NCT02026570

Brief Summary

Objectives: The purpose of this study is to investigate attentional (internal vs. external) focus effects on persons with amputation to perform a defined compensatory movement to reduce the likelihood of a fall. An internal focus of attention directs a person's conscious attention to their body's movements, whereas an external focus of attention directs a person's conscious attention to the effects of their movements or specific features in the environment. Numerous experiments have investigated the effects of an internal and external focus of attention on motor performance and the findings are in favor of an external focus of attention. In our work, we propose a motor learning research experiment to evaluate attentional focus strategies on the rehabilitation outcomes of learning and adaptation to the new proprioceptive information for persons with a recent transtibial amputation. Research Design and Methodology: For this pilot study, six participants with recent unilateral transtibial amputation will be recruited. Four participants will receive internal and external focus of attention training methods while the other two (control group) will receive standard prosthetic training instructions. The experiment will be conducted in three phases: Phase 1 -- Baseline Performance Test, Phase 2 -- Training sessions, and Phase 3 - Learning Test. The training will utilize a vibrotactile device designed to generate tactile sensations at the skin-socket interface simulating contact of the prosthesis with the environment. The sensation simulates a perturbation that signals a potential fall event. During the experiment the augmented sensory information will be introduced randomly while participants walk at a preferred pace on a level surface. Movement kinematics and kinetics of the body will be recorded for analyses using a motion capture system with force plates. Finding: It is hypothesized that the external focus of attention condition will outperform the internal focus of attention condition when responding to perturbations. The external focus of attention condition will yield faster response time and show improved compensatory responses compared to the internal focus of attention group by producing a greater lateral displacement of the artificial limb relative to the line of progression. In addition, the external condition will demonstrate a greater step length and step height than the internal focus of attention condition when provided with a perturbation. Clinical Significance: Current practices within the field of Physical Therapy reveal that there is little therapeutic intervention for fall prevention. Instructions are traditionally provided on how to reduce the risk of falling through preparation of a room or obstacle avoidance or on the proper way to fall to decrease injury. However, there are no protocols for providing a prosthetic user with compensatory strategies to avoid a fall after a perturbation occurs. The research findings can result in improved training protocols, which can improve rehabilitative outcome. Impact/Significance: The growing number of prosthetic users presents a need for improved patient care and effective prosthetic training and rehabilitation methods. Complimentary to the mission of the VA, the results of this research could enhance the quality of patient care and further assist these patients toward becoming prosthetically rehabilitated.

Trial Health

43
At Risk

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
6

participants targeted

Target at below P25 for not_applicable

Timeline
Completed

Started Jun 2013

Longer than P75 for not_applicable

Geographic Reach
1 country

1 active site

Status
unknown

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

June 1, 2013

Completed
7 months until next milestone

First Submitted

Initial submission to the registry

December 19, 2013

Completed
15 days until next milestone

First Posted

Study publicly available on registry

January 3, 2014

Completed
1.2 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

March 1, 2015

Completed
4.4 years until next milestone

Study Completion

Last participant's last visit for all outcomes

August 1, 2019

Completed
Last Updated

April 5, 2019

Status Verified

April 1, 2019

Enrollment Period

1.7 years

First QC Date

December 19, 2013

Last Update Submit

April 3, 2019

Conditions

Keywords

ProsthesisFallsTraining

Outcome Measures

Primary Outcomes (1)

  • Reaction Time

    Time for subject to laterally displace Center of Mass two standard deviations from normative trajectory following stimulus.

    Five visits over a three week period.

Secondary Outcomes (1)

  • Movement Time

    Five visits over a three week period.

Study Arms (3)

Control

NO INTERVENTION

Persons with unilateral transtibial amputation receiving standard physical therapy.

Motor Control Internal Focus

EXPERIMENTAL

Persons with unilateral transtibial amputation receiving standard physical therapy and additional training with motor control internal focus of attention instructions.

Behavioral: Internal Focus of Attention

Motor Control External Focus

EXPERIMENTAL

Persons with unilateral transtibial amputation receiving standard physical therapy and additional training with external focus of attention instructions.

Behavioral: External Focus of Attention

Interventions

Providing instructions for the user to manipulate their residual limb in space during standing and walking tasks.

Motor Control Internal Focus

Providing instructions for the user to manipulate their prosthetic foot in space during standing and walking tasks.

Motor Control External Focus

Eligibility Criteria

Age18 Years - 70 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Undergone amputation within the past year.
  • Currently undergoing prosthetic training in Physical Therapy utilizing a prosthesis.
  • Be within two weeks of completing prosthetic training in Physical Therapy.
  • Ability to tolerate walking for a minimum of 100 yards over the course of a four hour time period with or without resting.
  • No current skin breakdown on the residual limb.

