Retained Foreign Objects after TJA Surgery Have Clinical and Financial Consequences

    A study from the OrthoCarolina Research Institute estimates the annual number of total hip and total knee arthroplasty patients who will have a retained foreign object after surgery – designated a “never event” – and the cost to the health system.

    Each year, nearly 100 total joint arthroplasty (TJA) patients will have a foreign objects left in their body following surgery, at an estimated average cost of more than $6,000 per patient, according to a study from the OrthoCarolina Research Institute that was recently reported at the annual meeting of the International Society for Pharmacoeconomics and Outcomes Research.

    Although that’s a very small percentage – approximately 0.01% – of the number of TJA procedures performed annually, it’s significant for 2 reasons:

    • Patient morbidity: In the study, patients with a retained surgical item (RSI) had to undergo 1 additional procedure, on average, than patients without an RSI (P<0.0001). That extends their length of stay and puts them at greater risk for complications, including infection and deep vein thrombosis.
    • Hospital reimbursement: The Centers for Medicare and Medicaid Services (CMS) has designated RSI as a “never event.” So when a never event occurs in a Medicare or Medicaid patient, the hospital is not reimbursed for that patient’s care. Many private insurance companies have adopted the never event model as well – which could lead to a lot of unreimbursed care.

    Data for the study were obtained from the 2009-2012 National/Nationwide Inpatient Samples (NIS). The researchers identified TJA patients by the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) procedure codes 81.51 (hip TJA) and 81.54 (knee TJA), and those who had a retained foreign object, such as surgical instruments and sponges, by the ICD-9-CM codes 998.4 and 998.7, as well as the ICD-9-CM external causes of injury code, E871.0.

    They calculated the national incidence estimate by using the NIS sample weights, and they estimated costs with the NIS charge-to-cost ratio for each hospital. The study reports costs in 2015 dollars using Consumer Price Index adjustment for inflation.

    More than 29 million surgical procedures were performed during the study period. Of those 761,214 (2.61%) were TJA procedures.

    The researchers found 1 RSI per 6,878 total hip arthroplasty (THA) procedures and 1 RSI per 11,961 total knee arthroplasty (TKA) procedures. That’s 0.01% of all TJA procedures and 3.16% of all surgical procedures for which the hospital reported an RSI.

    Using those numbers, they estimated that 43 THA patients and 52 TKA patients will have an RSI annually. The cost of this avoidable event, the researchers said, is an estimated $6,412 per patient.

    It should be noted that these estimates may be low: The data used by the researchers provided information on RSIs identified only during the initial hospitalization. Data on RSIs identified after discharge were not available in the NIS database.

    “Despite considerable effort aimed at reducing the frequency in which foreign objects are inadvertently left in the body during surgery, these avoidable events continue to occur in TJA,” the researchers said. “While retained objects are rare events in TJA, these adverse events lead to excess cost and procedural burden for patients.”

    The federal government’s recent repeal of Medicare’s Sustainable Growth Rate (SGR) payment formula in favor of a merit-based payment system will put more emphasis on the value of care versus the volume of care, the researchers noted.

    That means orthopaedic surgeons who eliminate never events such as a retained foreign object can expect to be rewarded under the new system. Those who do not can expect financial penalties not only from CMS, but possibly also from the private insurance payers they accept.


    Van Doren BA, Odum SM, Curtin B. Hospital-reported frequency & excess cost of foreign objects left in the body during total joint arthroplasty. Presented at the International Society for Pharmacoeconomics and Outcomes Research 20th Annual International Meeting, May 16-20, 2015, in Philadelphia, Pennsylvania.