Articles

Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.

138 results found
Article

Liposuction

Liposuction is a cosmetic procedure to reduce the volume of adipose tissue in the neck, arms, legs and/or abdomen. Areolar fat, a deeper layer of adipose tissue, is the main target and shows a good response to vacuum-assisted liposuction.  There are three types of this procedure 1,2: power-ass...
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Subperiosteal abscess

Subperiosteal abscesses refer to the subperiosteal spread of infection characterized by purulent encapsulated fluid collections within the subperiosteal space. Epidemiology Subperiosteal abscesses are more often seen in children than in adults 1,2. Associations Subperiosteal abscesses have b...
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Ulcer (soft tissue)

An ulcer refers to the break in the skin, epithelium, or mucous membrane resulting in the discontinuity in the surface tissue, necrosis, and often pus formation 1. Risk factors immunocompromised (e.g. diabetics) 1 immobile patients 1,2 advanced age 2 poor nutrition 2 increased moisture 2 ...
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Sinus tract

Sinus tracts are an abnormal connection between a fluid collection with a mucous mucosal surface and/or skin 1,2. It can result from acute or chronic processes and occasionally extend into the joints and bones 1. Terminology The term sinus tract is non-specific; however, when used in soft tiss...
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Talocrural angle

The talocrural angle can be used to assess for fibular shortening after a fracture. Measurement The talocrural angle is measured on the mortise view as the angle between a line along the distal tibial plafond articular surface and another line joining the tips of both malleoli 3,4.  Interpret...
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First metatarsal declination angle

The first metatarsal declination angle can be used to assess for metatarsus primus elevatus in hallux rigidus.  Measurement The first metatarsal declination angle is formed between the longitudinal axis of the first metatarsal and the supporting surface 1-4.  Interpretation normal: 20-21° 1-...
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Patellofemoral angle

The patellofemoral angle is a measure of patellar tilt and is useful in the diagnosis of patellofemoral instability and excessive lateral pressure syndrome.  Measurement The patellofemoral angle is formed between a line drawn along the bony lateral patellar facet and another line drawn along t...
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Fourth-fifth intermetatarsal angle

The fourth-fifth intermetatarsal angle is used to assess for a bunionette deformity. It should not be confused with the first intermetatarsal angle, used to assess for hallux valgus deformity.  Measurement The fourth-fifth intermetatarsal angle is formed between the long axis of the fourth and...
Article

Friedman line

The Friedman or scapular line can be used to determine glenoid version and glenoid bone loss 4. Glenoid version angle measured by the Friedman method has better inter-reader reliability than the scapular body method 2.  Measurement The Friedman line is drawn along the long axis of the scapula ...
Article

AP Meary's angle

AP Meary's angle or AP talus-first metatarsal angle is used to assess for midfoot abduction/adduction in pes planus and pes cavus to assist with pre-operative planning 1.  Measurement On a weight-bearing AP foot radiograph, a line is drawn down the longitudinal axis of the first metatarsal to ...
Article

Posterior tibial line

The posterior tibial line is drawn along the posterior aspect of the distal tibial shaft on a lateral ankle x-ray and can be used to assess the sagittal alignment of the talus when comparing side-to-side and/or calculate the posterior tibial line-talar ratio 1,2.
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Medial cuneiform to second metatarsal distance

Medial cuneiform to second metatarsal distance is the measurement of the distance between the lateral aspect of the medial cuneiform and the medial aspect of the base of the second metatarsal bone 1,2. Usage Medial cuneiform to second metatarsal distance is an important measurement used in ass...
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Lateral tibiotalar distance

Lateral tibiotalar distance is a measurement on an ankle anterior drawer lateral view to assess for ankle instability.  Measurement On an ankle anterior drawer lateral view (typically performed using a Telos device 2-4), the distance between the posterior tip of the distal tibial articular sur...
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Medial cuneiform-fifth metatarsal height

Medial cuneiform-fifth metatarsal height is the distance between the most inferior part of the medial cuneiform and the most inferior part of the base of the 5th metatarsal and is used to evaluate the height and integrity of the medial vertical arch 1. Usage Medial cuneiform-fifth metatarsal h...
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Quadratus femoris injection (technique)

