A Method to Improve Prosthesis Leg Design Based on Pressure Analysis at the Socket-Residual Limb Interface

Abstract

This paper presents a methodology and tools to improve the design of lower limb prosthesis through the measurement of pressure analysis at the interface residual limb-socket. The steps of the methodology and the design tools are presented using a case study focused on a transfemoral (amputation above knee) male amputee. The experimental setup based on F-Socket Tekscan pressure system is described as well the results of some static loading tests. Pressure data are visualized with a colour pressure map over the 3D model of the residual limb acquired using an optical low cost scanner, based on MS Kinect. Previous methodology is useful to evaluate a physical prototype; in order to improve also conceptual design, the Finite Element (FE) Analysis has been carried and results reached so far have been compared with experimental tests. Pressure distributions are comparable, even if some discrepancies have been highlighted due to sensors placements and implemented FE model. Future developments have been identified in order to improve the accuracy of the numerical simulations.

Low-Cost 3d Devices and Laser Scanners Comparison for the Application in Orthopedic Centres

“…In medical applications, the 3D scanning of a human body involved mainly highly rated laser scanners for acquiring the parts of interest, in order to improve diagnosis or to facilitate the creation of 3D printed orthosis or prosthesis (Baronio et al, 2016;Telfer, Woodburn, 2010). This device was used as a tracking system (Wang et al, 2012), for rehabilitation (Lange et al, 2011), for foot orthoses (Dombroski et al, 2014) and for improving the design of leg prosthesis (Colombo et al, 2016) with the aim to find a proper way to acquire 3D data using low cost sensors. On the other hand, recently the Structure Sensor was developed for acquiring 3D data of the environment simply connecting it to an iPhone or an iPad.…”

“…For example, if we have to develop a new wrist orthosis, the shape could be still similar to the real one but the error would not be acceptable because of the thin skin layer around the bones. On the other hand, the Kinect 1 would still be a valid device for creating a socket for the prosthesis of an above knee amputee, as the case described in (Colombo et al, 2016), because of the thicker layers of soft tissues around the bone that could mitigate the deviation. Even though the Kinect 2 showed good performance on the flat plane, the poor alignment determined the inability in a realistic acquisition of patients for O&P purposes.…”

Comparison of geometrical accuracy of active devices for 3D orthopaedic reconstructions

“…The Kinect sensors, both version 1 and 2, were used for several 3D applications in cultural heritage [12], for robotics [13] and for human body scanning [14]. These devices were used for tracking surgery tools [15], for rehabilitation [16] and for improving the design of foot orthoses and leg prosthesis [17,18].…”

Combining Freehand Ultrasound-Based Indentation and Inverse Finite Element Modeling for the Identification of Hyperelastic Material Properties of Thigh Soft Tissues

“…This is the reason why a particular attention has been paid to the mechanical behaviour of soft tissues under contact loadings in the last decade [1][2][3]. One way to evaluate loadings at the interface is to design subject specific Finite Element (FE) models [2,[4][5][6]. Several barriers exist to the clinical use of these models.…”