A Comparison of Relative Value Units in Primary Versus Revision Total Knee Arthroplasty.

BACKGROUND: In total knee arthroplasty (TKA), revision cases are often technically more challenging, and require more operative time and aftercare than primary cases. These time and effort differences should therefore be appropriately compensated for when using the relative value unit (RVU) system. Therefore, the purpose of this study is to compare the mean (1) RVUs; (2) operative times; and (3) RVU/min; and (4) perform an individualized idealized surgeon annual cost difference analysis for primary vs revision TKA.

METHODS: Current Procedural Terminology code 27447 identified 165,439 primary TKA patients, while Current Procedural Terminology code 27487 identified 8081 revision TKA patients from the National Surgical Quality Improvement Program database. The mean RVUs, operative times, and RVU/min were calculated. Dollar amount per minute, per case, per day, and year were also calculated. Student's t-test, with a cut-off P-value of <.05, was used in order to identify any statistical differences in mean RVUs, operative times, and RVU/min.

RESULTS: The mean RVUs for primary TKA was 22, while for revision TKA was 27 (P < .001). The mean operative time for primary TKA was 94 minutes, while for revision TKA was 149 minutes (P < .001). The mean RVU/min for primary TKA was 0.26, while for revision TKA was 0.22 (P < .001). The dollar amounts calculated for primary vs revision TKA were per minute ($9.33 vs $7.90), per case ($877.12 vs $1176.43), per day ($4385.60 vs $3529), and projected a $137,008.70 annual cost difference.

CONCLUSION: Orthopedic surgeons are reimbursed at a higher rate per minute for primary cases compared to revision TKA (0.26 vs 0.22, P < .001). The annual difference can amount to nearly $140,000. Orthopedic surgeons can use this information to better understand the dynamics of their time, compensation, and ultimately, their practice. Furthermore, it can be argued that there needs to be a shift to increase the RVU per unit time for revision TKAs.