Neonatal Osteomyelitis

  • Etiology: hematogenous spread from asymptomatic or symptomatic bacteremia or by direct extension from skin wound, infection starts in marrow space with significant edema with proliferation of excess WBC and bacterial growth and through bony canals the infected fluid permeates outward and elevates the periosteum
  • Imaging: most commonly occurs at metaphysis and metaphyseal equivalents (apophyses, areas at the junction of bone and cartilage in flat bones) both of which are highly vascular with slow blood flow, before epiphyseal ossification centers appear (18 months) infection can cross growth plate into epiphysis as there is free communication between vessels of epiphysis and metaphysis and these transphyseal vessels can serve as a path of spread of infection from metaphysis to epiphysis, infection can spread into joint space / subperiosteal space / soft tissues / diaphysis of bone, most common regions involved are extremities and pelvis, continuous periosteal reaction, deep soft tissue edema, cutaneous abscesses
  • Complications: subperiosteal abscess, intramedullary abscess
  • Clinical: more common in preterm, multifocal in 25%

Radiology Cases of Neonatal Osteomyelitis

Radiograph of neonatal osteomyelitis
AP radiograph of the right humerus at presentation (left) is unremarkable. AP radiograph of the right humerus 1 month later (right) shows destruction and medial displacement of the epiphysis of the humerus and extensive periosteal reaction along the metaphysis and diaphysis of the humerus.