The purpose of this paper is to demonstrate the imaging characteristics of Blount-disease on conventional radiography and magnetic resonance imaging (MRI).
To illustrate the specific measurements and classification system of Morbus Blount with pictorial examples.
To discuss the role of imaging in the diagnosis,
staging and therapy planning of the disease.
Blount-disease is characterized by disorganized enchondral ossification (osteochondrosis) of the medial portionof the epiphyseal and metaphyseal areas of the proximal tibia .
The exact etiology is unknown,
but there is strong association with childhood obesity,
which suggests a mechanical background.
There is an inbalance between the nutritional needs of the growing bone [2,
Risk factors for Blount-disease:
ethnicity or race - higher incidence in children of African origin
gender - more common in females
genetics - autosomal dominant and recessive form
Findings and procedure details
Role of conventional radiology:
first modality of choice in the evaluation of the knee (a,
Langenskiöld staging; b,
a.) Langenskiöld stages areage dependent progressive stages,
based on the degree of depression of the medial plateau [1,
Stage I.: BEAK,
medial metaphyseal beaking
Stage II.: SAUCER,
saucer shaped defect ofthe medial metaphysis
saucer deepens into step
Stage IV.: BENT PLATE,
epiphysis bent down...
Blount-disease refers toadeforming osteochondrosis of the medial aspect of the proximal tibia,
juvenile and late onset types,
based on the age and the clinical onset of the disease.
Conventional radiography is a fundamental tool in the diagnosis,
staging and surgical planning of Blount-disease.
Radiologists should be familiar with the Langenskiöld-stages,
the normal values and age-dependent changes of the meta-diaphyseal and tibiofemoral angle.
at an early age,
differentiating Blount-disease from physisologic bowing is not easy.
Observation and follow-up imagesmight unravel the differential diagnostic...
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