Transtibial Amputation - Unilateral Clinical Trial
Official title:
Comparative Performance of Dynamic Elastic Response Feet
The purpose of this study was to compare the functional performance of individuals with transtibial amputation using two types of prosthetic foot designs: carbon fiber vs. fiberglass composite.
Recently, a new type of prosthetic foot has appeared on the market. This device is composed
of a fiberglass composite material. Knowledge is lacking regarding the performance
characteristics of this new device. Comprehensive studies are needed to form a solid basis
for prosthetic prescription. The current study sought to understand the experience of
community-living, transtibial amputees using this prosthetic foot. Specifically, the
biomechanical performance of this device were compared to existing conventional dynamic
elastic response (DER) technology in a controlled laboratory setting. The investigators
hypothesized that the fiberglass composite material provided more energy return and improved
ankle kinematics performance.
The study design was a repeated measures cross-over trial whereby only the prosthetic foot
was changed. Each subject was tested using their current carbon-fiber energy storage and
return prosthetic foot (CFPF) and the fiberglass composite energy storage and return
prosthetic foot (Rush, Ability Dynamics) (FPF). Half of the subjects began the study on the
CFPF while the other half began on the FPF. All types of CFPF were used in this study. Each
subject was given an acclimation period (about 4 weeks) before testing, which was consistent
with other similar studies. The same socket and suspension were used throughout the study in
order to eliminate these confounding variables.
A 10 camera, high resolution motion capture system with a set of 51 reflective markers was
used to capture whole-body motion. Three-dimensional marker trajectory data was collected at
120 Hz and filtered using a fourth-order Butterworth low-pass filter with a cutoff frequency
of 8 Hz. The standard Helen Hayes marker set and some additional markers were applied to the
subject. Additional markers included an anterior pylon marker, medial pylon marker, lateral
pylon marker, right and left medial calcaneus markers, and right and left lateral calcaneus
markers. In addition, left and right medial knee markers were used for establishing the knee
joint centers and were then removed for the walking trails. Subjects wore standard laboratory
athletic shoes for all walking trials. All of the markers associated with the foot were
placed on the outside of the subject's shoes.
Following the application of the reflective marker set, the subject performed tests while
walking over level ground at a self-selected and normalized speed as well as up and down a 10
degree inclined ramp. The normalized speed controlled for leg length by normalizing to a
Froude (Fr) number of 0.25 where Fr = v^2/gl, and v is the walking speed, g is the
gravitational constant, and l is the leg length using the greater trochanter height as leg
length. Timing gates were used to control the walking speed. Simultaneously, ground reaction
force data was collected from force plates at a sampling rate of 600 Hz. Data from these
force plates was time-synchronized with the motion cameras. The ramp had a force plate
embedded within the ramp.
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| Status | Clinical Trial | Phase | |
|---|---|---|---|
| Enrolling by invitation |
NCT05964855 -
Comparison of Various Prosthetic Foot-Ankle Mechanisms
|
N/A |