Pressure Distribution Management System in 3D Printed Transtibial Prosthetic Socket during Static Loading: A Preliminary Assessment during Stance Phase

Abstract

Background A management system within a prosthetic socket for efficient redistribution and interface pressure reduction is highly demanded. This research article developed a new control system for interface pressure in a 3D printed transtibial prosthetic socket. This system aimed to redistribute and reduce the high interface pressure along residual limb regions in a 3D printed socket. Methods A 3D printed socket was built with tiny air bladders that were integrated with the liner. This 3D socket had three air bladders located on the posterior, lateral, and medial sides, and connected to three separate mini pumps and valves for inflation and deflation. The air bladders' inflation and deflation were controlled by using a pre-programed keypad. The keypad with an electronic system (electronic circuit, mini pumps, and valves) was attached to a prosthetic pylon in a small box. A universal tensile machine was employed to apply loads into the prosthetic device to resemble human body weight. The interface pressure in the 3D printed socket was evaluated by using F- socket transducers at proximal, middle, and distal regions of an artificial residual limb during inflation and deflation of the air bladders in stance phase. Results The pressure control system minimized the interface pressures within the 3D printed prosthetic socket during inflation. The posterior and medial sides recorded a maximum reduction in pressure during the inflation of posterior and medial air bladders, respectively. Statistically, the highest significant pressure reduction (p < 0.05) was 6.81%, which was recorded at the posterior proximal subregion and 3.44% (p > 0.05) at the medial middle, but it was not significant. There was no statistical change in the mean pressure values at the whole anterior side, but there were significant differences during lateral and medial air bladder inflation and deflation. Conclusions This study is intended to recognize the impact of high interface pressure around the residual limb more deeply. The new pressure distribution management system offered rearrangement with minimized interface pressure over the artificial residual limb subregions.