Quadratus femoris injections under image guidance ensure precise delivery of an injectate and ensure the sciatic nerve is avoided during the procedure.  CT and ultrasound can be used, with ultrasound becoming more challenging in those with larger body habitus. Indications therapeutic for ischi...
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CT ankle (protocol)

The CT ankle protocol serves as an examination for the bony assessment of the ankle and rearfoot and is almost always performed as a non-contrast study. It can be also combined with a CT arthrogram for the evaluation of chondral and osteochondral injuries or can encompass the whole foot in certa...
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Gamma nail

The gamma nail or trochanteric nail is an osteosynthetic implant designed to treat proximal femoral fractures in the trochanter area with a closed intramedullary fixation method. The gamma nail consists of a funnel-shaped intramedullary nail with slight bending to reflect proximal femoral diaph...
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Pudendal nerve block (technique)

Pudendal nerve blocks are performed on those with suspected or proven pudendal neuralgia. Using CT will ensure accurate needle placement, which aims for a perineural pudendal nerve injection in the pudendal canal, also known as Alcock's canal.  Indications pudendal neuralgia diagnostic Contr...
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Extra-articular injection

Extra-articular injections occur when the needle tip is not within the targeted joint during joint injections. Terminology Defined by the presence of contrast outside of a joint in fluoroscopic or CT guided procedures, or the lack of direct visualization and resisted flow of intra-articular in...
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Knee joint injection (technique)

Knee joint injections under image guidance ensure precise delivery of an injectate into the knee joint. Either fluoroscopy, ultrasound or CT can be used to guide and administer injectates, which may be diagnostic (e.g. anesthetic), "therapeutic" (e.g. anesthetic/steroids, PRP), or for CT or MR a...
Article

Tibial torsion

Tibial torsion refers to the rotation or twist along the longitudinal axis of the lower leg or more specifically the tibial bone. Usage Internal tibial torsion is a cause of in-toeing gait a common rotational variant in toddlers, usually resolving spontaneously by the age of 5 years 1. Externa...
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Groin pain

Groin pain is a symptom manifesting in a wide spectrum of clinical disorders and diseases in athletes and non-athletes. The Doha agreement in 2014 identified and classified groin pain in athletes and defined the following clinical entities 1,2: adductor-related, pubic-related, inguinal-related...
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MRI of the wrist (an approach)

MRI of the wrist is a fairly frequent examination in musculoskeletal radiology practice and not quite as common in general radiological practice. This approach is an example of how to create a radiological report of an MRI of the wrist knee with coverage of the most common anatomical sites of po...
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MRI of the ankle (an approach)

MRI of the ankle is one of the more frequent examinations faced in daily radiological practice. This approach is an example of how to create a radiological report of an MRI of the ankle with coverage of the most common anatomical sites of possible pathology, within the ankle without claim for co...
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MRI of the elbow (an approach)

MRI of the elbow is a fairly frequent examination in musculoskeletal radiology practice and not quite as common in general radiological practice. This approach is an example of how to create a radiological report of an elbow MRI with coverage of the most common anatomical sites of possible patho...
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MRI of the shoulder (an approach)

MRI of the shoulder is one of the more frequent examinations faced in daily radiological practice. This approach is an example of how to create a radiological report of an MRI shoulder with coverage of the most common anatomical sites of possible pathology, within the shoulder. Systematic revie...
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MRI of the knee (an approach)

Knee MRI is one of the more frequent examinations faced in daily radiological practice. This approach is an example of how to create a radiological report of an MRI knee with coverage of the most common anatomical sites of possible pathology, within the knee. Systematic review A systematic rev...
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Elbow radiograph (checklist)

The elbow radiograph checklist is just one of the many pathology checklists that can be used when reporting to ensure that you always actively exclude pathology that is commonly missed; this is particularly helpful in the examination setting, e.g. the FRCR 2B rapid-reporting. Radiograph Elbow ...
Article

Tanner-Whitehouse method

The Tanner-Whitehouse (TW) method is a way of assessing the bone age of children. There are several variations of this method, but all use a DP radiograph of the left hand and wrist to assess the relative maturity of the bones of the patient. The TW2 (Tanner-Whitehouse 2) methods 1: RUS (radiu...
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Medial condyle trochlear offset

