Authors: Greber E, Edwards P, Bushmiaer M, Wilson B, Barnes CL.
Arkansas Specialty Orthopedics, Little Rock, AR
Title: Is Screening for Periprosthetic Joint Infections Using ESR and CRP per AAOS Clinical Practice Guidelines Cost Effective?
Background: Until recently, there has been no consensus of the best approach to differentiating aseptic from septic loosening in joint replacement patients. The recent AAOS Clinical Practice Guideline Summary that was published in 2010, tasks orthopedic surgeons with the strong recommendation of obtaining ESR and CRP for all patients needing hip and knee arthroplasty revision surgery and aspirating the joint based upon these results.
Hypothesis/Purpose: The purpose of this study is to determine from our patients whether this guideline has been helpful and cost effective in determining periprosthetic joint infections.
Methods: We retrospectively reviewed charts of 50 consecutive patients who underwent revision total hip or knee arthroplasty. Each patient received an ESR and CRP level prior to operation and patients with known periprosthetic joint infections were excluded from the study. As guidelines recommend, aspiration with cultures and cell count were obtained on all knees with either elevated ESR or CRP and all hips with both ESR and CRP elevated. We then determined how many patients needing revision arthroplasty of the hip or knee benefited from ESR, CRP, and aspiration by finding subclinical periprosthetic infection and changing the intraoperative treatment. Hospital charge data was used to report cost of this protocol.
Results: Sixty-four percent (32/50) patients had elevated ESR and/or CRP. Eighteen patients (12 hips; 7 knees) required joint aspirations per the guidelines. None of the aspirations were positive for bacterial growth.
Discussion: The total hospital charges for aspiration and cultures in this patient population were $81, 712.44. No sub clinical infection was identified.
Conclusion: Although guidelines may more readily diagnose every case of subclinical joint infection, we must continue to evaluate the cost of this type protocol in a busy revision practice.