Amputee locomotion: Lower extremity loading using running-specific prostheses

Abstract

Carbon fiber running-specific prostheses (RSPs) have allowed individuals with lower extremity amputation (ILEA) to actively participate in sporting activities including competitive sports. In spite of this positive trait, the RSPs have not been thoroughly evaluated regarding potential injury risks due to abnormal loading during running. Vertical impact peak (VIP) and average loading rate (VALR) of the vertical ground reaction force (vGRF) have been associated with running injuries in able-bodied runners but not for ILEA. The purpose of this study was to investigate vGRF loading in ILEA runners using RSPs across a range of running speeds. Eight ILEA with unilateral transtibial amputations and eight control subjects performed overground running at three speeds (2.5, 3.0, and 3.5 m/s). From vGRF, we determined VIP and VALR, which was defined as the change in force divided by the time of the interval between 20 and 80% of the VIP.We observed that VIP and VALR increased in both ILEA and control limbs with an increase in running speed. Further, the VIP and VALR in ILEA intact limbs were significantly greater than ILEA prosthetic limbs and control subject limbs for this range of running speeds. These results suggest that 1) loading variables increase with running speed not only in able-bodied runners, but also in ILEA using RSPs, and 2) the intact limb in ILEA may be exposed to a greater risk of running related injury than the prosthetic limb or able-bodied limbs.

Dynamic elastic response prostheses alter approach angles and ground reaction forces but not leg stiffness during a start-stop task

“…This is likely to prevent injury of the residual limb (Dudek et al, 2005;Milner et al, 2005). The high impact peaks and tendency towards higher loading rates of the IL agrees with past research on running (Hobara et al, 2014) and…”

Running at submaximal speeds, the role of the intact and prosthetic limbs for trans-tibial amputees

“…The inability on the PL to increase vertical and propulsive forces will result both in reduced accelerations and shorter aerial times. This supports the mechanism that higher speeds will result from increased SF rather than SL, consistent with past research on amputee treadmill and over-ground running [5,6,10].…”

“…SL increases are the primary mechanism to run at faster sub-maximal steady-state speeds (between 3.5-7m/s) and the ankle plantarflexors play a primary role [8] with faster sprinting speeds achieved though increasing ground reaction forces [9] including their rate of development and decline. It is unclear how amputees alter SL, SF and ground reaction impulse to run at different sub-maximal speeds without a functioning ankle joint, as research is limited to imposed controlled speeds using different designs of RSP [6,10,11]. Potentially, a spontaneously self-selected running speed may be selected to optimise the mechanics of any prosthesis.…”

Effects of applied stress ratio on the fatigue behavior of additively manufactured porous biomaterials under compressive loading

“…However, porous biomaterials used in load-bearing orthopaedic applications are often subjected to various types of daily activities such as walking, hopping, and running. These activities are associated with different types of loading profiles [25][26][27] that might be different in their magnitude, frequency bands, and other characteristics.…”