Dataset Information

Robotic lower limb prosthesis design through simultaneous computer optimizations of human and prosthesis costs.

ABSTRACT: Robotic lower limb prostheses can improve the quality of life for amputees. Development of such devices, currently dominated by long prototyping periods, could be sped up by predictive simulations. In contrast to some amputee simulations which track experimentally determined non-amputee walking kinematics, here, we explicitly model the human-prosthesis interaction to produce a prediction of the user's walking kinematics. We obtain simulations of an amputee using an ankle-foot prosthesis by simultaneously optimizing human movements and prosthesis actuation, minimizing a weighted sum of human metabolic and prosthesis costs. The resulting Pareto optimal solutions predict that increasing prosthesis energy cost, decreasing prosthesis mass, and allowing asymmetric gaits all decrease human metabolic rate for a given speed and alter human kinematics. The metabolic rates increase monotonically with speed. Remarkably, by performing an analogous optimization for a non-amputee human, we predict that an amputee walking with an appropriately optimized robotic prosthesis can have a lower metabolic cost--even lower than assuming that the non-amputee's ankle torques are cost-free.

SUBMITTER: Handford ML

PROVIDER: S-EPMC4746571 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Robotic lower limb prosthesis design through simultaneous computer optimizations of human and prosthesis costs.

Handford Matthew L ML Srinivasan Manoj M

Scientific reports 20160209

Robotic lower limb prostheses can improve the quality of life for amputees. Development of such devices, currently dominated by long prototyping periods, could be sped up by predictive simulations. In contrast to some amputee simulations which track experimentally determined non-amputee walking kinematics, here, we explicitly model the human-prosthesis interaction to produce a prediction of the user's walking kinematics. We obtain simulations of an amputee using an ankle-foot prosthesis by simul ...[more]

PMID: 26857747

Similar Datasets

Project description:ObjectiveTo evaluate the content, construct, and discriminant validity of the Narrowing Beam Walking Test (NBWT), a performance-based balance test for lower limb prosthesis users.DesignCross-sectional study.SettingResearch laboratory and prosthetics clinic.ParticipantsUnilateral transtibial and transfemoral prosthesis users (N=40).InterventionsNot applicable.Main outcome measuresContent validity was examined by quantifying the percentage of participants receiving maximum or minimum scores (ie, ceiling and floor effects). Convergent construct validity was examined using correlations between participants' NBWT scores and scores or times on existing clinical balance tests regularly administered to lower limb prosthesis users. Known-groups construct validity was examined by comparing NBWT scores between groups of participants with different fall histories, amputation levels, amputation etiologies, and functional levels. Discriminant validity was evaluated by analyzing the area under each test's receiver operating characteristic (ROC) curve.ResultsNo minimum or maximum scores were recorded on the NBWT. NBWT scores demonstrated strong correlations (ρ=.70‒.85) with scores/times on performance-based balance tests (timed Up and Go test, Four Square Step Test, and Berg Balance Scale) and a moderate correlation (ρ=.49) with the self-report Activities-specific Balance Confidence scale. NBWT performance was significantly lower among participants with a history of falls (P=.003), transfemoral amputation (P=.011), and a lower mobility level (P<.001). The NBWT also had the largest area under the ROC curve (.81) and was the only test to exhibit an area that was statistically significantly >.50 (ie, chance).ConclusionsThe results provide strong evidence of content, construct, and discriminant validity for the NBWT as a performance-based test of balance ability. The evidence supports its use to assess balance impairments and fall risk in unilateral transtibial and transfemoral prosthesis users.

Project description:IntroductionAdverse events after a lower limb amputation (LLA) can negatively affect the rehabilitation process and may lead to emergency department (ED) visits. Earlier receipt of a prosthesis, as compared to delayed or not receiving a prosthesis, may decrease or moderate the risk of increased ED utilization. In addition, adverse events (ie, fall-related injury [FRI]) may be associated with increased health care utilization as measured by ED use. The implication of the timing of prosthesis provision after amputation and reduced ED use is not well established. Obtaining data about ED utilization early post-LLA could assist the rehabilitation team in ensuring timely and appropriate access to improve outcomes.ObjectiveTo determine the role that timing of prosthesis receipt has in ED utilization and the association of fall/FRI with health care utilization.DesignRetrospective observational cohort using commercial claims data. A logistic regression model was used to assess factors that influence ED utilization post-LLA.SettingWatson/Truven administrative database 2014 to 2016.ParticipantsThe study sample consisted of 510 adults age 18 to 64 years with continuous enrollment for 3 years.InterventionsIndependent variables included age, sex, diabetes status, amputation level, fall diagnosis, and prosthesis receipt. Fall was defined as presence of a diagnosis code in any outpatient procedure after the amputation date.Main outcome measureED use after amputation was defined as the presence of procedure codes that billed for ED services (99281 to 99285).ResultsIndividuals who receive a prosthesis early, within 0 to 3 months, post-LLA were 48% (odds ratio [OR] 0.52, 95% confidence interval [CI] 0.28 to 0.97) less likely to use the ED compared to those who did not receive a prosthesis. Individuals who experienced a fall/FRI had 2.8 (OR 2.86, 95% CI 1.23 to 6.66) times the odds of ED utilization.ConclusionReceipt of a prosthesis reduces the risk of ED use. The current study underscores the value of prostheses during the rehabilitation process after LLA.

Dataset Information

Robotic lower limb prosthesis design through simultaneous computer optimizations of human and prosthesis costs.

Publications

Robotic lower limb prosthesis design through simultaneous computer optimizations of human and prosthesis costs.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets