Author(s): Paul Krogstad
Osteomyelitis is an infection localized to bone. It is usually caused by microorganisms (predominantly bacteria) that enter the bone hematogenously. Other pathogenic mechanisms include direct inoculation (usually traumatic, but also surgical), or local invasion from a contiguous infection (eg, cellulitis, sinusitis, periodontal disease). Other risk factors for nonhematogenous osteomyelitis include open fractures that require surgical reduction, implanted orthopedic hardware (such as pins or screws), and puncture wounds.