chronic osteomyelitis

Introduction

also see osteomyelitis

Clinical manifestations

• frequently presents as subacute or chronic pain over affected bone
• fever & other systemic symptoms uncommon
• may underlie pressure ulcers & other chronic wounds not responding to therapy

Complications

• bone penetration of antibiotics is low
  • bone/plasma concentration ratio maximizes at ~0.3
• long-term antibiotic treatment often requires implantation of a central venous catheter that exposes the patient to intravenous catheter-related infections & thrombotic complications

Management

• combined medical & surgical approach
  • aggressive surgical debridement followed by a prolonged course of targeted antibiotic(s)
  • adequate surgical debridement with removal of all dead & ischemic tissue & sinus tracts is key
  • only curative strategy is wide surgical excision including healthy bone & soft tissues
  • local excision & debridement is associated with high failure rates
  • complete removal of infected bone & biofilm facilitates vascular supply & antibiotic access
  • additional components of surgery that contribute to treatment success include
    • management of dead space (bone defect after debridement &/or wide surgical excision)
      • muscle flaps, bone grafts, calcium hydroxyapatite implants)
    • stabilization of bone
    • wound site coverage with skin grafts
• intravenous antibiotics have been the standard after adequate surgical management
  • antibiotics that achieve the highest bone to serum concentration ratios
    • fluoroquinolones, sulfamides, cyclines, macrolides, rifamycins, & oxazolidinones are also those with the highest oral bioavailability, thus good candidates for prolonged outpatient treatment of chronic osteomyelitis
    • no significant difference between oral vs parenteral antibiotics if bacteria are sensitive to the antibiotic used
  • combination therapy in selected cases may reduce possibility of selecting resistant organisms &/or add activity on biofilm
• delaying start of antibiotic treatment until bone culture, identification of the causative organism & antimicrobial sensititities is standard of care in treating chronic osteomyelitis

More general terms

• osteomyelitis
• chronic infection (chronic infectious disease)