Nanoindentation and atomic force microscopy surface characterisation of human femoral head articular cartilage

• Main Author: Austin, Megan
• Published: University of Strathclyde 2013
• Subjects: 610.28
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.605942

Articular cartilage (AC) is a remarkable tissue in which a complex composition and hierarchical structure provides an optimized function in load support and joint lubrication. Osteoarthritis (OA) is the degeneration and consequent loss of AC. OA is increasingly becoming more of a problem; an increase in OA leads to a greater number of replacement surgeries creating a financial burden on the population. The mechanical etiology and function of OA is not fully understood. Nanoindentation and AFM techniques were investigated to measure the nanomechanical properties of AC. Instrumental nanoindentation was employed to characterize the variation of the mechanical properties of OA across the human femoral head and to understand the OA degenerative process further. Qualitative analysis allowed the visualization and comparison of OA over the femoral head. This demonstrated that the worst affected area of OA was the superior posterior area which corresponds to the area of stiffest cartilage found on healthy cadaveric femoral heads. The qualitative results showed that OA potentially initiates at this location. A potential biomechanical biomarker of OA has been found medially around the fovea capitis ligament. We hypothesize that when the cartilage surface attaches to a nanoindeter tip this indicates signs of a pannus-like tissue, suggestive of early OA. This is crucial for the development of new early osteoarthritis diagnostic tools. Extensive further work is necessary in the development of more effective diagnostic devices.