Socket reaction moments in transtibial prostheses during walking at clinically perceived optimal alignment

Background and Aim: The socket reaction moments are directly measured at the base of a socket and may be useful for fitting a prosthesis. Previous studies have focused on the effect of prosthetic alignment changes on them. The aim of this study was to explore their range at clinically perceived optimal alignment by investigating the individual differences. Technique: In total, 11 amputees using unilateral transtibial prostheses with solid-ankle-cushion-heel (SACH) feet were recruited. The socket reaction moments were measured using a custom instrumented prosthesis alignment component and plotted. Eight variables that were related to their magnitude (Nm/kg) and timing (% stance of event) as well as cadence (steps/minute) were calculated for each amputee. Their mean, standard deviation, maximum value, minimum value, and range were subsequently analyzed. Discussion: This study may serve as a foundation to explore the range of individual differences in socket reaction moments in transtibial prostheses. Clinical relevance Socket reaction moments can be conveniently measured in the clinical setting. Prosthetists could potentially use them as one of the criteria to align prosthesis in addition to observational gait analysis and amputees perception.