Insoles created to reduce foot pressure for diabetics

UN/DICYT Currently the project is being tested in five patients to whom they previously measured their sole pressures and performed conventional walking studies in order to develop insole topography. Researchers also carried out a clinical follow-up to observe their evolution. 

The basic issue is related to the pain in the feet of these patients, which can ultimately cause tissue damage; therefore the UNal Biomechanics Research Group developed surfaces using an algorithm from feet sole measurements. 

This interdisciplinary research project was carried out with support from Faculty of Medicine’s Rehabilitation Department Professor Octavio Silva, and Biomedical Engineering masters candidate Oscar Rodríguez. 

Rodríguez says that in the clinical process, treatment is carried out depending on the experience and expertise of the specialist. The model helps to quantitatively show the interfase between the feet and the support surface, whether it is an insole, shoe or surface on which they walk. 

“We register what happens with the types of loads feet are subject to in a highly dynamic walking process, which changes constantly from the moment of impact to the time when the feet leave the floor,” said Rodríguez. 

With this information they calculate an average and determine the most vulnerable or impacted areas in order to offer a tangible surface and not replace the clinical process but to support the specialist with more accurate criteria. 

According to the expert, the threshold between normal and abnormal pressures is 11 kilos per square centimeter; a greater pressure means damage to the tissue of the patient’s feet. In this sense this could produce lacerations and tears which increase the risk of having to amputate. 

Department of Mechanical Engineering and Mechatronics Professor and Research Group Coordinator Carlos Julio Cortés Rodríguez says the process is based on measuring the insole pressure points with sensors. 

The following step was to produce the insole surface using a computer assisted 3D polymer printing process, although they can also use a numeric control machine which removes the material in a controlled manner. 

“The idea behind this is for the procedure to be standard for many diabetic patients and others with feet pathologies,” said Cortés.