Grant: Master's Award: Canada Graduate Scholarships

Accurate assessment of the structural stability of the callus formed during post-fracture healing is crucial in directing clinical treatment. This is important with respect to required follow up and return to function under conditions of normal bone healing and determining the need for additional interventions when healing does not proceed normally. We propose to develop a robust non-invasive characterization method to quantify fracture status that accurately describes the mechanical strength of the healing bone. Previous investigators studying fracture healing have found only weak correlations between measurements from image analysis and biomechanical integrity of healing fractures. We hypothesize that the measurement of 3D connectivity at the fracture site will correlate strongly with biomechanical strength, allowing this measure to predict the strength of healing bone. Fracture healing will be assessed through a preclinical study in mice. Two common types of femoral fractures will be created and allowed to heal for 14 or 21 days after surgical fixation. Micro-Computed Tomography (uCT) images will then be acquired of each fracture site. A highly automated algorithm will be developed to filter the images, segment the healing fracture sites, and quantify the 3D connectivity of cortical bone at the fracture site. Torsional mechanical testing will then be completed on each of the 40 excised femora. Pearson's correlation analysis will be used to determine the ability of the newly developed 3D connectivity measure to predict the strength of the healing femora. Currently, care of fracture patients is mainly dependent on time from the initiation of treatment, plain radiographs, and serial clinical assessments. These are time consuming and surgeon experience dependent. Advances in high-resolution peripheral microCT technology (XtremeCT) would allow future clinical translation of 3D connectivity-based image analysis for quantitiative assessment of fracture healing.