Spinal fusion surgery relies on surgical implants such as pedicle screws for fusion of bone around the affected areas of the spine. Failure modes on these surgeries include high rates of the surgical implants loosening and in other cases hardware breakage. Existing studies for these failures demonstrate that the pullout strength of these pedicle screws is influenced by various factors such as the design of the implants, the screw trajectory and bone quality but also the experience level and technique of the surgeon.;The objective of this study was to characterize these surgeon profiles using metrics based on their interaction with the pedicle screws. During the pedicle screw insertion, wobble, generated by the surgeon, alters the path for proper placement leading to failure rates post implantation. Using foam blocks that match various levels of bone quality ranging from young healthy bone to that which mimics osteoporotic bone, pedicle screws are inserted by health care professionals in surgical simulations. During these insertions, surgical profiles are generated in the form of screw insertion angle and maximum handle diameter, and then correlation to the pullout strength of these pedicle screws is sought.;In all cases with lower bone density, the average pullout strength differed when surgeon techniques of health care professionals were compared to a novice with little to no experience in pedicle screw placement. Amongst the surgeons, the pullout forces were within 95% Confidence Interval of expected values and as such the maximum handle diameter during the insertion did not provide a correlation. The screw insertion angle did however correlate with pullout strength data, only in the lower density bone.;The thesis explores the various challenges to this pedicle screw insertion tracking and provides suggestions for further tracking post data analysis.
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