Clinical trial NCT02542761: Comparative Performance of Dynamic Elastic Response Feet
Official title: Comparative Performance of Dynamic Elastic Response Feet
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Transtibial Amputation - Unilateral
Lead sponsor: Mayo Clinic
Sponsor class: OTHER
First posted: 2015-09-07
Enrollment: 10
Sex: ALL
Minimum age (years): 21
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NON_RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: This was a repeated measures cross-over trial whereby only the prosthetic foot was changed. Each subject was tested using their current carbon-fiber prosthetic foot (CFPF), and the fiberglass prosthetic foot (FPF). Half of the subjects began the study on the CFPF while the other half began on the FPF. Each subject was given an acclimation period of 4 weeks before testing.
Primary purpose: TREATMENT

Brief summary: 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.

Detailed description: 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.

Eligibility criteria: Inclusion Criteria:

* Unilateral transtibial amputee
* Currently using a carbon fiber prosthetic (DER) foot for at least the last 6 months
* Stable stump volume over the past 6 months
* Medicare Functional Classification Level K3 or K4

Exclusion Criteria:

* Neuromuscular problems such as previous stroke or contralateral amputation
* Use of gait aids for ambulation
* Undergoing dialysis
* Poor prosthetic socket fit or stump problems (e.g., skin breakdown)

Primary outcomes:
measure: Peak Ankle Dorsiflexion During Stance
timeFrame: After approximate 4 week acclimation period
Secondary outcomes:
measure: Peak Ankle Plantar Flexor Moment During Stance
timeFrame: After approximate 4 week acclimation period
measure: Peak Ankle Power Generation
timeFrame: After approximate 4 week acclimation period
measure: Peak Knee Flexion During Swing
timeFrame: After approximate 4 week acclimation period
measure: Time of Peak Knee Flexion During Swing
timeFrame: After approximate 4 week acclimation period
measure: Patient Satisfaction as Measured by the Prosthesis Evaluation Questionnaire (PEQ)
timeFrame: After approximate 4 week acclimation period
Other outcomes:
Locations:
city: Rochester
country: United States
facility: Mayo Clinic
state: Minnesota
Study officials:
affiliation: Mayo Clinic
name: Kenton R Kaufman, PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Kaufman KR, Bernhardt K. Functional performance differences between carbon fiber and fiberglass prosthetic feet. Prosthet Orthot Int. 2021 Jun 1;45(3):205-213. doi: 10.1097/PXR.0000000000000004.