Original research Comparison of adverse events rates and hospital cost between customized individually made implants and standard off-the-shelf implants for total knee arthroplasty Steven D. Culler, PhD a, * , Greg M. Martin, MD b , Alyssa Swearingen, BA c a Department of Health Policy and Management, Rollins School of Public Health, Emory University, Atlanta, GA, USA b Preferred Orthopedics of the Palm Beaches, Boynton Beach, FL, USA c Columbia University, New York, NY, USA article info Article history: Received 6 December 2016 Received in revised form 8 March 2017 Accepted 4 May 2017 Available online 9 June 2017 Keywords: Adverse event rate Hospital cost Length of stay Customized individually made implant TKA abstract Background: This study compares selected hospital outcomes between patients undergoing total knee arthroplasty (TKA) using either a customized individually made (CIM) implant or a standard off-the-shelf (OTS) implant. Methods: A retrospective review was conducted on 248 consecutive TKA patients treated in a single institution, by the same surgeon. Patients received either CIM (126) or OTS (122) implants. Study data were collected from patients' medical record or the hospital's administrative billing record. Standard statistical methods tested for differences in selected outcome measures between the 2 study arms. Results: Compared with the OTS implant study arm, the CIM implant study arm showed significantly lower transfusion rates (2.4% vs 11.6%; P ¼ .005); a lower adverse event rate at both discharge (CIM 3.3% vs OTS 14.1%; P ¼ .003) and 90 days after discharge (CIM 8.1% vs OTS 18.2%; P ¼ .023); and a smaller percentage of patients were discharged to a rehabilitation or other acute care facility (4.8% vs 16.4%; P ¼ .003). Total average real hospital cost for the TKA hospitalization between the 2 groups were nearly identical (CIM $16,192 vs OTS $16,240; P ¼ .913). Finally, the risk-adjusted per patient total cost of care showed a net savings of $913.87 (P ¼ .240) per patient for the CIM-TKA group, for bundle of care including the preoperative computed tomography scan, TKA hospitalization, and discharge disposition. Conclusions: Patients treated with a CIM implant had significantly lower transfusion rates, fewer adverse event rates, and were less likely to be discharged to a rehabilitation facility or another acute care facility. These outcomes were achieved without increasing costs. © 2017 The Authors. Published by Elsevier Inc. on behalf of The American Association of Hip and Knee Surgeons. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/). Introduction Osteoarthritis (OA) of the knee generates a substantial economic burden within the US health care system [1,2]. Total knee arthro- plasty (TKA) is relatively common and estimates indicate over 650,000 TKA procedures will be performed annually in the United States through 2030 [3]. TKA is associated with low mortality rates and treats OA effectively. Approximately 80%-90% of patients who undergo TKA report clinically significant improvement in pain and functional outcome [4-9]. Although an effective procedure, TKA and its associated hospital resource utilization accounted for $3.5 billion of reimbursement from the Medicare Program in the fiscal year 2011 [10]. A portion of these expenditures are generated by the infrequent, but significant, effects of major adverse events after TKA which add substantially to hospital treatment cost (the risk- adjusted cost of treating adverse events range between $30,900 [pneumonia] and $2200 [hemorrhage or postoperative shock requiring transfusions]) [11]. TKA procedures primarily use implants that are off-the-shelf (OTS) devices constructed with standard fixed sizes. The use of OTS implants requires the surgeon to make adjustments to fit the The authors do not have any proprietary interest in the material describe in this article and did not receive any grant support for this research. One or more of the authors of this paper have disclosed potential or pertinent conflicts of interest, which may include receipt of payment, either direct or indirect, institutional support, or association with an entity in the biomedical field which may be perceived to have potential conflict of interest with this work. For full disclosure statements refer to http://dx.doi.org/10.1016/j.artd.2017.05.001. * Corresponding author. 1518 Clifton Road, NE, Atlanta, GA 30322, USA. Tel.: þ1 404 727 3170. E-mail address: sculler@emory.edu Contents lists available at ScienceDirect Arthroplasty Today journal homepage: http://www.arthroplastytoday.org/ http://dx.doi.org/10.1016/j.artd.2017.05.001 2352-3441/© 2017 The Authors. Published by Elsevier Inc. on behalf of The American Association of Hip and Knee Surgeons. This is an open access article under the CC BY-NC- ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Arthroplasty Today 3 (2017) 257e263