Continuous relative phases of walking with an articulated passive ankle–foot prosthesis in individuals with a unilateral transfemoral and transtibial amputation: an explorative case–control study

Abstract

Background A mechanical ankle–foot prosthesis (Talaris Demonstrator) was developed to improve prosthetic gait in people with a lower-limb amputation. This study aims to evaluate the Talaris Demonstrator (TD) during level walking by mapping coordination patterns based on the sagittal continuous relative phase (CRP). Methods Individuals with a unilateral transtibial amputation, transfemoral amputation and able-bodied individuals completed 6 minutes of treadmill walking in consecutive blocks of 2 minutes at self-selected (SS) speed, 75% SS speed and 125% SS speed. Lower extremity kinematics were captured and hip–knee and knee–ankle CRPs were calculated. Statistical non-parametric mapping was applied and statistical significance was set at 0.05. Results The hip–knee CRP at 75% SS walking speed with the TD was larger in the amputated limb of participants with a transfemoral amputation compared to able-bodied individuals at the beginning and end of the gait cycle (p = 0.009). In people with a transtibial amputation, the knee–ankle CRP at SS and 125% SS walking speeds with the TD were smaller in the amputated limb at the beginning of the gait cycle compared to able-bodied individuals (p = 0.014 and p = 0.014, respectively). Additionally, no significant differences were found between both prostheses. However, visual interpretation indicates a potential advantage of the TD over the individual's current prosthesis. Conclusion This study provides lower-limb coordination patterns in people with a lower-limb amputation and reveals a possible beneficial effect of the TD over the individuals’ current prosthesis. Future research should include a well-sampled investigation of the adaptation process combined with the prolonged effects of the TD.

Human-Prosthetic Interaction (HumanIT): A study protocol for a clinical trial evaluating brain neuroplasticity and functional performance after lower limb loss

“…The data of the inertial measurement units will be used to evaluate coordination patterns between hip, knee and ankle joints or segments based on continuous relative phase plots. Biomechanical data will be analysed and purified in Matlab (The MathWorks Inc., Massachusetts, United States) following the methods described in Lathouwers et al (2023) [ 48 ].…”

Lower-extremity inter-joint coordination variability in active individuals with transtibial amputation and healthy males during gait

“…Complementing these findings, Cheng et al 14 demonstrated that a 12-week prosthetic gait training program can significantly enhance walking speed and limb coordination. Esposito et al 18 focused on pelvis-trunk coordination across different walking speeds, while Lathouwers et al 16 assessed gait patterns using an articulated passive ankle–foot prosthesis, highlighting areas for further research in joint coupling variability during gait in individuals with transfemoral and transtibial amputations. Collectively, these studies underscore the importance of nonlinear dynamic analysis in advancing our understanding of prosthetic gait dynamics.…”

Implementation of relative phase analysis to evaluate continuous interlimb coordination and stability in individuals with lower limb loss: Design and protocol for a retrospective analysis

“…Since different prosthetic devices may produce external perturbations to their system (ie, gait pattern), it is critical to determine the device that minimises these perturbations and allows the individual to reach his or her most stable walking pattern. While previous literature describes the application of relative phase (RP) analysis to individuals with lower limb loss,14–17 most of the studies focus on coordination between the pelvis and trunk,14 15 17 and one describes the intralimb (ie, within limb) coordination of the lower extremities 16. To date, only one study has investigated continuous gait interlimb (ie, between limbs) coordination and stability in individuals with lower limb loss 18.…”