We present a case of a 71-year-old woman with unexplained instability of her total hip arthroplasty 12 years after implantation due to loosening of the ceramic component of a sandwich ceramic in polyethylene liner. She experienced in total 2 dislocations in 6 months. These events occurred without fracture of the ceramic liner. Sandwich ceramic liners were introduced with the idea of combining t...

Existing theories describe corrosive wear in crosshead diesel engines in terms of acid condensation, when the temperature in the combustion space drops below the dew point. Here a theory is proposed which stresses the role of alkaline cylinder lubricants in protecting the metal surface. Calculated liner wear rates as a function of fuel sulphur content, feed rate and alkalinity of the oil, and a...

A running-in and starved lubrication experiment is designed to investigate the heavy-duty scuffing behavior of piston ring coatings against cast iron (Fe) cylinder liner using the piston ring reciprocating liner test rig. The scuffing resistance of the piston ring with the chromium-based ceramic composite coating (CKS), and that with the thermally sprayed nickel-chromium-molybdenum coating (NCM...

We carried out a clinical and radiological review of 103 cementless primary hip arthroplasties with a tapered rectangular grit-blasted titanium press-fit femoral component and a threaded conical titanium acetabular component at a mean follow-up of 14.4 years (10.2 to 17.1). The mean Harris hip score at the last follow-up was 89.2 (32 to 100). No early loosening and no fracture of the implant we...

Soft bearing materials that aim to reproduce the tribological function of the natural joint are gaining popularity as an alternative concept to conventional hard bearing materials in the hip and knee. However, it has not been proven so far that an elastic cushion bearing can be sufficiently durable as a long term (∼20 years) articulating joint prosthesis. The use of new bearing materials should...

BACKGROUND AND PURPOSE There have been few reports documenting the wear and oxidation performance of the polyethylene bearing surface of HGPI and HGPII THA devices. We evaluated retrieved HGPI and HGPII acetabular liners that had been in situ for more than 10 years and determined whether there was a relationship between clinical and radiographic factors, surface damage, wear, and oxidation. M...

Metallosis and metal-induced synovitis are well-recognized complications of metal-backed polyethylene joint prostheses and have been frequently described in the orthopedic surgery literature; however, relatively fewer articles discussing the radiologic aspects of this complication have been published. To illustrate the importance of radiologic findings in the diagnosis and management of these p...

OBJECTIVE The goals of this study were 1) to better define the labial microflora and 2) to evaluate whether extended non-menstrual use of panty liners would increase genital carriage of undesirable bacteria and predispose to infection. METHODS Healthy female volunteers (224) were prospectively randomized into panty liner wear groups A (Always((R)) deodorant) and B (Always((R)) non-deodorant) ...

Locking mechanisms and metal-liner interface surfaces of six modular acetabular systems were evaluated to determine their effect on micromotion and backside wear of the polyethylene liner. Rotational and axial motion between the metal shell and polyethylene liner was measured in the Duraloc (DePuy, Warsaw, IN), Harris-Galante (Zimmer, Warsaw, IN), Impact (Biomet, Warsaw, IN), Lip Loc (Biomet), ...

We present a case of an 85-year-old woman with extensive metallosis of the left hip joint secondary to prosthetic polyethelene liner dislocation and wear. Radiographs demonstrated amorphous cloudy radiodensities surrounding the prosthesis, a feature we have called the "cloud sign." The presence of amorphous cloudy radiodensities as a radiographic sign of metallosis has not been previously descr...