Comment on the X-ray

Ref. Textbook of Orthopedics, Ebnezar. Page.527   Brodie abscess is an intraosseous abscess related to a focus of subacute pyogenic osteomyelitis Typically these present in children with unfused epiphyseal plates, more frequently in boys.  S. aureus (most common); cultures often negative The “penumbra sign” on magnetic resonance (MR) imaging is useful for discriminating subacute osteomyelitis from other bone lesions. The penumbra sign is a rim lining of an abscess cavity with higher signal intensity than that of the main abscess on T1-weighted images