Osteomyelitis

From Ganfyd

Osteomyelitis is technically inflammation of the bone and its marrow cavity (c.f. osteitis). This is nearly always due to bacterial infection. These bacteria may gain entry to the bone by either metastatic haematogenous spread or local invasion. Osteomyelitis has a propensity to become chronic and may present as a chronic, non-healing wound or sinus.

Organisms

• Staphylococcus aureus (90%)
• Haemophilus influenzae
• Salmonella
  • complicates Sickle-cell disease
• Mycobacterium tuberculosis
  • termed Pott's disease if involves spine

Treatment

• immobilisation
• appropriate antibiotics
  • a common regime is six-weeks intravenous therapy
  • Flucloxacillin with Fusidic acid is an obvious choice because the organism is typically Staph aureus. Sodium fusidate (the tablet form) has excellent penetration into bone and may be given orally because it has very good bioavailability via this route (fusidic acid, the suspension form less so). It must never be given on its own because of the risk of resistance arising.
• surgery
  • if sequestrum (dead bone within pus-filled cavity) drainage/laying open may allow infection to clear
  • reconstruction with muscle flaps may bring additional vascularity into the area and allow an effective immune response

These infections can be difficult if not impossible to eradicate because of the presence of bone and the difficulty in penetrating it with antibiotics.