Several investigators have pointed out that electron and neutron contamination from high-energy photon beams are clinically important. The aim of this study is to assess electron and neutron contamination production by various prostheses in a high-energy photon beam of a medical linac. A 15 MV Siemens PRIMUS linac was simulated by MCNPX Monte Carlo (MC) code and the results of percentage depth ...

More than twenty years ago, hydroxyapatite (HA), calcium phosphate ceramics, was introduced as a coating for cementless hip prostheses. The choice of this ceramic is due to its composition being similar to organic apatite bone crystals. This ceramic is biocompatible, bioactive, and osteoconductive. These qualities facilitate the primary stability and osseointegration of implants. Our surgical e...

Nine uncemented hip prostheses of modular design were revised because of late infection (2 cases), femoral stem loosening or fracture (2), loosening of threaded cups (3) and protrusion of bipolar cups (2). At surgery we found tissue discoloration and macroscopic corrosion in four of the nine prostheses, located at the head-neck junction. Histological examination in most cases showed extensive n...

In this study, porous-coated, fixed with screwed-system femoral prosthesis and total hip prosthesis composed of screwed-system acetabular cup were applied on 21 dogs of different breeds, sexes and ages. Total hip arthroplasty (THA) was applied as one sided in all cases. In 7 cases luxation occured and in 5 of them the prostheses were taken out. One of the cases had a second operation for disloc...

.........................................................................................7 Introduction....................................................................................9 Femoral revision and allograft impaction ....................................9 Total hip replacement in young patients ...................................10 Hydroxyapatite coating of femoral stems...............

High energy radiotherapy can produce contaminant neutrons through the photonuclear effect. Patients receiving external beam radiation therapy to the pelvis may have high-density hip prostheses. Metallic materials such as those in hip prostheses, often have high cross-sections for neutron interaction. In this study, Thackray (UK) prosthetic hips have been irradiated by 18 MV radiotherapy beams t...

12. Howie DW, Middleton RG, Costi K. Loosening of matt and polished cemented femoral stems. J Bone Joint Surg [Br] 1998;80-B:573-6. 13. Kärrholm J, Borssèn B, Löwnhielm G, Snorrason F. Does early micromotion of femoral stem prostheses matter?: 4-7 year stereoradiographic follow-up of 84 cemented hip prostheses. J Bone Joint Surg [Br] 1994;76-B:912-7. 14. Walker PS, Mai SF, Cobb AG, Bentley G, H...

OBJECTIVES An ongoing prospective study to investigate failing metal-on-metal hip prostheses was commenced at our centre in 2008. We report on the results of the analysis of the first consecutive 126 failed mated total hip prostheses from a single manufacturer. METHODS Analysis was carried out using highly accurate coordinate measuring to calculate volumetric and linear rates of the articular...

A large number of short stem prostheses for hip -arthroplasty have been introduced in the past years. Although there is a large increase of publications about short stems, there is still little data available about survival and revision rates. We report prospectively on the outcome of 84 consecutive NANOS® short stem prostheses in 81 patients. We have included 37 female patients and 44 male pat...

BACKGROUND To determine the effect of different imaging options and the most efficient imaging strategy for treatment planning of patients with hip prostheses. METHODS The planning kilovoltage CT (kVCT) and daily megavoltage CT (MVCT) studies for three prostate cancer patients with bilateral hip prostheses were used for creating hybrid kVCT/MVCT image sets. Treatment plans were created for kV...