Introducing a Knee Endoprosthesis Model Increases Risk of Early Revision Surgery

Abstract

Background New equipment and techniques often are used in clinical practice, occasionally without evidence of effectiveness and safety. Questions/purposes We asked whether the stage of introduction of an endoprosthesis model for TKA affected the risk of early revision. Methods We studied mandatory registry data from all centers in Finland (n = 69) that performed TKAs for primary osteoarthritis between 1998 and 2004. Of the total of 23,707 patients (28,760 TKAs), 22,551 patients (27,105 TKAs) had a followup of 5 years; we excluded longer followup from the analysis as subsequent revisions might result from wear rather than early technical failures. We used proportional hazards modeling for calculating the hazard ratios for the first 15 operations and subsequent increments of numbers of operations while adjusting for potentially confounding variables. Results For the first 15 operations with a new endoprosthesis, the risk was elevated (hazard ratio, 1.48; 95% confidence interval, 1.14-1.91). Absolute risk increase of early revision for the first 15 patients was 1.7% (95% confidence interval, 0.7-2.7). The risk was not increased as the numbers of TKAs incrementally performed increased. Conclusions Our data show an increased risk of early revision surgery for the first patients obtaining a knee endoprosthesis model previously unused in the hospital. Patients should be informed if there is a plan to introduce a new model of endoprosthesis in the hospital and offered the possibility to choose a conventional endoprosthesis instead.

The Uptake of New Knee Replacement Implants in the UK: Analysis of the National Joint Registry for England and Wales

“…Frequently changing implant brand may lead to poorer outcomes for patients through 3 routes. First, there may be a hospital-level learning curve effect after switching to a new implant brand in which the earliest patients to receive an implant are at elevated risk of early revision [24]. It is unknown whether the learning curve is weaker or stronger at the consultant-level.…”

Learning Curve for New Technology?

“…The personal identity number allows the linking of hospital discharge register data with implant register data individually for patient characteristics, operation details, and outcome. The first patients who received a new knee implant model in a hospital had an increased risk for early revision surgery 10 . However, it has not been known if at introduction all implants show a learning effect or whether this is a characteristic for only some knee implants.…”

“…When computerized navigation or a minimally invasive technique is implemented in total knee arthroplasty, studies have documented a learning curve effect [6][7][8][9] . There is also a higher risk for early revision total knee arthroplasty when a knee prosthesis is introduced into hospital practice 10 .…”

Elevated risk of early reoperation in total hip replacement during the stage of unit closure

“…For instance, it has been shown that introduction of a new hip or knee implant in a hospital entails a learning effect for the first 15 operations only (Peltola et al. 2012 , 2013 ), and the implementation of a new technique such as hip resurfacing entails a learning curve of around 25 operations (Nunley et al. 2010 )—or for anterior-supine minimally invasive THA, of around 40 operations (Seng et al.…”