While conventional wisdom holds that individuals with longer residual limbs retain greater function, they are actually confined to low-profile feet that limit performance. In particular, low-profile feet are often much stiffer than their standard profile counterparts. As such, many of the individuals with transtibial amputation that have long residual limbs are unable to obtain prosthetic feet that adequately meet their needs. This Phase I application describes a layered low-profile prosthetic foot for individuals with transtibial amputation that can achieve an unprecedented level of compliance without sacrificing strength. As a result of this novel design, preliminary work has shown energy storage and stiffness comparable to a standard height prosthetic foot in a package just one third the build height. The primary goal of this Phase I proposal is to conduct a multi-subject assessment of the value of the proposed prosthesis both relative to a range of standard profile feet, and also relative to commercially available low-profile feet. In order to do so, we propose the following aims: 1) design and test a family of layered low- profile feet for users up to 100 kg with foot sizes from 22 to 28 cm, 2) assess the biomechanical benefits of the layered low-profile foot with three transtibial prosthesis users with short residual limbs and three users with long residual limbs during level ground walking, and 3) assess the biomechanical function of the layered low-profile foot in a battery of activities of daily use.
Public Health Relevance Statement: PROJECT NARRATIVE We have developed a novel layered low-profile prosthetic foot that is able to provide enhanced compliance without sacrificing strength for individuals with transtibial amputation who have long residual limbs. It is hypothesized that the proposed prosthesis will offer similar benefits to these individuals as comparable higher profile prostheses offer users with shorter residual limbs. The primary goal of this Phase I proposal is to assess the degree to which the proposed prosthesis can provide benefits to prosthesis users in this population, along with characterizing the degree to which the novel prosthesis emulates its taller counterparts.
Project Terms: Activities of everyday life; daily living function; daily living functionality; functional ability; functional capacity; Activities of Daily Living; Amputation; Anatomic Sites; Anatomic structures; Anatomy; Regio tarsalis; Ankle; Behavior; Biomechanics; biomechanical; Body Regions; Compliant Behaviors; Family; Feedback; foot; Gait; Goals; Human; Modern Man; Kinetics; Knee Prosthesis; artificial knee; prosthetic knee; Modernization; Movement; body movement; Orthotic Devices; Orthosis; orthotics; Stress; Surveys; Survey Instrument; Target Populations; Testing; Weight; weights; Work; Measures; Walking; measurable outcome; outcome measurement; Outcome Measure; Prosthetic device; Prosthetics; Prosthesis; improved; Phase; Series; Individual; satisfaction; light weight; lightweight; Shapes; Knowledge; Adopted; Protocols documentation; Protocol; Height; experience; Performance; kinematics; kinematic model; Structure; novel; Participant; Categories; Devices; theories; Manufacturer; Length; Observational Study; Observation research; Observation study; Observational research; Process; designing; design; new approaches; novel approaches; novel strategy; novel strategies; Outcome; Population; prototype; primary outcome; standard of care; prosthesis user; prosthetic user; prosthetic wearer; prosthesis wearer; artificial foot; foot prosthesis; prosthetic feet; prosthetic foot; residual limb; walking pace; walking speed; experiment; experimental research; experiments; experimental study; biomechanical test; biomechanical analyses; biomechanical analysis; biomechanical assessment; biomechanical characterization; biomechanical evaluation; biomechanical measurement; biomechanical profiling
