Design and Evaluation of the Kingston Brace

Abstract

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.