Due to the increasing life expectancy the incidence of gonarthrosis, the degeneration of articular cartilage and bone in the knee joint, is increasing worldwide. Although the success rate of knee arthroplasties is high, complications like the loosening of the implant necessitate subsequent treatments. Moreover, the morphology and microstructure of the knee joint varies considerably between patients, therefore the anatomical expertise of orthopedic surgeons is essential. In this analysis we therefore investigate the variation and micro-architectural alterations in subchondral bone in osteoarthritis (OA) patients undergoing a knee replacement surgery. We investigate OA bone degenerations using clinical X-rays and micro-computed tomography (micro-CT). Tibial bone samples are collected from 100 patients undergoing a total knee arthroplasty at the Klinikum Wels-Grieskirchen. Images are obtained using an industrial micro-CT scanner RayScan 250E. Microstructural parameters include bone volume fraction and cortical thickness of the subcondral bone and are obtained from micro-CT images with isometric voxel sizes of 50 µm. Using micro-CT, we show a high morphological variation in relation to cortical thickness, both within the respective condyle as well as between the medial and lateral condyle. Cortical thickness seems to correlate with cartilage thickness and knee joint alignment. The results are incorporated into a gonarthrosis database that integrates microstructural parameters via a combined analysis of X-ray and micro-CT data. This database aims to facilitate the assessment of osteoarthritis, i.e. in relation to cartilage degeneration, in future patients on the basis of the investigated patient collective.
Innovative developments for total knee arthroplasty enhanced anatomical design and fixation in order to decrease particle-induced aseptic implant loosening. As hypersensitivity reactions to metallic implant materials have been recognized to possibly cause premature implant failure, ceramic materials might constitute a proper alternative solution. The aim of this prospective short-term study was the initial comparison of a completely metal-free ceramic with a geometrically identical metallic arthroplasty over a one-year follow-up period. Eighty patients requiring primary total knee arthroplasty were enrolled within this open-label prospective comparative study. Patients were randomly divided among two groups to either undergo implantation of a completely metal-free system using a composite matrix material containing aluminum oxide (Al2O3) and zirconium oxide (ZrO2) (n=40), or an anatomically identical metallic knee system made of a cobalt-chromium alloy (Co28Cr6Mo) (n=40) produced by the same manufacturer. Clinical assessment was performed preoperatively, and during follow-up at three and twelve months using the Knee Society Score, Oxford Knee Score and EQ-5D-VAS. For radiological evaluation, standard preoperative and postoperative standardized radiographs were taken at mentioned follow-up visits.Background
Methods
Today TKR is considered one of the most successful operative procedures in orthopedic surgery. Nevertheless, failure rates of 2 – 10% depending on the length of the study and the design are still reported. This provides evidence for further development in knee arthroplasty. Particularly the oxide ceramics used now in THA show major advantages due to their excellent tribological properties, their significantly reduced third-body wear as well as their high corrosion resistance. A further advantage of ceramic materials is their potential use in patients with metal allergy. Metallic wear induces immunological reactions resulting in hypersensitivity, pain, osteolysis and implant loosening. The purpose of our study was to examine the safety of the tibial component of a novel all-ceramic TKR. We tested the tibial components of the primary knee implant BPK-S Integration Ceramic. Both the tibial and the femoral component consist of BIOLOX®delta ceramic The standards ISO 14879-1 and ASTM F1800-07 describe the test set-up for the experimental fatigue strength testing of tibial components from knee implants. We conducted the testing with a significantly increased maximum load of 5,300 N (900 N are required). A final burst strength test was carried out after the fatigue load testing in the same embedding and with the same test set-up.Introduction
Materials and Methods
Treatment of non-union is a highly demanding field with respect to bone healing. BMP 7 is a useful, wide-ranged tool in treating non-union of the foot and benign bone tumors. It represents a low-risk procedure with a high level of reliability. Treatment of non-union is a highly demanding field with respect to bone healing. Treatment of tibial fracture non-union with the bone morphogenetic protein 7 (BMP-7) has been successfully reported. BMP 7 is a recombinant human protein produced in ovary cells of the Chinese hamster. It is responsible for the differentiation of mesenchymal stem cells from the periost, muscle and sponious bone and stimulates bone formation. It is the aim of our study to investigate the use of BMP 7 for other locations than the tibia, such as the foot and benign bone tumors. We strive for union or revision in each medical case.Summary Statement
Introduction
RANK is expressed in 18% of human osteosarcomas and is likely to provide additional prognostic information for clinical purposes in osteosarcoma patients at the time of diagnosis. The receptor activator of nuclear factor kappa (RANK), a member of the tumor necrosis factor family, is activated by its ligand and regulates the differentiation of osteoclasts and dendritic cells. Local growth of osteosarcoma involves destruction of the host bone by osteoclasts and proteolytic mechanisms. Although prognosis of osteosarcoma has been improved by chemotherapy during the last decades, the problem of non responders and the lack of prognostic markers remains. It is the aim of this study to investigate the prognostic and predictive value of RANK expression in human osteosarcoma.Summary Statement
Introduction
