Do survival rate and serum ion concentrations 10 years after metal-on-metal hip resurfacing provide evidence for continued use?

Background: Owing to concerns attributable to problems associated with metal-on-metal bearing surfaces, current evidence for the use of hip resurfacing is unclear. Survival rates reported from registries and individual studies are controversial and the limited long-term studies do not conclusively allow one to judge whether hip resurfacing is still a reasonable alternative to conventional THA.

Questions/purposes: We asked whether the long-term survival rate of hip resurfacing is comparable to that of conventional THA and certain factors can be identified that influence serum ion concentration 10 years postoperatively.

[Acetabular revision surgery with the oblong revision cup : clinical and radiological results of 217 cases].

Background: Deficiencies of the acetabular bone stock are an increasing and challenging problem in revision hip surgery. The LOR oblong revision cup is a valuable option in revision hip surgery. The purpose of this study was to assess outcomes with the LOR revision cup in hips with acetabular bone deficiency, analyze the complications, and identify predictors of survival rate.

Short-term outcome after posterior versus lateral surgical approach for total hip arthroplasty - A randomized clinical trial.

Purpose: Currently, total hip replacement (THR) is most commonly performed via a posterior or a direct lateral approach, but the impact of the latter on the invention's outcome has yet not been quantified.

Methods: We compared the short-term outcome of cementless THR using the both approaches in a prospective, randomized controlled trial. 60 patients with unilateral osteoarthritis were included.

In vivo wear rate of the Birmingham Hip Resurfacing arthroplasty. A review of 10 retrieved components.

The wear of 8 femoral and 2 acetabular components of the Birmingham Hip Resurfacing (Midland Medical Technologies Ltd, Birmingham, UK) was measured using a coordinate measuring machine (CMM5; SIP, Geneva, Switzerland). After a median in situ time of 13 months, measurements of the Birmingham Hip Resurfacing femoral heads revealed a median volumetric wear of 2.9 mm(3).

[Revision surgery of hip resurfacing].

Early results of contemporary hip resurfacing are encouraging and consequently an increasing number of this procedure has been performed worldwide. A theoretical advantage of hip resurfacing is that failed components can be revised safely and successfully revised to a conventional total hip arthroplasty. As the number of systematically analyzed failures is still limited, however, current data from the literature cannot substantially support this assumption.

Birmingham Hip Resurfacing arthroplasty: short-term clinical and radiographic outcome.

Background: Aim of our study was to evaluate the clinical and radiographic outcome of the first 300 consecutively implanted Birmingham Hip Resurfacing arthroplasties (BHR) in our department.

Methods: 300 BHR arthroplasties were performed in 263 patients until May 2003. Primary clinical endpoints of the investigation were the implant survival and the total Harris hip score, assessed at the last examination.

[Clinical pathways. A useful steering instrument or a limitation for medical treatment?].

Clinical pathways can be used to organize the optimal sequence for medical procedures. This process is patient centered and developed through the collaborative work of the participating medical specialties. The goals of clinical pathways are facilitation of outcomes, reduction of variance in patient care and cost containment.

Neo-capsule tissue reactions in metal-on-metal hip arthroplasty.

Background: Modern-generation metal-on-metal articulations have a high wear resistance and may therefore be able to improve the long-term performance of artificial joints. However, the biological effects are still under debate. This study was undertaken to review the histopathological changes in neo-capsule tissues of different metal-on-metal hip arthroplasties.

Serum metal ion exposure after total knee arthroplasty.

All metal implants release metal ions because of corrosion. This has been studied and debated, especially in metal-on-metal total hip arthroplasties. Total knee arthroplasty implants have large metal surface areas and therefore substantial potential for corrosion.

[Results for endoprosthetic care in patients younger than 50 years].

Arthroplasty has become the most successful surgical procedure in developed countries. Replacement of severely damaged joints results in a substantial relief of pain, as the main symptom of osteoarthritis, in the majority of treated patients. With improved results in endoprosthetic surgery over the last decades, however, patients are increasingly undergoing the procedure to enhance their functional capacity and physical mobility.

[Necrosis of the femoral head in late pregnancy. Necessity of early diagnosis].

Limping and groin pain can issue diagnostic problems during late pregnancy. Differential diagnosis of two idiopathic syndromes, transient osteoporosis and osteonecrosis of the femoral head, is made possible by MRI in the early stages. This case is reported to demonstrate the need to distinguish between those syndromes early so as to prevent further joint damage.

Exposure to chromium, cobalt and molybdenum from metal-on-metal total hip replacement and hip resurfacing arthroplasty.

Background: All metal implants--and metal-on-metal bearings in particular--corrode and cause a release of metal ions. Because cobalt and chromium have been shown to be carcinogenic and mutagenic in human and animal models, systemic toxicity and cancer risk are considered to be possible disadvantages of the metal-on-metal articulation. This study was designed to investigate the serum concentration profiles of chromium, cobalt and molybdenum after implantation of a Birmingham hip resurfacing arthroplasty (BHR) and a cementless total hip replacement with a 28-mm Metasul articulation (MTHR), over the first 2 years after implantation.

