Abstract
Introduction:
The prevalence of total hip (THA) and knee arthroplasty (TKA) is growing dramatically, with more than 1 million procedures performed annually in the United States. As the cost of and demand for the newest orthopaedic implants continue to rise, the price paid to medical device companies for implants is a growing concern. Some high-volume healthcare institutions have adopted price capitation strategies to control costs, in which a flat purchase price is negotiated for all implant line items regardless of technology and material. The purpose of this study was to evaluate whether the implementation of price capitation in a large health system affected trends in THA and TKA premium implant selection by surgeons. A secondary objective was to compare selection trends between surgeons with an academic center affiliation and community practice surgeons, within a single health system.
Methods:
All consecutive primary THA and TKA cases six months before (1/1/2011–6/30/2011) and after (8/1/2011–1/31/2012) implementation of a capitated pricing strategy (7/1/2011) were identified. Surgeon education regarding the new pricing policy was conducted for 1-month following implementation, and data during this time were omitted from the study. After exclusions (Figure 1), a total of 481 THA and 674 TKA from the large hospital, and 253 THA and 315 TKA from the two community hospitals comprised the final study cohort. A retrospective review of patient demographics and implant characteristics for each case was performed. Premium THA implants were defined by the existence of one of the following bearing surfaces: second (2G) or third generation (3G) highly cross-linked polyethylene liner with a ceramic or oxidized-zirconium femoral head, ceramic liner with a ceramic femoral head, or mobile-bearing system. Premium TKA implants were defined by the existence of at least one of the following criterion: mobile-bearing design, high-flexion design, oxidized-zirconium femoral component, and/or highly cross-linked polyethylene bearing surface. Pearson's chi-square analyses and Fisher's exact test were used to compare implant usage between pre- and post-capitated pricing time periods.
Results:
Surgeons with an academic center affiliation increased premium THA implant usage from 65.77% to 70.27% (p = 0.29), while surgeons at the community hospitals selected fewer premium implants (36.36%) and did not change their practice (p = 0.80) (Figure 2). TKA implant usage with one or more premium criteria increased from 73.37% to 89.54% (p < 0.001) for surgeons with an academic affiliation (Figure 3). Premium TKA implants (particularly mobile-bearing) were used at greater rates by our community hospital surgeons before and after price capitation, with all TKA implants having at least one premium criteria. While there was a significant increase in the use of high-flexion knee systems by community hospital surgeons (p = 0.03) following price capitation, there was an unexpected decrease in use of highly cross-linked polyethylene (p = 0.03).
Conclusions:
These results highlight the effect of price capitation on implant selection by academically affiliated and community practice surgeons. There was a clear trend towards premium implant usage in TKA with price capitation, particularly for surgeons with an academic practice. No differences were detected in premium THA implant selection for either group of surgeons.
