Radiographic Imaging in the Postanesthesia Care Unit is Unnecessary After Partial Knee Arthroplasty

Obtaining routine radiographs in the postanesthesia care unit (PACU) after primary uncomplicated partial knee arthroplasty (PKA) is a common practice with unclear utility. The objective of this study is to determine the rate at which immediate postoperative radiographs identify an actionable problem after primary uncomplicated PKA and to determine the potential cost savings associated with foregoing the routine acquisition of these radiographs.

This was a retrospective review that assessed a consecutive series of 1366 primary uncomplicated PKAs (including 873 unicondylar knee arthroplasties, 313 patellofemoral arthroplasties, and 180 bicompartmental knee arthroplasties) performed between January 2008 and March 2016. Patients were separated into 2 cohorts: (1) those who had PACU radiographs (n = 1184), and (2) those who did not (n = 182). Operative reports and clinical follow-up records at the initial postoperative visit were reviewed to determine whether patients underwent early reoperation based on radiographic findings. The direct cost of PACU radiographs was estimated to be $33.63 based on average global Medicare payments from our institution.

The rate of reoperation because of radiographic findings in the PACU or at the first follow-up was 0% (95% confidence interval: 0.0%-0.027%). The estimated direct radiographic expenditure for our 1366 patient cohort was nearly $46,000.

Routine immediate postoperative PACU radiographs after primary uncomplicated PKA have limited clinical utility. Therefore, delaying postoperative radiographs until the initial follow-up office visit would result in substantial cost-savings without compromising the quality of patient care.