Prevalence of Complications Due to Transphyseal Hematogenous Osteomyelitis

Background:Transphyseal hematogenous osteomyelitis (THO) is a common infectious condition, being present in 25% of patients with hematogenous osteomyelitis. A large proportion of pediatric hematogenous osteomyelitis infections can spread through the growth cartilage and therefore may be potentially responsible for growth disorders, leading to limb-length discrepancy or angular deformities. The purpose of the present study was to identify both the prevalence of complications caused by transphyseal osteomyelitis and factors influencing their occurrence.Methods:The records for all patients who had been treated for THO over a 17-year period at the University Hospitals of Geneva and the Ges & ugrave; Bambino Hospital in Rome were retrospectively analyzed. Clinical, biological, and bacteriological data were analyzed. Magnetic resonance imaging (MRI) scans were reviewed for all patients to assess the cross-sectional area of growth plate involvement. Restart of growth of the affected physeal cartilage was subsequently monitored by means of iterative radiographic examination.Results:From a cohort of 594 patients with hematogenous osteomyelitis, 89 patients (15.0%) were found to have THO. The median age was 84 months (range, 1 to 167 months), with a bimodal distribution and peaks at 30 and 150 months; 59.6% (53) of the 89 patients were male. The lower limbs were most often affected, with the distal tibia and fibula accounting for 47.2% of all cases. Methicillin-sensitive Staphylococcus aureus and Kingella kingae were the most frequently identified pathogens, accounting for 61.8% of the cases. Virulence factors, such as Panton-Valentine leukocidin (PVL), toxic shock syndrome toxin (TSST), and accessory gene regulator (Agr), were recorded in 12.4% of MSSA strains. Transphyseal lesions affected a median of 7.6% (range, 0.79% to 58.2%) of the physeal surface. Complications affecting further growth were noted in 13% of patients with THO. Thrombocytopenia, leukocytosis, and the presence of virulence factors significantly influenced the occurrence of complications.Conclusions:THO affects all age categories of the pediatric population. In the present study, growth disturbance occurred in 13% of cases. The presence of deep thrombocytopenia, leukocytosis, and virulence factors, such as Agr, TSST, and PVL, seems to strongly influence the occurrence of such complications.Level of Evidence:Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.