Document Detail

Continued improved wear with an annealed highly cross-linked polyethylene.
MedLine Citation:
PMID:  20844996     Owner:  NLM     Status:  MEDLINE    
BACKGROUND: Highly cross-linked polyethylene (HXLPE), created by disrupting the molecular structure of polyethylene, then through the application of heat, encourages creation of new cross-links in the process, resulting in a material with improved wear resistance. The impetuses for this new technology were the unsatisfactory wear properties and subsequent osteolysis of noncross-linked polyethylene. A 72% reduction in wear using highly cross-linked polyethylenes (HXLPE) compared with conventional polyethylene at 5 years was described previously. The longest term followup studies on HXLPE range from 2 to 6 years.
QUESTIONS/PURPOSES: We therefore addressed the following questions: (1) Does the improvement in wear observed at the earlier followup continue to 7 to 10 years? (2) What is the incidence of osteolysis in this group of patients and in the control group?
METHODS: We retrospectively reviewed 38 prospectively followed patients who had 42 hips with an annealed HXLPE who were followed a minimum of 7 years (average, 8.6 years; SD=1; range, 7-10.3 years). Wear and osteolysis were compared with those of a control group of 39 patients (40 hips) from a US Investigational Device Exemption (IDE) prospective, randomized study begun in 1996 with conventional polyethylene and followed for a minimum of 6 years (average, 7.5 years; SD=1.1; range, 6-10.2 years). Linear head penetration was measured from AP radiographs at early, 1-year, 5-year, and most recent followups.
RESULTS: At the average followup, annual linear wear was 0.031 mm (SD=0.014) for the HXLPE and 0.141 mm (SD=0.080) for the control group, a 78% reduction. No mechanical failure of the polyethylene was noted in either group. Incidence of osteolysis was 50% in the control group (all lesions confined to proximal Gruen Zones 1 and 7) compared with no cases in the investigational group.
CONCLUSIONS: We observed an improvement in wear and no mechanical failures with this annealed material.
LEVEL OF EVIDENCE: Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
William N Capello; James A D'Antonio; Rama Ramakrishnan; Marybeth Naughton
Related Documents :
19473806 - Third-generation ceramic-on-ceramic bearing surfaces in revision total hip arthroplasty.
17016216 - Hydroxyapatite-coated femoral components: 15-year minimum followup.
2047106 - Healing of periapical radiolucencies after nonsurgical endodontic therapy.
8134276 - Clinical evaluation of trans-tibial prosthesis sockets: a comparison between cad cam an...
12783106 - Enoxaparin monotherapy without oral anticoagulation to treat acute symptomatic pulmonar...
6974786 - Changes in coronary bypass surgery leading to improved survival.
Publication Detail:
Type:  Comparative Study; Journal Article     Date:  2010-09-16
Journal Detail:
Title:  Clinical orthopaedics and related research     Volume:  469     ISSN:  1528-1132     ISO Abbreviation:  Clin. Orthop. Relat. Res.     Publication Date:  2011 Mar 
Date Detail:
Created Date:  2011-02-03     Completed Date:  2011-03-24     Revised Date:  2013-05-27    
Medline Journal Info:
Nlm Unique ID:  0075674     Medline TA:  Clin Orthop Relat Res     Country:  United States    
Other Details:
Languages:  eng     Pagination:  825-30     Citation Subset:  AIM; IM    
Indiana University School of Medicine, 541 Clinical Drive, Suite 600, Indianapolis, IN 46202, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Arthroplasty, Replacement, Hip / instrumentation*,  methods
Cross-Linking Reagents
Equipment Failure Analysis
Femur Head / radiography
Hip Prosthesis*
Indiana / epidemiology
Middle Aged
Osteolysis / epidemiology,  etiology*
Polyethylenes* / chemistry
Prosthesis Design
Prosthesis Failure / adverse effects*
Randomized Controlled Trials as Topic
Retrospective Studies
Surface Properties
Reg. No./Substance:
0/Cross-Linking Reagents; 0/Polyethylenes

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Is rituximab superior to cyclophosphamide for ANCA-associated vasculitis for induction of remission,...
Next Document:  Hip offset in total hip arthroplasty: quantitative measurement with navigation.