Cartilage research typically requires a broad range of experimental characterization techniques and thus various testing setups. Here, we describe how several of those tests can be performed with a single experimental platform, i.e. a commercial shear rheometer. Although primarily designed for shear experiments, such a rheometer can be equipped with different adapters to perform indentation and creep measurements, quantify alterations in the sample thickness, and conduct friction measurements in addition to shear rheology. Beyond combining four distinct experimental methods into one setup, the modified rheometer allows for performing material characterizations over a broad range of time scales, frequencies, and normal loads.

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Acellular tissue‐engineered cartilage substitutes are promising replacement materials to mend small focal defects. The underlying therapeutic idea is to initially stabilise the defect zone and in a long‐term manner allowing for remodelling processes towards a hyaline cartilage tissue. Crucial for remodelling processes inside the implant, is the cell migration from the adjacent tissue, which will be assessed in this study.

The biodegradable WE43 magnesium alloy is an attractive biomedical material for orthopaedic implants due to its relatively high strength and corrosion resistance. Understanding the long-term corrosion behaviour in the human body plays a crucial role in the biomedical development and application of WE43 alloy for orthopaedic implants. In this work, the corrosion of an extruded WE43 magnesium alloy was investigated in a physiological environment using Dulbecco’s Modified Eagle Medium’s (DMEM) over a period of up to 10 weeks. To assess the in vitro corrosion process, we analysed the corrosion pits of the specimens’ cross sections and the composition of the corrosion layer by scanning electron microscopy. The experimental results indicated that the long-term corrosion process of WE43 magnesium alloy consists of three stages: (1) The rapid corrosion stage within the first 7 days, (2) the steady corrosion stage between 7 and 28 days, (3) the accelerated corrosion stage between 28 and 70 days. The microchemical analysis revealed a heterogeneous three-layer corrosion product with varying thicknesses of 10 to 130 µm on the surfaces of the samples for all corrosion times. It is composed of an inner layer of Mg-O, an intermediate layer of Mg-O-Ca-P, and an outer layer of Mg-O-Ca-P-C. The corrosion layers have many microcracks that allow limited contact between the liquid medium and the surface of the alloy. In addition, microgalvanic corrosion was observed to cause corrosion pits between the intermetallic rare earth element-rich phases and the Mg matrix.

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Biodegradable magnesium alloys are promising materials for orthopaedic implants. With their mechanical properties similar to native bone, magnesium alloys can overcome some significant disadvantages of conventional metallic implants. Nonetheless, the material degrades too fast for clinical approval. Therefore, the corrosion rate of the implant needs to be controlled and decelerated to guarantee sufficient mechanical support during the entire bone healing process. In this work, we analyse the corrosion behaviour of the magnesium alloy WE43 in a physiological environment and assess the influence of a plasma electrolytic coating to the corrosion process. The experimental results show that the coating significantly decreases the mass loss rate as well as the degradation of the material strength of the WE43 alloy.

In biomedical engineering it is an important challenge to predict the mechanical behaviour of living biological tissues under dynamic loading conditions. As a basis for theoretical models, experimental set-ups are necessary to trace evolutive processes, such as remodelling and growth, in biological materials. However, in order to mimic in-vivo situations most realistically, invitro bioreactor systems with physiologically enhanced loading conditions have to be developed. The present study deals with a set of bioreactor systems covering a wide range of applications for investigating remodelling behaviour of biological tissues, such as cartilage replacement materials in knee joints, tendons, and intervertebral discs.