INTRODUCTION: Radiation cross-linking is used to decrease wear in ultra high molecular weight polyethylene (UHMWPE) as a total joint arthroplasty bearing surface [1,2] but it also reduces its fatigue strength [1]. Current research focus is to improve the fatigue strength of wear and oxidation resistant cross-linked UHMWPEs in order to improve their use in high stress applications and young and ...

BACKGROUND Charnley low-friction torque total hip arthroplasty (THA) remains the gold standard in THA. The main cause for failure is wear of the socket. Highly crosslinked polyethylene (HXLPE) has been associated with reduced wear rates. Also, oxidized zirconium has shown in vitro reduced wear rates. However, to our knowledge, there are no data comparing oxidized zirconium femoral heads with me...

Introduction: Crosslinking of polyethylene has been known for decades to improve the abrasion resistance of the polymer for industrial applications. However, only three applications of this technology have been reported in use in total hip replacements in the orthopaedics literature by Grobbelaar et. al. [1], Oonishi et. al. [2], and Wroblewski et. al. [3]. Recently, the interest in highly cros...

in the present work, a titanium-based ziegler-natta catalyst was employed to synthesize ultra molecular weight polyethylene in a slurry medium. the effect of different parameters such as ethylene pressure, temperature, catalyst composition, and hydrogen pressure was studied. as the results indicate, increasing either [al]/[ti] ratio or temperature causes polymerization rate to go through a maxi...

The silver salts of fatty acids were studied as precursors for the preparation of colloidal dispersions of silver nanoparticles and UHMWPE (ultra-high-molecular-weight polyethylene) composite with silver nanoparticles, as well as the composition, the spectra and SEM (scanning electron microscopy) results. keywords: Silver laurate, silver palmitate, ascorbic acid, differential scanning spectrosc...

For the first time, an ultrathin type of ultra-high molecular weight polyethylene (UHMWPE) membrane only 350 nm thickness is surface modified by direct fluorination and plasma treatments. Then a notable suppression in crystallinity observed. A total four kinds thickness, from to 6 µm, are investigated correlate modification effect on thickness. Microscopically, continuous shish-kebab structure ...

Since polyethylene is one of the most frequently used biomaterials as a liner in total hip arthroplasty, strong efforts have been made to improve design and material properties over the last 50 years. Antioxidants seems to be a promising alternative to further increase durability and reduce polyethylene wear in long term. As of yet, only in vitro results are available. While they are promising,...

Use of larger diameter femoral heads has emerged as a promising strategy to reduce the risk of dislocation after total hip arthroplasty, but thinning the walls of cross-linked ultra-high-molecular-weight polyethylene (UHMWPE) acetabular liners to accommodate these larger heads may compromise the locking mechanism of the liner. The purpose of this study was to test the mechanical integrity of th...

The temporal change of the direction of sliding relative to the ultrahigh molecular weight polyethylene (UHMWPE) component of prosthetic joints is known to be of crucial importance with respect to wear. One complete revolution of the resultant friction vector is commonly called a wear cycle. It was hypothesized that in order to accelerate the wear test, the cycle frequency may be substantially ...

In more than 90% of hip replacements, the acetabular cup is made ultra-high molecular weight polyethylene (UHMWPE) and femoral head stainless steel, cobalt-chromium-molybdenum alloys, titanium or ceramic. The primary factor in evaluating soft-on-hard endoprostheses maximum contact pressure as strength UHMWPE. level these pressures used a criterion for correct selection size radial clearance con...