Medial condyle trochlear offset (MCTO) is a measurement to assess the height of the medial trochlear facet with respect to the trochlear groove 1. Usage Medial condyle trochlear offset has been described for the assessment of trochlear dysplasia in skeletally immature patients 1. It measures a...
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Ventral trochlear prominence

Ventral trochlear prominence (VTP) describes and measures the bony surplus in the anterior femoral surface at the most superior or proximal aspect of the trochlea. Usage Ventral trochlear prominence is used for the assessment of trochlear dysplasia, a risk factor for patellofemoral instability...
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Trochlear facet asymmetry

Trochlear facet asymmetry (FA) refers to the condition of the medial facet being abnormally small if compared to the lateral facet in trochlear dysplasia 1. Usage Facet asymmetry is also used as a measurement in magnet resonance imaging for trochlear dysplasia to make it more objective 1-3, th...
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Trochlear depth

Trochlear depth (TD) measures the depth of the trochlear groove in relation to the femoral condyles. Usage Trochlear depth is used for the assessment of trochlear dysplasia, a dysplastic deformity of the femoral head, which is a known risk factor for patellofemoral instability 1-6. A review o...
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Lateral trochlear inclination

Lateral trochlear inclination (LTI) is the inclination angle between the femoral trochlea and a posterior condylar tangential line 1. Usage The lateral trochlear inclination angle is used in the assessment of trochlear dysplasia, a dysplastic deformity of the distal femur, which is a known ris...
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Wrist radiograph (checklist)

The wrist radiograph checklist is just one of the many pathology checklists that can be used when reporting to ensure that you always actively exclude pathology that is commonly missed; this is particularly helpful in the examination setting, e.g. the FRCR 2B rapid-reporting. Radiograph Wrist ...
Article

Hand radiograph (checklist)

The hand radiograph checklist is just one of the many pathology checklists that can be used when reporting to ensure that you always actively exclude pathology that is commonly missed; this is particularly helpful in the examination setting, e.g. the FRCR 2B rapid-reporting. Radiograph Hand ra...
Article

Lumbar spine radiograph (checklist)

The lumbar spine checklist is just one of the many pathology checklists that can be used when reporting to ensure that you always actively exclude pathology that is commonly missed; this is particularly helpful in the examination setting, e.g. the FRCR 2B rapid-reporting. Radiograph The lumbar...
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Thoracic spine radiograph (checklist)

The thoracic spine checklist is just one of the many pathology checklists that can be used when reporting to ensure that you always actively exclude pathology that is commonly missed; this is particularly helpful in the examination setting, e.g. the FRCR 2B rapid-reporting. Radiograph These ra...
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Cervical spine radiograph (checklist)

The cervical spine checklist is just one of the many pathology checklists that can be used when reporting to ensure that you always actively exclude pathology that is commonly missed; this is particularly helpful in the examination setting, e.g. the FRCR 2B rapid-reporting. Radiograph Although...
Article

Medial clear space (ankle)

The medial clear space is a radiographic measurement that may be useful in the diagnosis of ankle instability, syndesmotic injuries and ankle fractures 5. Usage The medial clear space is used in the prediction of deltoid ligament injury 1 and in conjunction with the tibiofibular clear space th...
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Tibiofibular overlap

The tibiofibular overlap (TFO) is the overlapping area between the anterior distal tibial prominence and the medial edge of the distal fibula 1-3. Usage Together with the tibiofibular clear space (TFCS) and the medial clear space, the tibiofibular overlap space has been used in the diagnosis a...
Article

Tibiofibular clear space

The tibiofibular clear space is a radiographic measure and defined as the space between the groove of the distal tibial prominence and the medial margin of the distal fibula 1-3. Usage Together with the tibiofibular overlap and the medial clear space, the tibiofibular clear space has been used...
Article

Shoulder radiograph (checklist)

The shoulder radiograph checklist is just one of the many pathology checklists that can be used when reporting to ensure that you always actively exclude pathology that is commonly missed; this is particularly helpful in the examination setting, e.g. the FRCR 2B rapid-reporting. Radiograph Sho...
Article

