Biomedical Engineering ETDs

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The purpose of this study was to evaluate the use of one-third tubular plates for the treatment of benign defects in the medial distal metaphysis of the femur. Benign cysts are a common occurrence in long bones, and are of concern in load-bearing bones, such as the tibia and femur. These space-occupying growths are removed by curettage of the affected region. Numerous post-curettage management options have been described in the literature, which generally include filling the defect with either synthetic or biological materials. Unfortunately, complications, such as infectious disease transmission, thermal injury, and a robust inflammatory have all been reported in the literature. In response to these concerns, a number of studies reported successful healing of benign cortical defects in long bones with no augmentation after curettage, however, the lack of structural support results in an increased risk of fracture through the defect site. Therefore, it is advantageous to investigate a treatment option that adds structural support to the defect site and permits the use of osteoconductive and osteoinductive materials within the bone cavity. The purpose of this thesis was threefold: First, a quasi-static experimental comparison of intact and cortical defect specimens was conducted to determine the structural consequences incurred by the introduction of a 15 mm cortical defect under isolated axial and torsional loads. Second, an experimental combined axial/torsional fatigue analysis was employed to further analyze the behavior of the defect specimens, and to determine the structural stiffness regained by the addition of a one-third tubular plate. Third, a numerical approach was used to consider the structural consequences of varying sized defects under isolated and combined quasi-static axial and torsional loading, and to further analyze the results of adding the plate to the defect specimens. This study revealed that a one-third tubular plate might be a clinically viable option for structural support of small cortical defects in the distal femur. Furthermore, the loss in stiffness by the defect is exacerbated under combined axial/torsional loading. This is a more physiologically relevant loading mode and may provide more clinically useful results.




biomechanics, femur, benign, tumor, orthopaedics

Document Type


Degree Name

Biomedical Engineering

Level of Degree


Department Name

Biomedical Engineering