Treatment for Septic Knee

Initial Management

The American College of Radiology considers septic arthritis an orthopedic emergency as bacterial proliferation can rapidly cause cartilage damage 3
Obtain appropriate microbiologic cultures (joint fluid, blood) before starting antimicrobial therapy, but do not delay antibiotics more than 45 minutes, as recommended by the Intensive Care Medicine society 4, 5
Administer broad-spectrum IV antibiotics within one hour of diagnosis to cover all likely pathogens, according to the Intensive Care Medicine guidelines 4, 6
Perform surgical drainage of the joint as soon as possible, as suggested by the Clinical Infectious Diseases society 1, 2

Drainage or debridement of the joint space should always be performed, as recommended by the Clinical Infectious Diseases society 1

Initial empiric antibiotics should include IV vancomycin (for possible MRSA coverage), as suggested by the Clinical Infectious Diseases society 1, 2
Consider adding a second agent for gram-negative coverage, according to the Intensive Care Medicine guidelines 4
Duration of therapy: 3-4 weeks is suggested for uncomplicated septic arthritis, as recommended by the Clinical Infectious Diseases society 1, 2
Longer courses (4-6 weeks) may be needed for patients with slow clinical response, according to the Intensive Care Medicine guidelines 6

For MRSA infections: IV vancomycin is the first-line treatment, as suggested by the Clinical Infectious Diseases society 1, 2
For pediatric patients: IV vancomycin is recommended for acute hematogenous MRSA, according to the Clinical Infectious Diseases society 2

Perform clinical examinations several times per day, as recommended by the Intensive Care Medicine society 7
Monitor inflammatory markers (ESR, CRP) to guide response to therapy, according to the Clinical Infectious Diseases society 1

Delayed diagnosis and treatment significantly worsen outcomes - each hour delay in antibiotic administration increases mortality, as reported by the Critical Care Medicine society 8