Paper of the Week: Work Relative Value Units Do Not Adequately Support the Burden of Infection Management in Revision Knee Arthroplasty

Linsen T. Samuel, MD, MBA, Daniel Grits, BS, Alexander J. Acuña, BS, Nicolas S. Piuzzi, MD, Carlos A. Higuera-Rueda, MD, and Atul F. Kamath, MD

The Journal of Bone and Joint Surgery. 2020;102(3):230-236.
doi: 10.2106/JBJS.19.00776

Summary by Fortunato G. Padua, MD, MSc

As total knee arthroplasty becomes an increasingly common procedure in the United States [1], so too is the expected incidence of septic arthritis [2]. This complication not only increases the morbidity profile of patients while placing a greater burden on healthcare resources [3], it also leads to more complex surgical procedures [4]. Compared to primary total knee arthroplasty, revision total knee arthroplasty often requires multiple stages, more expensive implants, additional instrumentation, longer hospital stays and more extensive blood loss [5].

Samuel et al. sought to assess whether the increased hardship placed on surgeons who perform septic revision total knee arthroplasty is compensated for appropriately. To do this, the study compared the Relative Value Units (RVUs) under the Medicare reimbursement algorithm between septic and aseptic revision total knee arthroplasty. The authors of the study also compared RVUs per minute of work effort by including operative time in the analysis. From the American College of Surgeons National Surgical Quality Improvement Program (ACSNSQIP) database, 12,907 cases of aseptic revision, 891 cases of 1-stage septic revision, 293 cases of 1^st stage 2-component septic revision, and 279 cases of 2^nd stage 2-component septic revision procedures were identified.

The RVU per minute decreased from 0.215 for aseptic 2-component revision procedures to 0.199 for the septic, 2-component, 1-stage revision. RVUs per minute further decreased for septic 2-stage revisions: 0.157 for the first stage and 0.144 for the second stage. Mean operative time, on the other hand, increased from 149 minutes for aseptic revision cases to 161 minutes for septic 1-stage revision cases. For septic 2-stage revision procedures, mean operative time was 138 and 170 minutes for the first and second stage, respectively. Thus, as surgeons spent increasingly more work hours in the operating room for septic revision cases, they were not compensated proportionately to those who performed aseptic revision procedures.

Limitations of the study include the potential for coding errors during data acquisition and the lack of modifiers being encoded into the database. This study brings to light a potential inequity in the Medicare reimbursement algorithm with regard to septic revision total knee arthroplasty.

References:

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