Osteomyelitis in elderly patients.

In elderly persons, osteomyelitis is second only to soft-tissue infection as the most important musculoskeletal infection. Acute osteomyelitis is usually acquired hematogenously, and the most common pathogen is Staphylococcus aureus. Acute osteomyelitis can usually be cured with antimicrobial therapy alone. In contrast, chronic osteomyelitis may be caused by S. aureus but is often due to gram-negative organisms. The causative organism of chronic osteomyelitis is identified by culture of aseptically obtained bone biopsy specimens. Because of the presence of infected bone fragments without a blood supply (sequestra), cure of chronic osteomyelitis with antibiotic therapy alone is rarely, if ever, possible. Adequate surgical debridement is the cornerstone of therapy for chronic osteomyelitis, and cure is not possible without the removal of all infected bone.