Musculoskeletal Infection and Complications
Core rules
- Acute osteomyelitis and septic arthritis need urgent aspiration or debridement plus culture before antibiotics when feasible.
- Staphylococcus aureus is the commonest pathogen; biofilm makes chronic infection resistant to antibiotics alone.
- Periprosthetic joint infection requires a diagnostic pathway: history, examination, inflammatory markers, aspiration and multiple tissue samples.
- Open fractures and contaminated wounds need tetanus assessment, antibiotics, debridement and stabilization.
- Chronic osteomyelitis may need dead-bone excision, dead-space management and prolonged targeted antibiotics.
Worked example
A 70-year-old with a total knee replacement has persistent pain and swelling six months after surgery. Reasoning: do not assume loosening; check CRP and ESR, aspirate before antibiotics, send synovial fluid for cell count and culture, and discuss debridement with implant retention versus revision based on chronicity and organism.
Traps
Do not give antibiotics before cultures unless the patient is septic. Do not diagnose infection on a single test. Do not forget fungal or mycobacterial causes in indolent infection.
Key points are listed separately.