LAUSR

Case: An 8-year-old boy with left lateral ankle pain was diagnosed with acute osteomyelitis after methicillin-susceptible Staphylococcus aureus was identified in a subperiosteal abscess in the distal fibula that had been aspirated using an ultrasound-guided needle. Symptoms improved after 2 weeks of intravenous and 4 weeks of oral antimicrobial therapy; no additional treatment was required. No growth retardation or sequelae were observed at the 6-year follow-up. Conclusions: In acute osteomyelitis, the identification of subperiosteal abscess is key for early diagnosis. Ultrasound evaluation of the distal fibula should also be considered in the diagnosis of lateral ankle pain in children.