The potential use of fiber-reinforced based polycarbonate-urethanes (PCUs) as candidate meniscal substitutes was investigated in this study. Mechanical test pieces were designed and fabricated using a compression molding technique. Ultra-High Molecular Weight Polyethylene (UHMWPE) fibers were impregnated into PCU matrices, and their mechanical and microstructural properties evaluated. In particular, the tensile moduli of the PCUs were found unsuitable, since they were comparatively lower than that of the meniscus, and may not be able to replicate the inherent role of the meniscus effectively. However, the inclusion of fibers produced a substantial increment in the tensile modulus, to a value within a close range measured for meniscus tissues. Increments of up to 227% were calculated with a PCU fiber reinforcement composite. The embedded fibers in the PCU composites enhanced the fracture mechanisms by preventing the brittle failure and plastic deformation exhibited in fractured PCUs. The behavior of the composites in compression varied with respect to the PCU matrix materials. The mechanical characteristics demonstrated by the developed PCU composites suggest that fiber reinforcements have a considerable potential to duplicate the distinct and multifaceted biomechanical roles of the meniscus.

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Purpose: The knowledge of the normal geometrical characteristics of the proximal humerus is crucial to the success of its arthroplasty. This important information, is however, limited for the South African population. Therefore, this study investigates the three-dimensional morphometric parameters, specifically examining the intra-ancestral differences within the South African population. Methods: With the aid of geometry extraction techniques, various morphometric characteristics were measured on South African cadaveric humeri originating from three ethnicities including whites, blacks, and mixed in the ratio 1:2:4. Results: There is a significant mean difference in humeral head diameter between blacks and whites and between mixed and whites with a mean difference of [Formula: see text]4.86, 95% CI ([Formula: see text], [Formula: see text]) and [Formula: see text], 95% CI ([Formula: see text], [Formula: see text]), respectively. Similarly, for articular surface diameter, a significant mean difference of [Formula: see text], 95% CI ([Formula: see text], [Formula: see text]) and [Formula: see text], 95% CI ([Formula: see text], [Formula: see text]) were recorded between blacks and whites and between mixed and whites, respectively. Conclusion: The outcome of our study showed that the shape of the South African proximal humerus varies distinctively within the different ethnicities that were measured. The findings from this study may provide the data required to design and develop a new shoulder implant appropriate for South African patients.

Musculoskeletal replacement parts are increasingly evolving globally. However, the high cost associated with these parts calls for innovative yet affordable candidate materials. Therefore, this study involves the local production of hydroxyapatite from bovine bone wastes using an unconventional drying technique and its characterization as an alternative material for bone substitutes. The bovine bones used are safe from prions or infectious diseases such as bovine spongiform encephalopathy (BSE) and were further processed using calcination means that excludes possible existing disease. The results obtained from various analyses of the calcined powder confirmed the formation of HAp phase in substantial amount. The preparation was found to be economically viable and production route was time‐ and cost‐ effective.

Medical grade silicone reinforced with nylon was fabricated into composites using compression moulding. Samples of both fibre and non-fibre reinforced silicones were mechanically evaluated. The composite with the optimum properties has its tensile modulus increased significantly from 10.7 ± 2.9 MPa to 114.6 ± 20.9 MPa when reinforced with 5% v/v nylon fibres. This value is within the circumferential tensile modulus of the native meniscus. Unlike the tensile modulus, the compressive modulus of the composite was found to reduce from 2.5 ± 0.6 MPa to 0.7 ± 0.3 MPa when fibres were incorporated; which is closer to the aggregate compressive modulus of the native meniscus. The meniscus, a complex and frequently damaged tissue, requires a substitute capable of reproducing similar biomechanical functions, and the developed composite material with comparable mechanical characteristics could serve as a useful step in the goal of producing meniscal replacement that gives satisfactory long term outcomes.