A simple measuring device for laboratory indentation tests on cartilage.

Mechanical testing of articular cartilage and repair tissue enables judgment of their capacity in withstanding mechanical loading. In the past, different methods have been developed requiring a complex technical setup and extensive data analysis. Therefore, the aim of the present project was to build up a simple measuring apparatus for laboratory indentation tests.

[The influence of bone quality and the fixation procedure on the primary stability of cementless implanted tibial plateaus].

Background: An overview of prospective studies on cementless and cemented primary knee joint endoprosthetics carried out between 1988 and 2004 reveals that the aseptic tibial loosening rate of cemented prostheses implanted with fixed meniscal bearings amounts to 2-6% within a period of 4-14 years, while cementless implanted prostheses show loosening rates of up to 28% within a period of 4-10 years. If these results arise from a lack of proper initial osseointegration as a result of insufficient primary stability, and how this is influenced by the tibial bone quality and the tibial fixation procedure has not yet been investigated.

Materials And Methods: Tibial plateaus were press-fit implanted, both screwed and unscrewed, into each of six pairs of tibial heads from corpses.

The intraindividual agreement of the bone density of the human proximal tibia.

The interindividual variability in the biomechanical properties of cadaver bones has remained an unsolved problem in biomechanical investigation procedures. For this reason, it is postulated to use matched bone pairs from the same individual for comparative biomechanical tests. The rationale behind this procedure is based on the assumption that biomechanically similar behaviour is to be expected in an intraindividual rather than an interindividual comparison.