The efficacy of the Ankle Mimicking Prosthetic Foot prototype 4.0 during walking: Physiological determinants

Evaluating the effectiveness of a novel prosthetic device during walking is an important step in product development.

To investigate the efficacy of a novel quasi-passive ankle prosthetic device, Ankle Mimicking Prosthetic Foot 4.0, during walking at different speeds, using physiological determinants in transtibial and transfemoral amputees.

Nonrandomized crossover design for amputees.

Six able-bodied subjects, six unilateral transtibial amputees, and six unilateral transfemoral amputees underwent a 6-min walk test at normal speed, followed by series of 2-min walking at slow, normal, and fast speeds. The intensity of effort and subjective measures were determined. Amputees performed all walking tests on a treadmill with current and novel prostheses. Shapiro-Wilk normality tests and parametric and nonparametric tests were conducted (p < 0.05).

Compared to able-bodied individuals, the rating of perceived exertion levels were significantly elevated in transtibial and transfemoral amputees for both prostheses (p ≤ 0.016). Compared to able-bodied individuals transfemoral amputees also showed significantly elevated heart rate for both prostheses at normal speed (p ≤ 0.043). Within-group comparisons demonstrated that walking with Ankle Mimicking Prosthetic Foot significantly increased the heart rate in transfemoral amputees and transtibial compared to current prosthesis (p = 0.002). Furthermore, transfemoral amputees reached a significantly higher rating of perceived exertion levels.

Intensity of effort during walking with Ankle Mimicking Prosthetic Foot is higher compared to current prostheses. Clinical relevance Ankle Mimicking Prosthetic Foot 4.0 is a novel quasi-passive ankle prosthesis with state-of-the-art technological parts. Subjective measures show the importance of this technology, but the intensity of effort during walking still remains higher compared to current passive prostheses, especially in transfemoral amputees.