Microsection analysis of cortical form-fit of a custom femoral component in total hip arthroplasty: an in vitro study.

Custom femoral components have been developed for total hip arthroplasty to maximize cortical form-fit and thereby to reduce the problems of stress shielding and aseptic loosening. Limited information is available about how much endosteal cortical contact can actually be achieved with these expensive implants. The aim of this study was therefore to verify the exact cortical contact of a custom made stem using microsections and comparing it to a standard stem with similar design.

Immediate changes of bone density caused by the implantation of a femoral stem--a DEXA study. Ulf.Leichtle@med.uni-tuebingen.de.

Considerable immediate periprosthetic bone density changes after implantation of femoral stems have been observed comparing DEXA measurements taken pre- and post-operatively. This is important in relation to the interpretation of DEXA studies. We analysed these density changes under standardised experimental conditions.

Changes of periprosthetic bone density after implantation of an anatomical femoral stem with cemented and cementless fixation.

This prospective 12 months dual energy x-ray absorptiometry study evaluated differences in periprosthetic bone mineral density (BMD) in 25 patients undergoing cementless and in 18 patients undergoing cemented unilateral total hip arthroplasty (THA) using the Optan stem, which has the same geometric design for both fixation options. The clinical outcome scores after one year were excellent in both groups. Periprosthetic BMD measurement demonstrated bone loss medially and laterally in the proximal femoral regions following cementless fixation, whereas cemented fixation resulted in predominantly lateral bone resorption.

Three-dimensional measurements of the pressure distribution in artificial joints with a capacitive sensor array.

A spherically folded capacitive pressure sensor array is introduced and characterized. By placing the sensor array between the ball and the cavity of artificial joints, the pressure distribution within the joint was recorded with spatial resolution for different size matching between the ball and the cavity, for different directions of loading and for joints with incomplete cavities. The performance of the sensor array is analyzed, possible fields of application as well as its limitations are discussed.

Enhanced biocompatibility for SAOS-2 osteosarcoma cells by surface coating with hydrophobic epoxy resins.

Background And Aims: Implants for surgical needs are produced from different materials including metals, alloys, ceramics or polymers. Metal implants are preferred in those disciplines where sufficient mechanical strength is needed, including traumatology, orthopedic or dental surgery. Further, modern tissue engineering techniques require scaffold materials to generate shape and stability for in vitro generated transplants.