First metatarsophalangeal angle

The first metatarsophalangeal angle, also known as hallux valgus angle (HVA) or hallux abductus angle, is a measurement used to assess the presence and severity of the alignment of the first metatarsophalangeal joint on a weight-bearing dorsoplantar radiograph of the foot. Measurement The angl...
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Foot radiograph (checklist)

The foot radiograph checklist is just one of the many pathology checklists that can be used when reporting to ensure that you always actively exclude pathology that is commonly missed; this is particularly helpful in the examination setting, e.g. the FRCR 2B rapid-reporting. Radiograph Foot ra...
Article

Pelvic radiograph (checklist)

The pelvic radiograph checklist is just one of the many pathology checklists that can be used when reporting to ensure that you always actively exclude pathology that is commonly missed; this is particularly helpful in the examination setting, e.g. the FRCR 2B rapid-reporting. Plain radiograph ...
Article

Knee radiograph (checklist)

The knee radiograph checklist is just one of the many pathology checklists that can be used when reporting to ensure that you always actively exclude pathology that is commonly missed; this is particularly helpful in the examination setting, e.g. the FRCR 2B rapid-reporting. Radiograph Knee ra...
Article

Sulcus angle (knee)

The sulcus angle is useful in the assessment of patellofemoral instability and trochlear dysplasia.  Measurement The angle is formed by the trochlear opening of the knee, measuring the angle between the medial and lateral facets. Classically described in axial x-rays of the knee performed at 3...
Article

Sternoclavicular joint injection (technique)

Sternoclavicular joint (SCJ) injections under image guidance ensure precise delivery of an injectate into the joint and importantly that needle depth is under direct visualization.   Indications pain arthropathy, e.g. osteoarthritis diagnostic injection Contraindications Absolute anaphyla...
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Elbow injection (disambiguation)

Elbow injection usually refers to an elbow joint injection, but especially to patients, it can be a term used referring to other procedures which include: common extensor origin microtenotomy common flexor origin microtenotomy distal biceps tendon sheath injection elbow joint injection MRI ...
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Foot injection (disambiguation)

Foot injection is a non-specific term, often used by patients, in reference to tarsal or metatarsal joint injections, and to other injections which include:​ calcaneocuboid joint injection metatarsophalangeal joint (MTPJ) injection naviculocuneiform joint injection plantar fascia microtenoto...
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Knee injection (disambiguation)

Knee injection is a general term and can be made in reference, especially by patients, to multiple procedures which include: common peroneal (fibular) nerve injection knee joint injection MRI arthrogram CT arthrogram anesthetic arthrogram patella tendon microtenotomy proximal tibiofibular...
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Long head of biceps brachii tendon sheath injection (technique)

Long head of biceps brachii (LHB) tendon sheath injections under ultrasound guidance ensure accurate delivery of injectate, which is important as these injections are often performed for diagnostic purposes.    Indications pain diagnostic injection alternative access to the glenohumeral join...
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Pain rating scales

There are a number of pain rating scales used by clinicians and researchers to gauge the severity of patients' pain. Commonly used methods: pain numeric rating scale (NRS/NPRS) visual analog scale (VAS) verbal rating scale (VRS) faces pain scale-revised (FPS-R) Pain numeric rating scale Th...
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On-track and off-track shoulder lesions

Bipolar shoulder lesions of anterior glenohumeral dislocations (i.e. combined bony Bankart lesions and Hill-Sachs defects) put patients at increased risk of Hill-Sachs engagement or recurrent instability. Determining if the Hill-Sachs defects are on-track or off-track can help guide management, ...
Article

Mulder sign

Mulder sign is a clinical test used to examine causes of metatarsalgia associated with Morton neuroma. It has high specificity (100%) but relatively low sensitivity (62%) 2. See the ultrasound correlate described separately: sonographic Mulder sign. Technique With one hand, clasp the metatarsa...
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Sonographic Mulder sign

The sonographic Mulder sign is the ultrasound correlate of the clinical Mulder sign during examination of the forefoot to investigate causes of metatarsalgia associated with Morton neuroma 1. The intermetatarsal space is predominantly composed of fat inferiorly and also contains the neurovascula...
Article

