Lisfranc injuries affect at least 1 out of every 55,000 people each year. Although they are rare foot injuries, their effects can be devastating. 20-40% of Lisfranc injuries are missed upon first presentation. This increases the number of poor outcomes, resulting in a disproportionate number of malpractice lawsuits and compensation claims. The Kingston Brace was designed to support an injured foot during a CT scan with the goal of providing the diagnosing physician with the best diagnostic information possible. A prototype was designed and built to support a variety of foot orientations in order to determine which orientation is optimal for Lisfranc joint CT scanning. Three fresh frozen cadaver feet were put through several experiments with the Brace. The 2D diagnostic quality of CT scans taken using the Kingston Brace was compared against that of CT scans using the existing protocol. The Kingston Brace allows for a greater visualization of the injured Lisfranc joint than the existing CT protocol. Lisfranc joint spreading was used as a measure of potential pain in injured patients. The joint spreading was minimal, suggesting that injured patients would not feel as much additional pain during imaging. Also, the adoption of the Kingston Brace resulted in no change in the morphological parameters resulting from more advanced 3D analysis. The experimentally determined optimal Kingston Brace orientation was found to be 9◦ of plantarflexion and 13◦ of eversion. These orientations can be incorporated into the next generation of Kingston Brace design. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2009-07-06 15:01:57.866

No description available.

Foot posture is an important characteristic that can affect kinematics, plantar loading, and injury risk. Arch height is one common aspect of foot posture, and it is estimated that about 60% of the population has normal arches while 40% of the population is either pes planus or pes cavus. It is important to be able to accurately and reliably assess foot posture characteristics in order to propose interventions that could prevent injuries due to abnormal foot alignment. However, despite multiple classification metrics, many of the devices that are commonly used for foot posture measurements are not economically feasible for smaller clinics or research labs. Therefore, the first purpose of this study was to develop an affordable device to measure different foot posture characteristics. The Foot Posture Measurement System was developed and can measure total foot length, truncated foot length, foot width, dorsum height, and navicular height. This system was shown to have good to excellent validity (ICC = 0.908-0.994) and repeatability (ICC = 0.867-0.996) when compared to a 3D scanner. This device was then used in the second portion of this study, which evaluated the effects of ankle braces on plantar loading patterns in individuals with different foot postures. Contact area, peak force, force-time integral, and center of pressure were evaluated during a walk, run, and cut while the participant was unbraced, wearing a lace-up stabilizer brace, and wearing a semi-rigid brace. It was demonstrated that arch height did affect the maximum plantar forces during all tasks (p=0.001-0.047), as hypothesized based on previous studies. Additionally, this study found that ankle braces affected contact area (p=0.001-0.0014), maximum force (p<0.001 – p=0.043), and force-time integral (p<0.001 – p=0.015) during the walk, run, and cut. This is a novel finding and points to the potential for an impact of ankle braces on plantar loading during athletic activities, independent of foot type. / Master of Science / Foot posture is an important characteristic that can affect daily life and contribute to the risk of injury. Arch height is one common aspect of foot posture, and it is estimated that about 60% of the population has normal arches while 40% of the population is either high arched or low arched/flat footed. It is important to be able to accurately and reliably assess foot posture characteristics in order to propose interventions that could prevent injuries due to abnormal foot alignment. However, despite multiple classification metrics, many of the devices that are commonly used for foot posture measurements are not economically feasible for smaller clinics or research labs. Therefore, the first purpose of this study was to develop an affordable device to measure different foot posture characteristics. The Foot Posture Measurement System was developed and can measure five different length, width, and height characteristics of the foot. This system was shown to be valid when compared to a 3D scanner and repeatable between days. This device was then used in the second portion of this study, which evaluated the effects of ankle braces on individuals with different foot postures. Four different force and pressure variables were examined within the foot during a walk, run, and cut while the participant was unbraced, wearing a lace-up stabilizer brace, and wearing a semi-rigid brace. It was shown that arch height did alter plantar loading measures during all tasks, as hypothesized based on previous studies. Additionally, this study found that ankle braces affected all variables during the walk, run, and cut. This is a novel finding and points to the potential for an impact of ankle braces on plantar loading during athletic activities, independent of foot type.