van Loon J, Hoornenborg D, Sierevelt I, Opdam KT, Kerkhoffs GM, Haverkamp D. Highly cross-linked versus conventional polyethylene inserts in total hip arthroplasty, a five-year Roentgen stereophotogrammetric analysis randomised controlled trial. World J Orthop 2020; 11(10): 442-452 [PMID: 33134107 DOI: 10.5312/wjo.v11.i10.442]
Corresponding Author of This Article
Daniël Haverkamp, MD, PhD, Surgeon, Department of Orthopaedic Surgery, Xpert Orthopedie Amsterdam/Specialized Center of Orthopedic Research and Education, Laarderhoogtweg 12, Amsterdam 1101EA, Netherlands. d.haverkamp@xpertorthopedie.nl
Research Domain of This Article
Orthopedics
Article-Type of This Article
Randomized Controlled Trial
Open-Access Policy of This Article
This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
World J Orthop. Oct 18, 2020; 11(10): 442-452 Published online Oct 18, 2020. doi: 10.5312/wjo.v11.i10.442
Highly cross-linked versus conventional polyethylene inserts in total hip arthroplasty, a five-year Roentgen stereophotogrammetric analysis randomised controlled trial
Justin van Loon, Daniël Hoornenborg, Inger Sierevelt, Kim TM Opdam, Gino MMJ Kerkhoffs, Daniël Haverkamp
Justin van Loon, Daniël Hoornenborg, Inger Sierevelt, Daniël Haverkamp, Department of Orthopaedic Surgery, Xpert Orthopedie Amsterdam/Specialized Center of Orthopedic Research and Education, Amsterdam 1101EA, Netherlands
Justin van Loon, Kim TM Opdam, Gino MMJ Kerkhoffs, Department of Orthopaedic Surgery, Amsterdam University Medical Centres, Location Academic Medical Center, Amsterdam 1105AZ, Netherlands
Author contributions: All authors contributed to the study conception and design. Haverkamp D and Hoornenborg D were involved in the initial surgery procedures; writing of the study protocol was performed by Haverkamp D; data collection and analysis were performed by van Loon J and Sierevelt IN; the first draft of the manuscript was written by van Loon J; all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.
Institutional review board statement: This single center RCT was granted ethical approval by the local ethics committee review board of Slotervaart Hospital (NL23524.048.08).
Clinical trial registration statement: This study is registered at the Dutch Trial Register. The registration identification number is NL5605.
Informed consent statement: All study participants, or their legal guardian, provided informed written consent prior to study enrollment.
Conflict-of-interest statement: The authors declare that there is no conflict of interest.
Data sharing statement: No additional data are available.
CONSORT 2010 statement: The design and reporting of this study were carried out in accordance with the Consolidated Standards of Reporting Trials (CONSORT) principles (see attached CONSORT checklist).
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Daniël Haverkamp, MD, PhD, Surgeon, Department of Orthopaedic Surgery, Xpert Orthopedie Amsterdam/Specialized Center of Orthopedic Research and Education, Laarderhoogtweg 12, Amsterdam 1101EA, Netherlands. d.haverkamp@xpertorthopedie.nl
Received: May 19, 2020 Peer-review started: May 19, 2020 First decision: May 26, 2020 Revised: June 3, 2020 Accepted: August 25, 2020 Article in press: August 25, 2020 Published online: October 18, 2020
Abstract
BACKGROUND
Polyethylene (PE) particles produced by wear of the acetabular insert are thought to cause osteolysis and thereby aseptic loosening of the implant in total hip arthroplasty (THA). As highly cross-linked polyethylene (HXLPE) is presumed to give lower wear rates, in vivo studies are needed to confirm this.
AIM
To compare the wear of REXPOL, a HXPLE, with conventional PE within the first five years after implantation using Roentgen stereophotogrammetric analysis (RSA).
METHODS
Patients were randomised to receive either a HXLPE (REXPOL) or a conventional PE insert during primary THA. RSA images were obtained directly postoperative and after 6 wk, 12 wk, 6 mo, 12 mo, 24 mo and five years. Functional outcomes were assessed using the Hip Injury and Osteoarthritis Outcome Score and Harris Hip Score at baseline and five years after surgery.
RESULTS
The HXLPE (REXPOL) showed less wear in the latero-medial direction. Significant wear rates of conventional PE were seen in the latero-medial and center-proximal direction and in volume and corrected volume, whereas the REXPOL did not show these outcomes over time. Improvement from baseline in functional outcome did not significantly differ.
CONCLUSION
Total 3D wear is less in THAs inserted with a REXPOL inlay than a conventional PE inlay after five years. This study confirms, for the first, that the REXPOL HXLPE inlay is preferred to standard PE.
Core Tip: Polyethylene (PE) particles produced by wear of the acetabular insert can cause osteolysis and thereby aseptic loosening of the implant in total hip arthroplasty (THA). As highly cross-linked polyethylene (HXLPE) is presumed to result in lower wear rates, we performed a randomised controlled trial (RCT) using Roentgen stereophotogrammetric analysis with a five-year follow-up period. This RCT showed, for the first time, that five-year total 3D wear was less in THAs inserted with REXPOL HXLPE and hereby confirms that this inlay is preferred to standard PE.