Lipoma vs well-differentiated liposarcoma

There a number of features that can help distinguish between lipoma and well-differentiated liposarcoma. This article relates to superficial well-differentiated liposarcomas that typically occur in the extremities, also known as atypical lipomatous tumors, and not retroperitoneal liposarcoma. E...
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Alpha angle (cam morphology)

The alpha angle is a radiological measurement proposed for the detection of cam morphology, which is sometimes associated with femoroacetabular impingement (FAI).  Terminology The term alpha angle is also used in a separate and unrelated context in the evaluation of developmental dysplasia of ...
Article

McMurray test

The McMurray test is used to assess the presence of meniscal tears within the knee. Background Clinical tests used for the detection of meniscal tears provide varying levels of diagnostic parameters including sensitivity and specificity. MRI is considered the most accurate diagnostic tool for ...
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Coarse trabecular pattern in bone (differentials)

Coarse trabecular bones can result from a number of causes. They include: Paget disease (bone) osteoporosis osteomalacia rickets hemaglobinopathies, e.g. thalassemia Gaucher's disease hyperparathyroidism   See also Coarse trabecular pattern in bone (mnemonic)
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Coracohumeral interval

The coracohumeral interval is usually measured on axial or oblique sagittal CT or MRI and normally measures between 7-11 mm. A measurement <6 mm is always considered abnormal 1. 
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Red and yellow flags for guiding imaging of lower back pain

Lower back pain (also known as lumbago) is very common and is often referred for imaging. However, the vast majority of cases are due to benign self-limiting causes which do not require imaging and resolve with conservative measures. Numerous authors have described various methods for supporting...
Article

Mass of the inguinal region (differential)

The differential diagnosis of a mass in the inguinal region includes: inguinal hernia femoral hernia hydrocele of the canal of Nuck spermatic cord hydrocele lymphadenopathy or necrotic lymph node aneurysm or pseudoaneurysm of the femoral artery iliopectineal bursa abscess hematoma lymp...
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Extrusion index

The extrusion index is a radiographic measurement of femoral head bony coverage by the acetabulum. It is useful in assessing for developmental dysplasia of the hip as well as femoroacetabular impingement. Measurement It is calculated by dividing the horizontal distance of the lateral femoral h...
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Ankle impingement syndromes

There are several ankle impingement syndromes. They are characterized by a limited range of motion and pain on attempting specific movements about the joint and often in a load-bearing position. They have variable etiology and pathogenesis. They are best classified according to location. The ke...
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Geographic appearance

Geographic appearance is a term used in imaging, and other clinical fields (e.g. histopathology) to describe lesions with a well-circumscribed margins with adjacent tissues.  The term derives from the somewhat similar appearance of the outline of countries on a map or the clear demarcation forme...
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Describing a bone lesion

Describing a bone lesion is an essential skill for the radiologist, used to form an accurate differential diagnosis for neoplastic entities, and occasionally non-neoplastic. In addition to patient demographics, the radiographic features of a bone lesion are often the primary determinant of non-h...
Article

Densitometric vertebral fracture assessment

Densitometric vertebral fracture assessment (VFA) is an image of the lumbar and thoracic spine acquired on dual energy x-ray absorptiometry (DXA) scanners, for the purpose of diagnosing osteoporotic vertebral fractures.  Terminology The technique is available on DXA scanners under a variety of...
Article

Magnetic resonance neurography

Magnetic resonance neurography (MRN) is a relatively new non-invasive imaging technique for dedicated assessment of peripheral nerves. It is used to assess peripheral nerve entrapments and impingements as well as localization and grading of nerve injuries and lesions. Dedicated high-resolution...
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Canadian C-spine rules

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...
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NEXUS criteria

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 require all of the following: alert and stable no focal neurologic de...
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Coronal balance

Coronal balance is one of the features that needs to be assessed on long spine radiographs obtained for spinal deformity, particularly scoliosis. It measures whether or not the upper spine is located over the midline (normal) or off to one side.  Measurement To assess coronal balance, a vertic...
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Sagittal balance

Sagittal balance forms part of the plain radiographic assessment of spinal deformity including kyphotic or lordotic deformities and scoliosis. Usage There are numerous ways of assessing this, using various bony landmarks and angles to evaluate whether or not a normal distribution of weight and...
Article

