Regional biomechanical properties of the articular surface, in the human distal femur, in health and disease

Osteoarthritis is the leading cause of disability among North American adults. This thesis investigates the design of a digital atlas capable of displaying elastic material properties and thickness mapped across the human distal femur. MicroCT scans and a double indentation stress-relaxation method were used to create the digital maps on steriolithographic images of femurs. Cartilage thickness, Poissons ratio and shear modulus were obtained from seven normal and six osteoarthritic knees. Significant sub-regional differences in the thickness and elastic properties of cartilage were identified over the trochlea, medial and lateral condyles. Consistent patterns are present in both healthy knees and osteoarthritic knees, although there were significant differences in the osteoarthritic group. Overall, a method was developed to non-destructively obtain thickness and elastic properties of the cartilage surface. Digital maps created using this technology can augment the capabilities of current image guided surgery systems during mosaic arthroplasty.