Enhancement of Residual Limb Proprioception and Rehabilitation Training Methods With a Vibrotactile Device.

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.

Study Overview

• Status: Unknown
• Conditions: Transtibial Amputation
• Intervention / Treatment: Behavioral: Internal Focus of Attention; Behavioral: External Focus of Attention

• Study Type: Interventional
• Enrollment (Anticipated): 6
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • Long Beach, California, United States, 90822
      • V.A. Long Beach Healthcare System

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• 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.

Exclusion Criteria:

• 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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: Control; Persons with unilateral transtibial amputation receiving standard physical therapy.
Experimental: Motor Control Internal Focus; 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; Providing instructions for the user to manipulate their residual limb in space during standing and walking tasks.
Experimental: Motor Control External Focus; Persons with unilateral transtibial amputation receiving standard physical therapy and additional training with external focus of attention instructions.	Behavioral: External Focus of Attention; Providing instructions for the user to manipulate their prosthetic foot in space during standing and walking tasks.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
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 Outcome Measures

Outcome Measure	Measure Description	Time Frame
Movement Time	Time from reaction time to completion of task, which is a side step following stimulus.	Five visits over a three week period.

Collaborators and Investigators

• Sponsor: Southern California Institute for Research and Education
• Collaborators: California State University, Long Beach; California State University, Dominguez Hills
• Investigators: Principal Investigator: Dana D. Craig, M.A., V.A. Long Beach Healthcare System

Publications and helpful links

General Publications

• 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.
• 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.
• 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.
• 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.
• 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.
• 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.
• 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
• 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.
• 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
• 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
• 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
• 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
• 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.
• 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.
• 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

Study record dates

Study Major Dates

• Study Start (Actual): June 1, 2013
• Primary Completion (Actual): March 1, 2015
• Study Completion (Anticipated): August 1, 2019

Study Registration Dates

• First Submitted: December 19, 2013
• First Submitted That Met QC Criteria: December 31, 2013
• First Posted (Estimate): January 3, 2014

Study Record Updates

• Last Update Posted (Actual): April 5, 2019
• Last Update Submitted That Met QC Criteria: April 3, 2019
• Last Verified: April 1, 2019

More Information

Terms related to this study

• Keywords: Training; Prosthesis; Falls
• Other Study ID Numbers: 01234