelines that help a clinician decide if cervical spine imaging is not appropriate for a trauma patient in the emergency department. The patient must be alert and stable.
There are three rules:
is there any high-risk factor present that requires cervical s...
The cases featured in these video lectures are specifically selected to teach important concepts in radiology over a broad range of topics. The tutorials vary in difficulty from basic to advanced. For maximum learning, try the cases for yourself in Radiopaedia quiz mode first.
We love this ser...
Chest x-ray review is a key competency for medical students, junior doctors and other allied health professionals. Using A, B, C, D, E is a helpful and systematic method for chest x-ray review where D refers to disability and specifically fractures and dislocations.
This is a...
The coracoclavicular (CC) distance is an indicator of the integrity of the coracoclavicular (CC) ligament.
The CC distance is assessed on a frontal radiography of the shoulder or clavicle or the coronal projection or a CT or MRI as the distance between the superior cortex...
Coxa magna is the asymmetrical, circumferential enlargement and deformation of the femoral head and neck. Definitions in the literature vary but enlargement with asymmetry >10% in size is a reasonable cut-off for diagnosis 1.
Coxa profunda refers to a deep acetabular socket. On pelvis x-rays it is seen as the acetabular fossa being medial to the ilioischial line. It should be differentiated from protrusio acetabuli, where the femoral head is seen additionally medial to the ilioischial line. Coxa profunda is much more...
Describing a fracture is a basic requirement when making an assessment of a plain radiograph. There are many ways to approach the assessment of the radiograph; this is just one approach.
I: Describe the film
What film (or films) are you looking at? Check the who, what, why, when, and where.
Elbow radiographs are common plain films that are obtained frequently in the emergency department.
anterior humeral line
drawn down the anterior surface of the humerus
should intersect the middle 1/3 of the capitellum
if it does not, think distal humeral fracture...
Distinguishing between enchondromas and low-grade conventional chondrosarcomas is a frequent difficulty as the lesions are both histologically and radiographically very similar.
It is important to remember, though, that differentiating between them may be a moot point since both can either be c...
Recurrent bone tumours are a common complication post curettage or resection.
Radiographs taken pre- and postoperatively are sufficient for evaluation of recurrence based on the following features:
matrix mineralisation (characterist...
The first metatarsal axis is represented by a line drawn down the longitudinal axis of the shaft of the first metatarsal. It can be drawn on lateral and DP radiographs and is used to measure the:
first metatarsal inclination angle
talo-first metatarsal angle
The lateral projection is part of the three view series examining the phalanges, metatarsals and tarsal bones that make up the foot.
The lateral projection additionally examines the talocrural joint.
the patient may be supine or upright depending on comfort
the affected le...
Foot radiographs are commonly performed in Emergency departments, usually after sport-related trauma and often with a clinical request that states lateral border pain. Remember to check the whole film, though. Often, a foot x-ray is also requested for the investigation of osteomyelitis, arthriti...
Gissane angle, also known as the "critical angle", is an angular measurement made directly inferior to the lateral process of the talus. It is formed by the downward and upward slopes of the calcaneal superior surface. It is better seen on a lateral plain film of the calcaneus and hindfoot. Its ...
Hindfoot equinus describes abnormal plantarflexion (calcaneotibial angle >90°) of the foot that occurs in the hindfoot. It occurs in congenital talipes equinovarus and congenital vertical talus.
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, ...
The intermetatarsal (IM) angle refers to the angle measured between the 1st and 2nd metatarsal shaft on an axial view of the foot. In normal situations it is considered to be under 9°. The angle can increase with hallux valgus and metatarsus adductus deformities.
This article is dedicated to the humble joint effusion, particularly the plain radiographic appearances.
A joint effusion is defined as an increased amount of fluid within the synovial compartment of a joint. There is normally only a small physiological amount of fluid. Abnormal fluid accumulat...
Low grade osteosarcoma is an uncommon subtype of osteosarcoma accounting less than 1% of all osteosarcomas.
Low grade osteosarcoma affects individuals of higher age group as compare to the other subtypes of osteosarcoma. The usual age of presentation is 19 to 54 years with the mea...
Magnetic resonance neurography (MRN) is a relatively new non-invasive imaging technique for dedicated assessment of peripheral spinal nerves.
It is used to assess peripheral nerve entrapments and impingements as well as localization and grading of nerve injuries and lesions.
The McGregor line is a modification of the Chamberlain line and is used in the evaluation of basilar invagination when the opisthion is not identified on plain radiographs.
It refers to a line connecting posterior edge of the hard palate to the most caudal point of the occipital curve. If the t...
Midfoot equinus is an abnormality in foot alignment where there is abnormal plantarflexion of the foot in the midfoot.
Midfoot equinus occurs as a component of congenital talipes equinovarus.
Monoarticular arthropathy can result from a number of causes:
HADD (hydroxyapatite deposition disease)
MRI of the brachial plexus is used to provide a causal diagnosis for brachial plexopathies. It provides clear structural analysis of the brachial plexus, its intraneural integrity, as well as surrounding structures 1,3.
brachial plexus injuries
grading of brachial plexus inj...
NEXUS (National Emergency X-Radiography Utilization Study) is a set of validated criteria used to decide which trauma patients do not require cervical spine imaging.
Trauma patients who do not require cervical spine imaging:
alert and stable
no focal neurologic deficit
no altered level of co...
