Review Question - QID 210218

Acute osteomyelitis with a subperiosteal abscess should be treated with irrigation and debridement followed by a period of intravenous antibiotics.

Pediatric osteomyelitis occurs often following a hematogenous spread of bacteria that seeds the sluggish metaphyseal venous sinusoids. The diagnosis can be confirmed with a combination of physical exam, laboratory tests, and imaging studies. Treatment algorithms vary but it is generally agreed upon that if a patient has worsening physical exam findings, lab tests, and imaging studies following a trial of antibiotics for 48 hours, surgical decompression is indicated. If purulence collects below the periosteum, the osteogenic cells within the periosteum may be destroyed leading to a limited regenerative capacity and subsequent bone defects. Once the decision for surgery is made, all purulence and necrotic tissue should be debrided and excised including any dead or necrotic bone.

Johnston et al. reviewed 102 cases of acute hematogenous osteomyelitis in children over an 11-year period. They found a delay in presentation was not associated with abscess formation and 78% of all bone abscesses were seen on initial MRI. They conclude the consistent and early use of MRI may identify abscesses in acute hematogenous osteomyelitis.

McCarthy et al. reviewed musculoskeletal infections in children including acute hematogenous osteomyelitis. They state that the treatment principles for osteomyelitis are similar to other infections, identifying the correct offending organism, directed antibiotic therapy, and surgical treatment for cases refractory to medical management.

Figure A and B show an AP and lateral of a skeletally immature foot with no signs of fracture or periosteal reaction. Figures C and D show a sagittal and coronal T2 MRI with increased signal intensity in the first metatarsal and a proximal and lateral subperiosteal abscess. Illustration A shows the same sagittal and coronal MRI images with red arrows indicated the location of the subperiosteal abscess.

Incorrect Answers:
Answer 1: Immobilization and continued oral antibiotics would likely be unsuccessful as he has worsened on a course of oral antibiotics.
Answer 2: Immobilization and intravenous antibiotics is unlikely to be effective in the setting of a subperiosteal abscess.
Answer 4 & 5: Wide resection and chemotherapy would not be indicated as this presentation is consistent with infection