Preoperative evaluations in revision total knee arthroplasty

Area of Science:

• Orthopedic Surgery
• Infectious Disease
• Diagnostic Accuracy

Background:

• Total knee arthroplasty (TKA) failure can stem from various causes, necessitating precise preoperative diagnosis for successful revision surgery.
• Accurate identification of infection (sepsis) is critical for managing septic TKA revisions.

Purpose of the Study:

• To evaluate the clinical value of common preoperative investigations in diagnosing sepsis in revision total knee arthroplasty.
• To compare the sensitivity, specificity, and predictive values of erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and cultures for diagnosing septic TKA failure.

Main Methods:

• Retrospective review of 295 patients undergoing revision total knee arthroplasty.
• Analysis of preoperative investigations including ESR, CRP, knee aspiration cultures, and intraoperative tissue cultures.
• Comparison of investigation results against the reason for revision (septic vs. aseptic).

Main Results:

• 26.8% of revisions were due to infection.
• ESR showed a sensitivity of 0.63 and specificity of 0.55.
• C-reactive protein (CRP) had a sensitivity of 0.60 and specificity of 0.63.
• Intraoperative tissue cultures demonstrated higher accuracy (0.83) with a specificity of 0.94.

Conclusions:

• No single preoperative investigation was sufficiently accurate to solely diagnose infection in revision TKA.
• Clinical judgment combined with routine tests like CRP, ESR, and knee aspiration provides predictable diagnostic insights.
• Intraoperative tissue cultures are crucial for definitive diagnosis of sepsis in revision total knee arthroplasty.