Transfemoral prosthesis users demonstrate a higher fall rate due to tripping than able-bodied controls in previous laboratory studies. In particular, early swing demonstrates the greatest disparity, where able-bodied controls typically utilize an elevating strategy to cross the obstacle in the same stride that the perturbation occurs, rather than the lowering strategy, where swing is ended prematurely and the obstacle is crossed in the following stride. However, due to the passive nature of most commercial knee prostheses, the elevating strategy is largely inaccessible to prosthesis users, potentially contributing to the increased fall rate in early swing. To investigate the effects of reintroducing the elevating strategy to transfemoral prosthesis users, a bimodal stumble recovery controller was developed for a powered knee prosthesis that utilized the elevating and lowering recovery strategies, selected based on the post-impact kinematics of the prosthesis. The Bimodal controller was compared to a unimodal controller that only used the lowering strategy. Three transfemoral prosthesis users underwent a series of treadmill-based obstacle perturbations with each controller following an acclimation period. All participants successfully used the elevating response in the early swing phase. On average, the elevating response reduced the disturbance to participants’ trunk kinematics and the reliance on harness support. While the Bimodal controller sometimes resulted in a recovery strategy mismatch for two participants, the mismatch still resulted in outcome metrics comparable to the unimodal controller. Overall, results suggest that the inclusion of the elevating and lowering strategies may improve stumble recovery outcomes for some transfemoral prosthesis users.

The objectives of the present study were (a) to determine the effects of a 12-week intervention using wearables promoted through physical education classes on physical activity, body composition, physical fitness and psychological well-being of overweight or obese adolescents; and (b) to analyze the differences in outcomes based on gender and baseline physical activity. Seventy-three overweight and obese adolescents (mean age: 13.44 ± 1.12 years) were randomly assigned to an experimental group (EG) or control group (CG). The EG used a physical activity wearable for 12 weeks. Both groups were assessed before and after the intervention. Regarding primary outcomes, the EG showed an increase in physical activity (p = 0.048) and reductions in body mass index (p = 0.007), fat mass (p < 0.001), and sum of 3 skinfolds (p = 0.002), with moderate-to-large effect sizes (η2 > 0.09). According to the secondary outcomes, improvements in physical fitness were limited, with increases observed only in abdominal muscular endurance, and these changes were also present in the CG. Subgroup analyses showed that females and adolescents with low baseline physical activity experienced greater benefits, particularly in fat-related variables (p < 0.001–0.037), with large effect sizes (η2 > 0.14). Additionally, adolescents with greater exposure to the wearable-based intervention showed more consistent improvements in fat-related outcomes (p < 0.001–0.032), with large effect sizes (η2 > 0.25). In conclusion, a wearable-based intervention promoted through physical education classes may contribute to meaningful improvements in body composition, particularly among females and previously inactive adolescents who are overweight or obese. However, effects on physical fitness and psychological well-being were limited, highlighting the importance of intervention design, adherence, and complementary motivational strategies.

Individuals with limb loss present significant challenges to testing and evaluating prosthetic devices, such as medical approval processes and participant availability. Prosthesis simulators, designed for mimicking prosthesis use with able-bodied individuals, offer an alternative to conducting controlled experiments and enhancing the development of prosthetic technologies. This review examines the design features, applications, and limitations of lower limb prosthesis simulators. A literature search identified 73 studies that have used lower limb prosthesis simulators. Most studies have focused on transfemoral prosthesis simulators (TFsims) and testing prosthetic designs and control mechanisms. The most frequently assessed movement was walking, while other movements, were explored only sporadically. The findings reveal significant variability in simulator configurations, training protocols, and the range of movements assessed. Additionally, a notable research gap exists in evaluations of the effect of transtibial prosthesis simulators (TTsims) and hip disarticulation prosthesis simulators (HDsims) on gait. Despite these challenges, prosthesis simulators offer promising potential for accelerating and improving prosthesis development while putting less stress on the relatively small target group of individuals with limb loss. Further research is needed to standardize methodologies and better understand the effects of simulator design and training on gait performance to facilitate advancements in prosthetic research.

Ankle-foot mechanisms are designed to substitute for missing anatomical behavior of lower-limb prosthesis users. Historically, the majority of ankle-foot mechanism research has been focused on transtibial prosthesis users despite evidence that current knowledge is not directly translated to transfemoral prosthesis users, such as the influence of single-axis knee alignment during gait and the differences in standing balance management. This review attempts to characterize the current state of published knowledge about the effects of ankle-foot prosthesis design on standing and walking performance in transfemoral prosthesis users. The databases of PubMed, Embase, Cochrane Library, CINAHL, and IEEE Xplore were searched on January 6, 2025. Data from the selected articles were extracted and reported following the PRISMA extension for scoping reviews. Thirty-five articles were included that reported on seven different types of feet, ranging from simple designs like a solid ankle-cushioned heel (SACH) foot to more complex ones such as a microprocessor foot. The range of reported study tasks extended from standing and level walking to more complex tasks like incline/decline slopes and parcourse walking. The results suggest some parallels between transfemoral and transtibial prosthesis users, such as improvements with the incorporation of roll-over-shape (ROS) features and adaptation of a hydraulic ankle. The literature also emphasized how ankle-foot components affect ground force vector position and direction, influencing prosthetic knee control, highlighting the importance of considering the interaction between the prosthetic ankle-foot and knee mechanisms. Understanding these interactions will support the development of clinical practice guidelines by identifying the pair of prosthetic components that maximizes performance.