16 Year Registry Data for Cross-Linked Poly

While the results of this study may not surprise, 16 years of data covering more than 240,000 implants is worth adding to the decades of data on this particular issue.

The study, “Cross-Linked Polyethylene for Total Hip Arthroplasty Markedly Reduces Revision Surgery at 16 Years,” appears in the August 1, 2018 edition of The Journal of Bone and Joint Surgery.

Professor Richard de Steiger of the Australian Orthopaedic Association National Joint Replacement Registry and School of Public Health at the University of Adelaide and study co-author recalled some of the reasons manufacturers and physicians moved away from conventional polyethylene in the 1990s by noting: “This topic was of particular interest because for many years wear of the polyethylene bearing surface of total hip arthroplasty (THA) was responsible for bone lysis and eventual loosening of joint replacements. The issues with regards to wear limited the long-term success of THA and particularly for younger patients undergoing THA.”

“We performed an observational study of data, from a national registry, on all patients who underwent THA for osteoarthritis in Australia from 1999 through December 31, 2016. The outcomes of THAs performed with non-cross-linked polyethylene were compared with those of THAs performed with cross-linked polyethylene, along with an analysis of the effect of age, sex, femoral head size, the method of acetabular and femoral component fixation, and the reasons and types of revision…non-cross-linked polyethylene was used in 41,171 procedures, and cross-linked polyethylene was used in 199,131…”

Professor de Steiger said, “The most important results were that patients who had cross-linked polyethylene compared to conventional polyethylene had a much lower rate of revision, particularly for loosening of the components and lysis and wear. There was also a reduction in prosthesis dislocation but that was related to surgeons having the confidence to use larger head sizes with cross-linked polyethylene which we know reduces the rate of dislocation following THA.”

“The important finding from this work is cross-linked polyethylene should be the bearing of choice in an acetabulum if the surgeon is deciding to use any type of polyethylene. As demonstrated in the article this is true in Australia with over 97% of patients having primary THA with polyethylene had a cross-linked polyethylene bearing inserted.”

“Surgeons can be confident that the use of larger head sizes such as 32mm and 36mm are not showing an increase in wear related symptoms with cross-linked polyethylene. when larger head sizes were used with conventional polyethylene there was increased revision for wear.”

“We were also able to show that in younger, higher demand patients (under 55 years of age) cross-linked polyethylene had a much lower rate of revision compared to conventional polyethylene at up to 15 years follow up. These data may be used to inform younger patients undergoing primary THA that they are less likely to have a revision in the longer term with the use of cross-linked polyethylene.”