Validation of a portable shoe tread scanner to predict slip risk

Abstract

Problem: Worn shoes are an important contributor to occupational slip and fall injuries. Tools to assess worn tread are emerging; imaging tools offer the potential to assist. The aim of this study was to develop a shoe tread scanner and evaluate its effectiveness to predict slip risk. Methods: This study analyzed data from two previous studies in which worn or new slip-resistant shoes were donned during an unexpected slip condition. The shoe tread for each shoe was scanned using a portable scanner that utilized frustrated total internal reflection (FTIR) technology. The shoe tread parameters of the worn region size (WRS) for worn shoes and total contact area for new shoes were measured. These parameters were then used to predict slip risk from the unexpected slip conditions. Results: The WRS was able to accurately predict slip risk, but the contact area was not. Discussion: These findings support that increased WRS on the shoe outsole is associated with worse slip outcomes. Furthermore, the tool was able to offer robust feedback across a wide range of tread designs, but the results of this study show that the tool may be more applicable for slip-resistant shoes that are worn compared to their new counterparts. Summary: This study shows that FTIR technology utilized in this tool may be a useful and portable method for determining slip risk for worn shoes. Practical Applications: This tool has the potential to be an efficient, objective, end-user tool that improves timely replacement of shoes and prevention of injuries.