Quantifying and Predicting Surgeon Work Effort for Primary and Revision Total Knee Arthroplasty.

Background: The objectives of this study were to quantify increased utilization of resources in revision total knee arthroplasty (TKA) compared with primary TKA, determine preoperative factors that predict outcome measures, and compare Medicare reimbursement for each procedure.

Methods: Seventy-eight revision TKA patients were compared with 80 primary TKA patients. Outcomes measured were surgical time, estimated blood loss, length of stay, and complications.

Results: Revision TKA showed 49% increased surgical time compared with primary TKA. Estimated blood loss was increased 91%. Tibial and femoral bone loss was associated with increased surgical time as was use of longer stemmed tibial components. Average Medicare hospital payment increased 29% ($13,464 for primary, $17,331 for revision). Average physician reimbursement represented a 36% increase. Relative value units were increased to 31%.

Conclusion: There was substantial increase in work effort not commensurate with current Medicare reimbursement, which may limit patient access to revision TKA.