Status Report 1 Patrick Melton Daniel Escobar

Recap - Objective The objective is to utilize the research of the medical literature gathered and translate the findings to design a device that will position the ankle for improved visualization of the subtalar joint and allow for enhanced stability analysis.

Recap – Radiographic Views Cobey view Hindfoot Alignment view Long axial view Stress Broden view

Update – Stress Broden View Two articles concluded that the Stress Broden view is not ideal for subtalar joint analysis. Compared subtalar tilt in unstable and normal ankles using Stress Broden view vs. CT scan – measurements were not statistically significant. Stress Broden view recorded high degree of subtalar tilt in both normal ankles and unstable ankles – accurate measurements could not be obtained.

Roadblocks How does the subtalar joint act under different areas of stress application? What is the best way to open the subtalar joint by applying stress to the ankle for an ideal radiographic view?

Possible Solution Obtain kinematic model of the hindfoot so that we can simulate the application of stress on the subtalar joint. Forefoot is not included, so it will be difficult to accurately simulate our device using the kinematic model.

Possible Solution Article used a combination of supination and dorsiflexion. Ishii, T., S. Miyagawa, et al. (1996). "SUBTALAR STRESS RADIOGRAPHY USING FORCED DORSIFLEXION AND SUPINATION." J Bone Joint Surg Br 78-B(1):

Update - Design Should have different size heel cups, or a single adjustable heel cup. Three layers: Base plate, full foot plate, forefoot plate. Base plate: foundation for adjustable locking mechanism and heelcup. Full foot plate: allows for angular adjustment of entire foot, enabling supination. Forefoot plate: will allow for additional adjustment of forefoot, enabling dorsiflexion.

Device Preliminary Model

Update – Gantt Chart