Central sacral vertical line

The central sacral vertical line (CSVL) is used in the assessment of spinal scoliosis.  It is a line constructed on frontal films of the spine and pelvis to measure coronal balance, drawn as follows: a line connecting the top of the iliac crests is drawn a second line is drawn perpendicular t...
Article

Shoulder radiograph (summary approach)

This is a basic article for medical students and other non-radiologists 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. Summary approach alignment...
Article

Wrist radiograph (summary approach)

This is a basic article for medical students and other non-radiologists Wrist radiographs are commonly used for the assessment of the wrist following trauma.  Summary approach alignment AP distal radius and ulna have smooth joint surface carpal arcs are smooth carpal bones do not overlap ...
Article

Amsterdam wrist rules

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...
Article

Subacromial bursal injection

Subacromial bursal corticosteroid injections, also known as subacromial-subdeltoid bursal injections, are used in patients with limited or no response to initial treatment with impingement syndrome, subacromial bursitis and/or rotator cuff disorders. Non-steroidal anti-inflammatory drugs (NSAIDs...
Article

Carpal height

Carpal height is used to diagnose and assess the severity of carpal collapse. It is defined as the distance between the base of third metacarpal and the subchondral bony cortex of the distal radius. But due to variations between individuals, it is more appropriate to calculate the carpal height ...
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

Iliofemoral line

The iliofemoral line is traced on an AP pelvis projection. It is a curvilinear line, along the outer surface of the ilium, through the superior acetabular rim and the femoral neck. It should be bilaterally symmetrical. Asymmetry may be the result of congenital dysplasia, slipped femoral capital...
Article

Ottawa ankle rules

The Ottawa ankle rules are a clinical decision-making strategy for determining which patients require radiographic imaging for ankle and midfoot 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...
Article

Investigation of polyarthritis (summary)

This is a basic article for medical students and other non-radiologists Polyarthritis (arthritis affecting several joints) is common, especially in older patients. Symptoms may range from mild pain and restriction to severe, debilitating disease with mutilated joints. Assessment Arthritis may...
Article

Wrist radiograph (approach)

Wrist x-rays are commonly used for the assessment of the wrist following trauma. This is usually a fall onto an outstretched hand. Systematic review It is useful to have a systematic approach; I tend to start proximally and work distally looking at structures on both views together: distal ra...
Article

Fluid-fluid levels in bone tumors

Fluid-fluid levels in bone tumors is a commonly encountered finding, both in benign as well as malignant bone tumors, and can be used to differentiate between the two. Measurement On the sagittal T2W image: measure the length of the largest fluid-fluid level (A) measure the maximum length of...
Article

Gissane angle

Gissane angle, also known as the "critical angle of Gissane", is a measurement on lateral foot radiographs used to evaluate the severity of calcaneal fractures. Measurement The Gissane angle is measured by drawing lines along the superior surfaces of the anterior process and the posterior face...
Article

Coxa magna

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.  Pathology Etiology Legg-Calve-Perthes disease transient synovitis...
Article

Coxa profunda

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 (Kohler's) line. Coxa profunda i...
Article

Coracoclavicular distance

The coracoclavicular (CC) distance is an indicator of the integrity of the coracoclavicular ligament. Measurement The coracoclavicular distance is assessed on frontal radiography of the shoulder or clavicle or the coronal projection of a CT or MRI as the distance between the superior cortex of...
Article

Describing a fracture (an approach)

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 radiograph What radiograph (or radiographs) are you looking at? Check the who, what, why, w...
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Tumors that metastasize to bone (mnemonic)

Tumors that metastasize to bone may be remembered using the mnemonic "PBKTL", rendered as "lead kettle", as "Pb" is the standard abbreviation for the chemical element, lead. PB-KTL Mnemonic P: prostate B: breast K: kidney T: thyroid L: lung For females, breast and lung are the most commo...
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Intermetatarsal angle

The intermetatarsal angle is a measurement used to assess hallux valgus and metatarsus primus varus deformities. Terminology The term intermetatarsal angle alone typically refers to assessment of the first and second metatarsals. Occasionally the term first intermetatarsal angle is used to spe...