You may not qualify if:

  • Not cleared by Physical Therapy to use the prosthesis without contact precautions.
  • Any medical or psychosocial condition that, in the opinion of the investigator, could jeopardize the subject's participation, and compliance with the study criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

V.A. Long Beach Healthcare System

Long Beach, California, 90822, United States

Location

Related Publications (15)

  • Clippinger FW, Seaber AV, McElhaney JH, Harrelson JM, Maxwell GM. Afferent sensory feedback for lower extremity prosthesis. Clin Orthop Relat Res. 1982 Sep;(169):202-6.

    PMID: 7105581BACKGROUND
  • D. J. DiLorenzo, D. J. Edell, M. J. Koris, and R. R. Riso, "Chronic intraneural electrical stimulation for prosthetic sensory feedback," 1st IEEE EMBS Conference on Neural Engineering, pp:116-119, 2003.

    BACKGROUND
  • Doubler JA, Childress DS. An analysis of extended physiological proprioception as a prosthesis-control technique. J Rehabil Res Dev. 1984 May;21(1):5-18.

    PMID: 6527290BACKGROUND
  • Fan RE, Culjat MO, King CH, Franco ML, Boryk R, Bisley JW, Dutson E, Grundfest WS. A haptic feedback system for lower-limb prostheses. IEEE Trans Neural Syst Rehabil Eng. 2008 Jun;16(3):270-7. doi: 10.1109/TNSRE.2008.920075.

    PMID: 18586606BACKGROUND
  • Kaczmarek KA, Webster JG, Bach-y-Rita P, Tompkins WJ. Electrotactile and vibrotactile displays for sensory substitution systems. IEEE Trans Biomed Eng. 1991 Jan;38(1):1-16. doi: 10.1109/10.68204.

    PMID: 2026426BACKGROUND
  • Kadkade PP, Benda BJ, Schmidt PB, Wall C 3rd. Vibrotactile display coding for a balance prosthesis. IEEE Trans Neural Syst Rehabil Eng. 2003 Dec;11(4):392-9. doi: 10.1109/TNSRE.2003.819937.

    PMID: 14960115BACKGROUND
  • G.E. Loeb and F.J. Richmond. BION Implants for Therapeutic and Functional Electrical Stimulation. Neural Prostheses for Restoration of Sensor and Motor Function. CRC Press, Boca Raton, FL, 2000. R.A. Magill. "Motor Learning and Control: Concepts and Applications," (9th ed.). New York, NY: McGraw Hill, 2011

    BACKGROUND
  • Miller WC, Speechley M, Deathe B. The prevalence and risk factors of falling and fear of falling among lower extremity amputees. Arch Phys Med Rehabil. 2001 Aug;82(8):1031-7. doi: 10.1053/apmr.2001.24295.

    PMID: 11494181BACKGROUND
  • J.A. Sabolich and G.M. Ortega. "Sense of feel for lower-limb amputees: A phase-one study," Journal of Prosthetics and Orthotics, 6(2):36-41, 1994

    BACKGROUND
  • J.A. Sabolich, G.M. Ortega, and G.B. Schwabe. "System and method for providing a sense of feel in a prosthetic or sensory impaired limb," United States Patent, December 31, 2002

    BACKGROUND
  • D.C. Simpson. "The choice of control system for the multimovement prosthesis: extended physiological proprioception (EPP), " In: The Control of Upper-Extremity Prostheses and Orthoses. Springfiled, Illinois, C.C Thomas. pp:146-150, 1974

    BACKGROUND
  • D.C. Simpson. "The control and supply of a multimovement externally powered upper limb prosthesis," Proc 4th Ini Symp External Control of Human Extremities. Belgrade, Yugoslav Committee for Electronics and Autotlon. pp:247-254, 1973

    BACKGROUND
  • Wulf G, Prinz W. Directing attention to movement effects enhances learning: a review. Psychon Bull Rev. 2001 Dec;8(4):648-60. doi: 10.3758/bf03196201.

    PMID: 11848583BACKGROUND
  • Yoshida K, Horch K. Closed-loop control of ankle position using muscle afferent feedback with functional neuromuscular stimulation. IEEE Trans Biomed Eng. 1996 Feb;43(2):167-76. doi: 10.1109/10.481986.

    PMID: 8682528BACKGROUND
  • D. Zambarbieri, M. Schmid, and G. Verni. "Sensory feedback for lower limb prosthesis", in Intelligent Systems and Technologies in Rehabilitation Engineering, Ed. H.L. Teodorescu and L. Jain, CRC Press, Boca Raton, 2001

    BACKGROUND

Study Officials

  • Dana D. Craig, M.A.

    V.A. Long Beach Healthcare System

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
NONE
Purpose
OTHER
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Health System Specialist

Study Record Dates

First Submitted

December 19, 2013

First Posted

January 3, 2014

Study Start

June 1, 2013

Primary Completion

March 1, 2015

Study Completion

August 1, 2019

Last Updated

April 5, 2019

Record last verified: 2019-04

Locations