How Has THA Implant Usage Changed Since 2001? (AAOS 2014)
According to a study presented yesterday by Kevin J. Bozic, MD, MBA, data on total hip arthroplasty (THA) from 2001 to 2012 reveal significant trends in THA implant usage in the United States—including a strong preference toward cementless fixation.
In addition, the data show a trend toward the use of metal-on-polyethylene or ceramic-on-polyethylene bearings, modular acetabular cups, and large diameter femoral heads. Metal-on-metal and ceramic-on-ceramic constructs have declined in popularity, as have resurfacing procedures. Dr. Bozic linked these declines to concerns about increased wear debris and subsequent osteolysis.
Because the demand for THA continues to increase, said Dr. Bozic, orthopaedic surgeons must have “a thorough understanding of the comparative effectiveness, including costs and clinical outcomes, associated with various THA implant designs.”
Assessing the data
The investigators evaluated data from the Orthopaedic Research Network (ORN), which contains data on orthopaedic procedures compiled on an ongoing basis from 174 hospitals across the country. For the purposes of this study, 105,291 THA procedures performed from 2001 to 2012 were assessed for fixation, bearing choice, acetabular cup and liner choice, and femoral head implant use.
“Since 2001, the biggest change in the mix of constructs for primary THA has been an increase in the use of cementless components for both the femoral stem and the acetabular cup,” said Dr. Bozic. The percentage of cementless THAs performed each year rose from 46 percent in 2001 to 93 percent in 2012.
In 2012, 56 percent of primary THA bearings were metal-on-highly cross-linked polyethylene (HXLPE), while 35 percent were ceramic-on-HXLPE. The use of metal-on-metal bearings dropped from 37 percent in 2007 to less than 1 percent in 2012.
Nearly all (99 percent) acetabular cups used in 2012 were modular, up from 77 percent in 2007. Vitamin E-enhanced HXLPE was used in 13 percent of liners.
Data on femoral heads showed a decline in the use of metal (61 percent in 2012, down from 96 percent in 2001) and an increase in the use of ceramic (39 percent in 2012, up from 4 percent in 2001).
Although only 4 percent of femoral heads were larger than 32 mm in 2001, 66 percent were 36 mm or greater in 2012. Since 2005, when the average selling price (ASP) for hip implants increased from $3,000 to $5,500, implant prices have stabilized, as evidenced by an ASP of $6,920 in 2012, representing just a 3.7 percent price increase from 2011.
One possible limitation of this study is that hospitals providing data to the ORN are self-selected, and thus may not be nationally representative. However, informal surveys have suggested that the ORN’s data reflect nationwide trends.
Dr. Bozic’s coauthor for Scientific Paper 255 is Mandeep Lehil, BS.
Details of the authors’ disclosures as submitted to the Orthopaedic Disclosure Program can be found in the Final Program; the most current disclosure information may be accessed electronically atwww.aaos.org/disclosure
2014 Annual Meeting News
Tuesday through Friday, March 11 – 14, 2014.
http://www.aaos.org/news/acadnews/2014/AAOS18_3_13.asp