Design and evaluation of a novel fixture to optimally support a Lisfranc injured foot during CT scanning

Lisfranc injuries affect at least 1 out of every 55,000 people each year. Although they are relatively uncommon foot injuries, their effects can be severe: 20–40% of Lisfranc injuries are missed upon first presentation. This increases the likelihood of poor outcomes, especially if associated with a workplace injury. These injuries result in a disproportionate number of malpractice lawsuits and compensation claims. The Kingston Brace was designed to support an injured foot during a computed tomography (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. It was used 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 taken using the existing protocol. The Kingston Brace allows for a better 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 in the Kingston Brace was minimal, suggesting that additional pain felt by injured patients during imaging would also be minimal. The adoption of the Kingston Brace resulted in no change in the morphological parameters resulting from more advanced 3D analysis. The best experimentally determined Kingston Brace orientation was found to be 10° of plantarflexion and 11° of eversion.