Abstract
New technology in joint replacement design and materials adds cost which must be documented by improved outcomes. This is not always the case as the recent metal/metal data has shown. The current economics of arthroplasty surgery have put increasing financial pressure on hospitals and will progress under new health care legislation. New technology must be cost effective and this will be increasingly difficult in an era of outstanding long term results with current designs. Cost may necessitate less expensive alternatives, e.g. generic implants, in arthroplasty patients.
Joint replacement surgery has evolved over the past four decades into a highly successful surgical procedure. Earlier designs and materials which demonstrated inferior functional and long term results have disappeared in a Darwinian fashion. Through this evolutionary process many of the current designs have proven efficacy and durability. Current outcome data indicates that hip and knee designs demonstrate 90–95% success rates at 15 year follow-up. Technologic advances are necessary to improve implant design and materials, however, in an environment of reduced reimbursement to hospitals can the increase cost be justified.
The rationale that technology in medicine would be expensive at the outset yet be cost effective eventually has in many areas not been the case. Currently about one half of the rapid increase in health care costs in relation to GNP may be attributed to technology. Uwe Reinhardt, an economist at Princeton University, in referring to new technology has stated that the health care system provides misaligned incentives that create over-utilisation or misutilisation of everything that is new. It is now common knowledge among health care economists that if the cost of health care is to be controlled the growth of technology must be constrained.
Increasingly as new technology emerges the question will be: what is the cost-benefit analysis. A new era of comparative effectiveness research is being launched and will become predominant in medicine and arthroplasty surgery in the future. What is the newest may not always be the best. According to Reinhardt there is a need for comparative effectiveness studies of emerging and existing technology so that the new can be priced in a way that reflects its incremental value. New technology must demonstrate its benefit to justify its cost, often in arthroplasty there is little data available to document these better outcomes.
In a recent study by Bozic the cost effectiveness of new technologies were evaluated. Based on the authors' findings for an alternative bearing with an incremental cost of $2000 to be cost saving for a 50 year old there would have to be a 19% reduction in 20 year failure rates. The likelihood of cost savings for these alternate bearings in patients 63 or older is highly unlikely at current costs. Newer biomaterials (metal/metal, ceramic/ceramic, highly cross linked polyethylene) also have limited outcome analysis in patients beyond short to mid-term follow-up evaluation and all of these technologies add significant cost to the implant. With diminishing reimbursement careful analysis of utilisation of these newer technologies must be weighed if hospitals are to maintain economic viability.
The pharmaceutical, airline, and food industries have all moved toward generic products which are less costly and this will be the trend in the future in prosthetic implants as well. Newer technologies must demonstrate their efficacy in long term follow-up and be clearly superior to conventional implants. This is not always the case as new data on metal-metal implants is demonstrating. Change is not always progress.
