Prosthetic Components and Stability in Amputee Gait

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
Department of Veterans Affairs
ClinicalTrials.gov Identifier:
NCT00167778
First received: July 1, 2005
Last updated: September 4, 2013
Last verified: September 2013
  Purpose

The biomechanics of changing direction while walking has been largely neglected despite its relevancy to functional mobility. In addition, an increased risk of injury can be associated with turning due to a decrease in stability. The objective of this study is to understand the biomechanics of turning gait in sample populations of intact and trans-tibial amputees and the capacity of prosthetic components to facilitate transverse plane movement. The clinical impact of this investigation is the development of interventions that increase functional mobility, stability and safety while turning.

The researchers propose to investigate three sets of hypotheses. The first set addresses the fundamental biomechanical mechanisms associated with walking along a circular trajectory, how intact subjects differ from amputees, and the effect of a rotation adaptor pylon. The second set of hypotheses addresses dynamic stability and the potential influence of prosthetic interventions. The third set of hypotheses addresses how the rotational properties of the prosthetic pylon can influence comfort and mobility during daily activities.


Condition Intervention
Diabetes Mellitus
Leg Injuries
Traumatic Amputation
Device: Transverse plane rotation adaptor pylon
Device: Rigid pylon

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Single Blind (Subject)
Primary Purpose: Treatment
Official Title: Turning Corners: Prosthetic Components and Stability in Amputee Gait

Resource links provided by NLM:


Further study details as provided by Department of Veterans Affairs:

Primary Outcome Measures:
  • Transverse plane torque [ Time Frame: Measurements will occur following a three week acclimation period for each intervention ] [ Designated as safety issue: No ]

Estimated Enrollment: 40
Study Start Date: January 2005
Study Completion Date: September 2008
Primary Completion Date: September 2008 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Arm 1
Novel prosthetic pylon
Device: Transverse plane rotation adaptor pylon
Potential future practice
Active Comparator: Arm 2
rigid pylon
Device: Rigid pylon
Current clinical practice

Detailed Description:

Most of what is known about how amputees walk and how the properties of prosthetic components affect their gait has been discovered through sagittal plane observations while amputees walk back and forth along a straight line. Abnormal limb loading, thought to be a principal factor in the occurrence of residual limb pain which in turn may cause instability and limit mobility, can certainly occur while walking in a straight line. However, the incidence of abnormal limb loading is likely amplified when performing more complex gait activities, such as turning or avoiding obstacles; activities that are so very common in everyday life.

The specific aims of this investigation are to:

  1. discover the biomechanical strategies used and the stability of both intact individuals and trans-tibial amputees walking along a circular trajectory and
  2. explore the effects of a prosthetic intervention on turning biomechanics, stability, comfort, and mobility.

We propose to investigate three sets of hypotheses:

The first set of hypotheses addresses the fundamental biomechanical mechanisms associated with walking along a circular trajectory, how intact subjects differ from amputees, and the effect of a rotation adaptor pylon. We will conduct experiments to test three hypotheses related to achieving a change of heading, orientation, and balancing of centripetal forces necessary to walk along a circular trajectory.

The second set of hypotheses seeks to identify whether trans-tibial amputees with a rigid pylon are more unstable during a turning task than non-amputees and whether or not the rotation adaptors enhance stability. We will conduct experiments to calculate an index of dynamic stability that measures the rate at which a person can respond to a perturbation and return to a stable gait pattern.

The third set of hypotheses addresses how the rotational properties of the prosthetic pylon can influence comfort and mobility during daily activities. To measure comfort and mobility, we will solicit questionnaire responses and step count measures from amputees after a one-month period of wearing a rigid pylon and after a one-month period of wearing a transverse plane rotation adaptor (within-subject comparison). In addition to these field measurements, we will also compare the distance traveled during a six-minute walk. Patient opinions about their prosthesis and mobility measures over long periods of time can play a significant role in prosthesis evaluation.

For veteran amputees who experience discomfort and increased risk for residual limb skin problems, it seems reasonable to suppose that these problems might occur when walking along a curved trajectory rather than just a straight line. The joint forces and moments of turning may differ significantly from those exhibited while walking in a straight line. The proposed research will create a new knowledge base with which to understand prosthetic intervention effectiveness. The immediate clinical impact for the trans-tibial amputee is the determination if transverse plane rotational adapter pylons can improve their comfort, mobility, and stability.

  Eligibility

Ages Eligible for Study:   18 Years to 70 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Amputee Subjects:

    • be a unilateral trans-tibial amputee between the ages of 18 and 70,
    • weigh 220 pounds or less,
    • have been fit with a prosthesis and using a prosthesis for at least two years,
    • wear the prosthesis for at least 8 hours per day,
    • walk without crutches or a walker,
    • able to walk outside the home and in the community,
    • have not fallin within the last six months,
  • Non-amputee subjects participating in this investigation will meet similar inclusion criteria except for those related to prosthesis use.

Exclusion Criteria:

  • Amputee Subjects:

    • amputation due to tumor, have an active tumor, or are undergoing treatment of a tumor,
    • have pain in legs or any condition that interferes with walking.
  • Non-amputee subjects participating in this investigation will meet similar exclusion criteria except for those related to cause of amputation.
  Contacts and Locations
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Please refer to this study by its ClinicalTrials.gov identifier: NCT00167778

Locations
United States, Washington
VA Puget Sound Health Care System, Seattle
Seattle, Washington, United States, 98108
Sponsors and Collaborators
Investigators
Principal Investigator: Glenn K. Klute, PhD VA Puget Sound Health Care System, Seattle
  More Information

No publications provided

Responsible Party: Department of Veterans Affairs
ClinicalTrials.gov Identifier: NCT00167778     History of Changes
Other Study ID Numbers: A3611-R
Study First Received: July 1, 2005
Last Updated: September 4, 2013
Health Authority: United States: Federal Government

Keywords provided by Department of Veterans Affairs:
Amputation
Amputee
Artificial limbs
Gait
Locomotion
Walking

Additional relevant MeSH terms:
Amputation, Traumatic
Diabetes Mellitus
Leg Injuries
Wounds and Injuries
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases

ClinicalTrials.gov processed this record on July 24, 2014