Biomechanical Assessment of Gait in Lower-Extremity-Amputees

NCT ID: NCT01332123

Last Updated: 2016-06-09

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 10 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2011-04-30
• Study Completion Date: 2012-08-31

Brief Summary

This study is investigating the influence of several simulated real life conditions on the symmetry of gait with trans-tibial prostheses

Hypotheses: It is hypothesized that the observable differences in gait pattern between amputees can be detected by a combination of forces and moments that are measured internally in the prosthesis, and electromyography data. It is further hypothesized that changing conditions such as uneven walking surface, prosthetic misalignment or user fatigue are characterized by typical values in the measured data or combinations thereof.

Detailed Description

In amputee walking, an optimal static alignment of the artificial leg is important in order to achieve the best possible performance. Comfort, energy expenditure, mobility and walking speed should ideally be similar to those of able bodied persons. Of course, amputation level, overall health status and other factors often pose certain individual limitations that may prevent an amputee from reaching this goal.

Irrespective of that, the artificial leg must be aligned properly to eliminate unnecessary inhibitions. Apart from manufacturing a well fitting socket, and selecting the appropriate functional components of the prosthesis, the prosthetist has to routinely optimize the static alignment during the fitting process. Hereby, objective measures and guidelines are scarce. Despite various more or less useful tools that are available, the alignment optimization in praxis is often based on subjective gait assessment and rules of thumb. Commonly accepted is the notion, that the gait pattern should be most symmetrically, that is step lengths, stance times, knee angles etc. should be identical between sound and prosthetic leg.

There are different questions that our study wants to address: Is gait symmetry indeed a valid measure of prosthetic performance (e.i. is it the most energy efficient way to walk)? How does the gait pattern change when the prosthesis user walks on different surfaces, becomes tired or tries to compensate for a less-than-optimal prosthesis fit? How can gait symmetry be objectively assessed without using an expensive motion analysis laboratory? We hope that our findings will provide practically useful information that can help improve prosthetic fittings in the field.

The study will be based on data from up to 15 trans-tibial prosthesis users. Participants will walk with their standard prosthesis, which will be equipped with a small sensor unit for the measurement of forces and moments during walking. The muscle activity of the thigh muscles will be measured using surface EMG sensors. All of the data collection will take place at the USR facilities (115 E Reindl Way, Milwaukee), where a multi camera motion analysis system is set up. Trials will require an overall time commitment of 5 hours at most, and will include normal walking, walking on carpet and gravel, walking up and down stairs, walking with fatigued thigh muscles.

Conditions

Prosthesis User

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Blinding Strategy: NONE

Study Groups

Alignment perturbations

The following modifications will be applied to the prostheses: increased foot plantar flexion, increased foot dorsal flexion, increased foot supination, increased foot pronation (always 2 degrees from the neutral position)

Group Type: EXPERIMENTAL

Alignment perturbations

Intervention Type: DEVICE

Increased foot plantar flexion, increased foot dorsal flexion, increased foot supination, increased foot pronation (always 2 degrees from the neutral position)

Interventions

Alignment perturbations

Increased foot plantar flexion, increased foot dorsal flexion, increased foot supination, increased foot pronation (always 2 degrees from the neutral position)

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

• Trans tibial amputation
• Able to walk 30 minutes comfortably
• Modular prosthesis

Exclusion Criteria

• Prosthesis does not provide enough space between socket and foot module to fit the mobile measuring unit
• Physically or mentally unable to perform the required tasks

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 80 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

University of Wisconsin, Milwaukee

OTHER

Sponsor Role: lead

Responsible Party

Goeran Fiedler

Student-PI

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Brooke A Slavens, PhD

Role: PRINCIPAL_INVESTIGATOR

UWM CHS

Locations

USR, 115 E Reindl Way

Milwaukee, Wisconsin, United States

Countries

United States

Other Identifiers

UWM-11.254

Identifier Type: -

Identifier Source: org_study_id