Descriptive Study of Receptive Fields in Lower Limb Amputees

Descriptive Study of Receptive Fields in Lower Limb Amputees and the Effect of a Related Stimulation System on Selected Gait Parameters

It has been observed that patients subjected to amputations develop so called receptive fields, which time of occurrence and localization over time are yet not examined systematically.

This clinical trial aims to investigate the reliability in detecting these receptive fields as well as their incidence and changes over time.

Further it aims to evaluate the acute effect of a stimulating system ("Phantom Stimulator" (Cort X Sensorics, Spaichingen, Germany)) on selected gait parameters measured tough a gait analysis system ("OprtoGait" (Microgate, Bolzano, Italy)) as well as on phantom sensations measured through a questionnaire.

Study Overview

• Status: Unknown
• Conditions: Lower Limb Amputation Below Knee (Injury)
• Intervention / Treatment: Device: Phantom Stimulator, Cort X Sensorics, Spaichingen, Germany

Detailed Description

It has been observed that patients subjected to amputations develop so called receptive fields, which time of occurrence and localization over time are yet not examined systematically.

A receptive field is defined as skin area anywhere on the same side of the body as the amputation, which when stimulated by others, causes phantom sensations in the amputated extremity.

This clinical trial aims to investigate the reliability in detecting these receptive fields as well as their incidence and changes over time.

Further it aims to evaluate the acute effect of the stimulating system ("Phantom Stimulator" (Cort X Sensorics, Spaichingen, Germany)) on selected gait parameters measured tough a gait analysis system ("OprtoGait" (Microgate, Bolzano, Italy)) as well as on phantom sensations measured through a questionnaire.

• Study Type: Interventional
• Enrollment (Anticipated): 35
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • Aargau
    • Bellikon, Aargau, Switzerland, 5454
      • Rehaklinik Bellikon

Participation Criteria

Eligibility Criteria

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

Description

1. Inclusion criteria for descriptive study:

   a. Lower limb amputation (independently of side or height of amputation)

2. Inclusion criteria for Phantom stimulator:

   1. Receptive fields present at testing day 31 (last regular assessment of the receptive fields)
   2. Lower limb amputation below the knee (if both sides the system is applied to the dominant side).

3. Exclusion criteria:

   1. Implanted devices (defibrillator or pacemaker)
   2. Pregnancy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Screening
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: First setting ON; This arm performs the Gait analysis the first time after the familiarization phase with the stimulator in the modality ON. The second time the gait analysis is performed in the OFF modality.	Device: Phantom Stimulator, Cort X Sensorics, Spaichingen, Germany; This system consists of a pressure sensing insole connected to regular TENS-Electrode patches which are applied to the receptive fields of the patients (evoking the sensation of heel and forefoot). The individually adjusted stimulation intensity on the systems regulatory box through a socked screw is set at the beginning of the testing phase, and not changed anymore. The current is applied to mimic the roll-off-sensation while walking. This is done by locating two sets of electrodes on the receptive fields representing the heel and the ball of the foot respectively. Now the current is applied in an alternating manner coordinated with the walking of the participant. The coordination is made able through the pressure sensing insole.
Other: First setting OFF; This arm performs the Gait analysis the first time after the familiarization phase with the stimulator in the modality OFF. The second time the gait analysis is performed in the ON modality.	Device: Phantom Stimulator, Cort X Sensorics, Spaichingen, Germany; This system consists of a pressure sensing insole connected to regular TENS-Electrode patches which are applied to the receptive fields of the patients (evoking the sensation of heel and forefoot). The individually adjusted stimulation intensity on the systems regulatory box through a socked screw is set at the beginning of the testing phase, and not changed anymore. The current is applied to mimic the roll-off-sensation while walking. This is done by locating two sets of electrodes on the receptive fields representing the heel and the ball of the foot respectively. Now the current is applied in an alternating manner coordinated with the walking of the participant. The coordination is made able through the pressure sensing insole.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Description of receptive Fields Size in cm2	The primary outcomes are the changes in size over time. Here the size is described in cm2. The Fields size will be recorded by drawing them on the skin with eyeliner and subsequently taking photos. Later, these photos are analysed with the computer program Photoshop.	4-5 Weeks (7 hours)
Description of receptive Fields Position in % overlapping from first measurement	The primary outcomes are the changes in Position over time. Here the position is described in % overlapping with respect to the first measurement. The Fields position will be recorded by drawing them on the skin with eyeliner and subsequently taking photos. Later, these photos are put together and compared with the computer program Photoshop.	4-5 Weeks (7 hours)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in gait parameters through Phantom Stimulator	The secondary outcomes are the change in selected gait parameters through the application of the stimulating system ("Phantom Stimulator" (Cort X Sensorics, Spaichingen, Germany)). These parameters are measured with the gait analysis system Optogait. The selected parameters are step length (cm), width (cm), cadence (steps/min) and speed (m/s).	1/2 Day (3 hours)
Change in phantom sensations through Phantom Stimulator	The secondary outcomes are the change in phantom sensations through the application of the stimulating system ("Phantom Stimulator" (Cort X Sensorics, Spaichingen, Germany)). These changes are measured through a questionnaire witch uses the Visual Analogue Scale (values from 1 - 10).	1/2 Day (3 hours)

Collaborators and Investigators

• Sponsor: Rehaklinik Bellikon
• Collaborators: Cort X Sensorics GmbH
• Investigators: Principal Investigator: Marion Grögli, Dr. med., Reahklinik Bellikon

Publications and helpful links

Helpful Links

• Website of study site

Study record dates

Study Major Dates

• Study Start (Actual): October 27, 2017
• Primary Completion (Anticipated): June 1, 2018
• Study Completion (Anticipated): July 1, 2018

Study Registration Dates

• First Submitted: October 30, 2017
• First Submitted That Met QC Criteria: November 15, 2017
• First Posted (Actual): November 21, 2017

Study Record Updates

• Last Update Posted (Actual): November 21, 2017
• Last Update Submitted That Met QC Criteria: November 15, 2017
• Last Verified: November 1, 2017

More Information

Terms related to this study

• Keywords: Gait analysis; Amputation; Phantom Pain
• Other Study ID Numbers: 01_2017; 2017-01621 (Other Identifier: SNCTP (Swiss National Clinical Trials Portal))

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

IPD Plan Description

IPD is used only internally the study concerning the Phantom Stimulator (Cort X Sensorics, Spaichingen Germany). The IPD is shared with the responsible investigative parties of the Rehaklinik Bellikon only.

It will be available to the participant after completion of the study. The data obtained from the Study results in a publication after completion of the study.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No