Articles
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176 results found
Article
Superscan
A superscan is an imaging appearance on a Tc-99m diphosphonate bone scan which occurs as a result of a high ratio of bone to soft tissue tracer accumulation. Intense osteoblastic activity in the bones causes diminished renal and background soft tissue uptake.
Pathology
Etiology
This appearanc...
Article
Bent bone dysplasias (differential)
Bent bone dysplasias are a class of skeletal dysplasia included in a 2010 classification of genetic skeletal disorders 1:
campomelic dysplasia
Stuve-Weidemann dysplasia
kyphomelic dysplasias, a diverse class, including
congenital bowing of the long bones
cartilage-hair hypoplasia (CHH; meta...
Article
Rib notching
Rib notching refers to deformation of the superior or inferior surface of the rib. It can affect a single rib (from trauma or solitary masses e.g. schwannoma) or can affect multiple ribs.
Differential diagnosis
The differentials differ according to whether it is the superior or inferior surfac...
Article
Leave alone lesions - skull base
Leave alone lesions of the skull base refers to incidental findings that do not require treatment nor follow-up.
This article includes findings from brain CT, HRCT of the temporal bone, and MRI studies.
Do not touch:
arrested pneumatization of the skull base - sphenoid benign fatty lesion 1
...
Article
Synovial enhancement
Synovial enhancement is an imaging feature typically observed on MRI imaging. It can occur in various forms and can be focal or diffuse.
Pathology
inflammatory
synovitis
transient synovitis of the hip
infective synovitis
inflammatory arthritides
septic arthritis
tuberculous septic arthri...
Article
Diffuse T1 bone marrow signal loss
Diffuse T1 vertebral bone marrow signal loss is associated with replacement of fatty marrow by edema or cellular tissue.
Radiographic features
MRI
T1-weighted imaging without fat suppression is one of the most important sequences for distinguishing between normal and abnormal bone marrow. Ab...
Article
Erosive arthritis (differential)
Erosive arthritis has a broad differential:
erosive osteoarthritis
clinically an acute inflammatory attacks (swelling, erythema, pain) in postmenopausal women
typically the interphalangeal joints, 1st carpometacarpal joint 6, but not the metacarpophalangeal (MCP) joints and large joints
clas...
Article
Patella baja
Patella baja, also known as patella infera, is an abnormally low lying patella, which is associated with restricted range of motion, crepitations, and retropatellar pain. If longstanding, extensor dysfunction may ensue with significant morbidity.
Pathology
It is seen in a variety of clinical s...
Article
Single layer periosteal reaction
Single layer (or lamellar) periosteal reaction is a uniformly dense, single thin layer of new bone about 1-2 mm from the cortical surface. It usually denotes an acute or subacute pathological process. Passive hyperemia causes increased osteoblastic activity and production of new bone.
Pathology...
Article
Multilayered periosteal reaction
Multilayered periosteal reaction, also known as a lamellated or onion skin periosteal reaction, demonstrates multiple concentric parallel layers of new bone adjacent to the cortex, reminiscent of the layers on an onion. The layers are thought to be the result of periods of variable growth 2 and ...
Article
Disorganized periosteal reaction
Disorganized or complex periosteal reaction has spicules with random orientation and appearance. It is often seen in highly aggressive processes.
Pathology
It has been associated with:
osteosarcoma
metastasis
osteomyelitis
chondrosarcoma
Ewing sarcoma
stress fracture
malignant fibrous h...
Article
Periosteal reaction
Periosteal reaction is a nonspecific radiographic finding that indicates new bone formation in reaction to the abnormal stimulants. Periosteal reactions may be broadly characterized as benign or aggressive, or more specifically categorized by pattern.
Terminology
Periosteal reaction is the rec...
Article
High bone mineral density
A high bone mineral density is one where the bone mineral density (BMD) is usually greater than two standard deviations above what is expected for age. This can sometimes be seen on routine DEXA scan assessment. Some authors advocate a definition of a high BMD where the Z-score is greater than +...
Article
High riding shoulder
A high-riding shoulder refers to the superior displacement/subluxation of the humeral head with resultant decrease in the acromiohumeral distance.
The differential for a high-riding shoulder is:
rotator cuff tear with or without rotator cuff arthropathy
rheumatoid arthritis: rheumatoid arthri...
Article
Leave alone lesions - maxillodental
Maxillodental leave alone lesions are usually incidental findings that do not require treatment nor follow-up if the patient is asymptomatic.
This article includes findings from orthopantomogram, cone-beam CT, and sinus CT studies.
Do not touch:
benign lesions
tooth ankylosis
hypercementosi...
Article
Terminal tuft mass
There is only a short list of terminal tuft masses that can arise from the adjacent soft tissues and erode the terminal tuft or arise from the terminal tuft itself:
epidermal inclusion cyst: history of penetrating trauma
tenosynovial giant cell tumor: occurs laterally
subungual glomus tumor (...
Article
Sclerosing bone dysplasia (overview)
Sclerosing bone dysplasias comprise a heterogeneous group of disorders (skeletal dysplasias) united by the presence of sclerosis of one form or another:
craniodiaphyseal dysplasia
craniometaphyseal dysplasia
Buschke-Ollendorff syndrome
hereditary multiple diaphyseal dysplasia (Ribbing disea...
Article
Sclerotic bone metastases
Sclerotic or osteoblastic bone metastases are distant tumor deposits of a primary tumor within bone characterized by new bone deposition or new bone formation.
Epidemiology
Bone metastases are the most common malignancy of bone of which sclerotic bone metastases are less common than lytic bone...
Article
Craniovertebral junction anomalies
Craniovertebral junction (CVJ) anomalies can be congenital, developmental or due to malformation secondary to an acquired disease process. These anomalies can lead to cranial nerve compression, vertebral artery compression, and obstructive hydrocephalus.
Pathology
The craniovertebral junction ...
Article
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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