Presentation
Left sided hip pain for about 4 weeks. No red-flag symptoms.
Patient Data
Age: 5 years
Gender: Male
From the case:
Perthes disease
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Info
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Frog-leg view of both hips. Asymmetry with loss of the normal appearance of the left proximal femora. There is coxa magna (metaphyseal widening) and loss of the femoral epiphysis with sclerosis, lucency and fragmentation.
Case Discussion
Appearances here are of avascular necrosis. In this age-group, when there is no other cause (e.g. steroid treatment, sickle cell disease), Perthes disease (idiopathic AVN) is the diagnosis.
AVN here has been progressing for a while and the acute history do not match the imaging findings.