[Resurfacing arthroplasty of the hip].

Currently, an increase in resurfacing arthroplasty in the treatment of hip osteoarthritis--especially in young adults--can be observed. New bearing technologies (mainly metal-on-metal surfaces) show better tribologic results than historical designs (e.g.

[Hip resurfacing arthroplasty].

In comparison to stemmed total hip replacements, hip resurfacing offers advantages especially in joint stability and amount of femoral bone resection. After the poor results achieved with this concept that were mainly caused by failure of the materials used, reintroduction of the metal-on-metal bearing initiated a renaissance. This bearing, the cementless cup, and the improved surgical technique led to better short- to medium-term results.

[Functional results after surface replacement of the hip: comparison between dysplasia and idiopathic osteoarthritis].

Aim: To determine if there are differences in function after resurfacing arthroplasty of the hip in patients with primary osteoarthritis compared to patients with secondary osteoarthritis due to developmental dysplasia of the hip.

Method: In a controlled prospective study of Birmingham Hip Resurfacing (BHR) we included all patients with primary osteoarthritis (n = 54, average age 48.4 years) and osteoarthritis due to high grade dysplasia (Eftekhar B, n = 34, average age 55.

[Urinary concentration of collagen metabolites in endoprosthesis loosening].

Aseptic loosening is the most common long-term complication in arthroplasty. Loosening is in every case associated with bone resorption at the interface that leads to bone defects and complicates the revision. The diagnosis of aseptic loosening is based on clinical and radiological evaluation.

Diagnostic relevance of the detection of Legionella DNA in urine samples by the polymerase chain reaction.

Urine samples from 317 patients with pneumonia and from 242 patients without pneumonia were tested using a polymerase chain reaction (PCR) system for detection of the Legionella 5S rRNA gene. The results were compared with findings obtained using the established methods for diagnosis of legionellosis. Of the 317 patients with pneumonia, 58 had confirmed legionellosis, 35 had a presumptive Legionella infection, and 224 had no evidence of Legionella infection as determined by conventional methods using published criteria.

Molecular characterization of a virulence-associated epitope on the lipopolysaccharide of Legionella pneumophila serogroup 1.

For identification of lipopolysaccharide (LPS)-associated epitopes of Legionella pneumophila serogroup 1, LPS of strain Philadelphia 1 was investigated using monoclonal antibodies (MAbs). The O-specific chain of LPS is a homopolymer of 5-acetamidino-7-acetamido-8-O-acetyl-3,5,7,9-tetradeoxy-D-glycero- L-galacto- nonulosonic acid. At least four immunoaccessible epitopes were recognized by different MAbs on the intact LPS.

Monoclonal antibodies to Legionella Mip proteins recognize genus- and species-specific epitopes.

Monoclonal antibodies (MAbs) against the virulence-associated Mip protein of Legionella spp. were raised by immunizing BALB/c mice with (i) Legionella pneumophila, (ii) Legionella micdadei, and (iii) purified recombinant native Mip protein cloned from L. pneumophila Philadelphia 1.

Detection of Legionella DNA in human and guinea pig urine samples by the polymerase chain reaction.

A detection system for Legionella DNA in urine samples based on the polymerase chain reaction (PCR) was developed and tested on infected guinea pigs and patients suffering from pneumonia. Results were compared with standard methods for diagnosis of Legionnaires' disease. A primer system was selected which amplifies a 108 bp DNA fragment of the 5S rRNA gene.

Serogroup-specific and serogroup-cross-reactive epitopes of Legionella pneumophila.

A panel of monoclonal antibodies was used to serotype 343 Legionella pneumophila isolates, using the indirect immunofluorescence test and ELISA. In addition, the isolates were typed by means of absorbed rabbit antisera to provide a reference procedure. As shown by a comparison of reaction patterns, serogroup-specific monoclonal antibodies were found for serogroups 1, 2, 3, 4, 6, 7, 8, and 10.

[Detection of intracellular multiplication of Legionella pneumophila in protozoa by antigen quantification using ELISA].

Legionellae and Acanthamoeba castellanii were co-cultivated (37 degrees C, 2 days) to study the intracellular multiplication of Legionella pneumophila strains (n = 37) derived from different sources. The quantification of intracellular growth was observed by both traditional counting of colony forming units and antigen detection by ELISA using polyclonal and monoclonal antibodies. There was a good correlation between the two methods.

[RoTrac capillary pore membranes for laboratory filtration. II. Bacteria-free filtration].

Because of their special characteristics Capillary pore membranes (CPM) are now applied in several branches of separation techniques and analytics. Besides applications in particle analytics and microfiltration of different media capillary pore membranes can be used in microorganism separation. It was shown that RoTrac CPM can be used for bacteria free (or so called sterile) filtration.

[RoTrac capillary pore membranes for laboratory filtration. I. Degermination filtration].

RoTrac capillary pore membranes (CPM) are produced by means of the nuclear track technology. Thus a defined and in wide ranges independent adjunction of the different membrane parameters (diameter, density, shape and inclination of pores) is possible. The wanted uniform separation diameter of the membrane can exactly be chosen according to the size of the microorganisms to be rejected.