Brodie’s Abscess

  • Etiology: Staphylococcus aureus most common, subacute osteomyelitis which can persist for years before converting to frank osteomyelitis
  • Imaging: radiolucent center with reactive sclerosis + surrounding granulation tissue, lucent channel extending to physis is pathognomonic, sclerotic rim on radiograph fades away
  • MRI: penumbra sign – central pus, enhancing granulation (penumbra), bone sclerosis (dark on all MRI sequences), surrounding marrow edema
  • Clinical: may present with draining abscess

Cases of Brodie’s Abscess

Radiograph of osteomyelitis with Brodie's abscess
AP radiograph of the knee at presentation (upper left) shows lucent lesions of the metaphysis and epiphysis which show some interval healing on a followup AP radiograph of the knee taken 2 months later (upper right). The patient was lost to followup and did not complete antibiotic therapy and returned to clinic 2 years later and the AP radiograph at that time (lower left) shows a lucent sinus tract extending from the epiphysis to the metaphysis that persists on the next AP radiograph of the knee obtained 1 year later (lower right).