More than 99% of X-rays after knee replacement are unnecessary, costing healthcare millions

More than 99% of X-rays after total knee replacement surgery appear to be unnecessary, costing the healthcare system millions, according to a new analysis.

Gathering radiographs following this operation is common practice, but there is little data on the usefulness of these exams, experts wrote in The Knee. Wanting to better understand this practice, Brigham and Women’s scientists analyzed postoperative data across two level 1 trauma centers.

Their results were eye opening: Almost 100% of scans after total knee arthroplasty had no impact on clinical management after the procedure. Yet, these routine radiographs cost some $1 million while administering 22.92 mSV of radiation to patients who didn’t require such imaging.

“Since the majority of postoperative radiographs didn’t change clinical management and constituted a significant portion of follow-up care costs, methods to circumscribe unnecessary postoperative radiographs may be an effective cost-saving alternative, while simultaneously increasing the quality of TKA follow-up care by limiting radiographs to nonroutine follow-up visits,” Aseal Birir, an MD candidate at Harvard Medical School, and co-authors wrote Aug. 26.

Researchers conducted their retrospective study by pinpointing adult patients who underwent a knee replacement surgery across two centers in 2014. A total of 1,258 met the study’s criteria, at an average age of 72. Providers collected 3,831 X-rays following these operations, of which 1.1% contained a positive radiographic finding and 0.3% (or 13 exams) had a positive orthopedic finding. Eleven of those findings prompted changes in managing the patient post-surgery. Birir et al. estimated the cost for such scans using the average Medicare reimbursement rate for three-view knee radiographs ($99) and the hospital’s standard charge ($465), averaging out to $282 apiece per X-ray.

The authors noted that 91% of those 11 useful radiographs were collected during a nonroutine post-op visit, a key clue for refining patient management strategies.

“Further work developing evidence-based guidelines using nonroutine visits for determining the appropriateness of radiographs after primary TKA may be helpful to limit healthcare spending and support virtual postoperative visits after TKA,” the authors advised.

Marty Stempniak

Marty Stempniak has covered healthcare since 2012, with his byline appearing in the American Hospital Association's member magazine, Modern Healthcare and McKnight's. Prior to that, he wrote about village government and local business for his hometown newspaper in Oak Park, Illinois. He won a Peter Lisagor and Gold EXCEL awards in 2017 for his coverage of the opioid epidemic. 

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