Normal radiographic measurements of the shoulder are important in evaluation of the osseous relationships in plain film radiography. Normal measurements do not rule out pathology, and must be considered in the context of other findings and the clinical presentation.
AC joint space: 2-4 mm
Differential diagnosis of lytic bone lesions with septations and trabeculations include 1:
unicameral bone cyst
aneurysmal bone cyst
giant cell tumour
The Ottawa ankle rules are a clinical decision-making strategy for determining which patients require radiographic imaging for ankle and foot injuries. Proper application has high (97.5%) sensitivity and reduces the need for radiographs by ~35% 1,2,4.
There are two components, assessing for an...
The Ottawa knee rules are a clinical decision-making strategy for determining which patients require radiographic imaging for knee pain.
A patient with knee pain qualifies for a radiograph if:
55 years or older
point tenderness at the fibular head
isolated point tenderness of the patella
Paediatric elbow radiographs are commonly encountered in the emergency department and, when approached in a systematic fashion, are not as difficult to interpret as most people think!
Check that the ossification centres are present and in the correct position. T...
Radiographic evaluation of anterior cruciate ligament (ACL) reconstruction involves:
a line is drawn along the posterior cortex of the femur
a second line is drawn along the roof of the intercondylar notch of the femur (Blumensaat line)
the point of intersection of these tw...
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 ...
The scapholunate interval is the radiographic measurement of the scapholunate joint on PA wrist projections. Abnormal widening is indicative of injury to the scapholunate ligament that occurs with scapholunate dissociation.
In adults, the normal value is usually taken as <2 mm, with an interva...
Shortened fetal humerus is a morphological description and is usually defined when the humeral length falls below the 5th percentile or less than 0.9 predicted by the bipareital diameter (BPD). It can occur in isolation or in association with a number of other anomalies.
The humeral length is n...
Shoulder radiographs are common films to see in the Emergency Department, especially during the weekend after sporting events.
articular surfaces should be parallel
the humeral head should be on the glenoid in any other view
if the humeral head lies unde...
Shoulder radiographs are commonly performed for shoulder injury assessment and followup. Using a standard system to approach the x-ray means it is much more likely you will find the abnormality.
glenohumeral joint - shoulder dislocation
the humeral head is adjacent...
A skeletal survey is a series of radiographs, performed systematically to cover the entire skeleton or the anatomic regions appropriate for the clinical indications.
A typical skeletal survey includes bilateral anteroposterior (AP) and posteroanterior (PA) projections of hands, forearms, humeru...
Cricket is a popular game in Commonwealth countries, injuries in this game can be associated with three aspects of the game: bowling, batting or fielding. Radiologists should know the different kind of injuries related to this game for a better clinical association. Injuries can range from a mus...
Subcutaneous calcification can be associated with a number of disorders. The list includes:
basal cell nevus syndrome
as a manifestation of systemic lupus erythematosus
Trabecular pattern of proximal femur refers to the five groups of trabeculae that are demonstrable within the femoral head and neck.
Trabecula is a supportive and connective tissue element which form in cancellous bone. Trabeculae develop in a normal bone and also in a healing bo...
Musculoskeletal tuberculosis is always secondary to a primary lesion in the lung.
The prevalence of the disease is around 30 million globally and 1-3% of the 30 million have involvement of their bones and/or joints. Mycobacterium tuberculosis is responsible for almost all of the c...
Tuberculous arthropathy is a type of musculoskeletal manifestation of tuberculosis (TB) and a common cause of infectious arthritis in developing countries. Any pathological joint lesion where the exact diagnosis is equivocal should be considered tubercular in origin unless proven otherwise.
Tumours that metastasise to bone may be remembered using the mnemonic "lead kettle" spelled PBKTL (lead is Pb on the Periodic Table).
For females, breast and lung are the most common primary sites; nearly 80% of cancers t...
Ultrasound of the elbow allows high-resolution imaging of elbow anatomy while simultaneously allowing dynamic evaluation of the joint, tendons, and ligaments.
There are multiple possible approaches to imaging the elbow with ultrasound. A typical protocol is as follows 1:
Ultrasound of the knee allows high-resolution imaging of superficial knee anatomy while simultaneously allowing dynamic evaluation of some of the tendons and ligaments. Knee ultrasound is somewhat limited compared with ultrasound examinations of other joints because the cruciate ligaments and th...
Ultrasound is a useful imaging modality for evaluation of the wrist, allowing high-resolution imaging of anatomy while simultaneously allowing dynamic evaluation of the joint, tendons, and ligaments.
There are multiple possible approaches to imaging the wrist with ultrasound. The exam...
Reporting a weightbearing foot series can be a daunting process if you are inexperienced and often results in the films being left for somebody else to report. This article attempts to demystify the whole process by providing a structured approach to their reporting.
Wrist radiographs are ubiquitous on any night of the week in emergency departments, especially when pavements are icy!
Distal radial contour
Check the contour of the distal radius:
the distal radial articular surface should cup the carpals
the articular surface should ...
Wrist x-rays are commonly used for the assessment of the wrist following trauma. This is usually a fall onto an outstretched hand.
It is useful to have a systematic approach; I tend to start proximally and work distally looking at structures on both views together:
Wrist radiographs are commonly used for the assessment of the wrist following trauma.
distal radius and ulna have smooth joint surface
carpal arcs are smooth
carpal bones do not overlap
apart from pisiform and trapezium
metacarpals do not overlap and distal...