apta parametros fes
TRANSCRIPT
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Functional Electrical Stimulation Programs
for People with SCI: Clinician and Consumer
Perspectives for Clinic and Home
January 22, 2013
Property of French, Johnston, Lombardo &Tefertiller, not to be copied without permission 1
Functional Electrical
Stimulation Programs forPeople with SCIClinician and the Consumer Perspectives
for Clinic and Home
Moderator: Jennifer French, MBA, Neurotech Network
Speakers:
!Therese E. Johnston, PT, PhD, MBA, Jefferson School of Health Professions!Candy Tefertiller, PT, DPT, ATP, NCS, Craig Hospital!Lisa Lombardo, PT, MPT, Cleveland FES Center
APTA Combined Sections Meeting 2013
San Diego, CAJanuary 22, 2013, 8:00-10:00am
Course Objectives1. Discuss the current evidence for the use of FES for people with SCI2. Discuss FES parameter applications and modifications to achieve
optimal outcomes in individuals with neurologic disabilities
3. Discuss the opportunities and challenges of implementing FES in theclinical setting.
4. Understand multiple uses of FES from the perspectives of theconsumer and clinician.
5. Assess practical applications for successful implementation in theclinic and the home environment for FES
6. Discuss lower cost alternatives to commercially available FEStechnologies and the financial implications of FES programs andtechnologies
7. Explore current technology surrounding implantable FES systemsand current functional applications for implantable FES systems
Introductions Parameters and Evidence for Common FES
Applications: Therese Johnston
Implementing a Clinical Program for FES:Candy Tefertiller
Short Session Break Implantable FES Systems: Lisa Lombardo Consumer & Clinical Perspectives: Panel
Question & Answer
Course Agenda Priorities of Individuals with SCI
Anderson, K.D. (2004) J. Neurotrauma, 21: 1371-1383.
FES Parameters and
Evidence for FES in SCI
Therese E. Johnston, PT, PhD, MBA
Thomas Jefferson University
Philadelphia, PA
Parameters used in Clinical FES
Important to understand parameters To understand how units differ To make best decisions for the intervention
Read the booklets that come with theequipment!
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Functional Electrical Stimulation Programs
for People with SCI: Clinician and Consumer
Perspectives for Clinic and Home
January 22, 2013
Property of French, Johnston, Lombardo &Tefertiller, not to be copied without permission 2
Current (I)
Rateof movementof charged particlesin a conductor
Involves transfer ofenergythat causesphysiologicalchange
Directly related tothe voltage
Measured in amperes Our applications:milliamps (mA)
On e-stim machines,often is the intensitydial
Resistance
Defines the ease ofmovement withinthe conductor
Measured in Ohms
Ohms LawI = V/RV = I x R
Therefore, as Rincreases, V needs toincrease to maintain aconstant I
Resistance in our Applications
Use of gels, sponges, & wet gauzedecrease the resistance
Lotions, oils, dry skin, & callus increaseresistance
Alternating Current
Uninterrupted bi-directional flow ofparticles
Polarity reverses aselectrons move in
one direction & then
reverse
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Pulsed Current
Each pulse is anisolated electrical
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Biphasic Pulsed Current
Pulse & Pulse duration
Pulse= isolatedelectrical event
Can be uni or bi-directional
Pulse duration= timeto complete onepulse
Our applications:usually inmicroseconds (sec)
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Pulse duration
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Functional Electrical Stimulation Programs
for People with SCI: Clinician and Consumer
Perspectives for Clinic and Home
January 22, 2013
Property of French, Johnston, Lombardo &Tefertiller, not to be copied without permission 3
Other Terms
*Interpulseinterval= timebetweenpulses
*Period=pulse duration+ interpulseintervalduration
Interpulse
interval
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Period
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*Frequency
The number of pulses each second Important in fatigue
1 sec-
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0
This would represent 3 pulses per second (pps)
*Balance of Charge
A waveform isbalanced
when:
The area
under the
negative
phase = the
area under the
positive phase
Balanced
Unbalanced
This unbalanced waveform gives you a
net positive charge for the pulse
Amplitude Characteristics
Peak Amplitude Peak to peak amp RMS amp: takes the
shape of waveforminto account. Isabout 70% of peakamp for a truesinusoidal wave
Peak amp
Peak to
peak amp
*Ramp Up & Ramp Down Times
Ramp Up: Timeacrosssuccessivepulses to reach
peak amplitude(usually inseconds)
Ramp Down:Returning tobaseline
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Clinical Stimulators
Primary Parameters Pulse duration: usually less than 400 secAmplitude: up to 100 mA Frequency: up to 100 pps
These 3 parameters together are allimportant in how strong the electrical
stimulus is & what effects it can create
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Functional Electrical Stimulation Programs
for People with SCI: Clinician and Consumer
Perspectives for Clinic and Home
January 22, 2013
Property of French, Johnston, Lombardo &Tefertiller, not to be copied without permission 4
Effects of Increasing
Parameters
Amplitude Increases force production Pulse Duration
Increases force production (& pain over 400sec) Frequency
Increases firing rate Increases force Increases fatigue
FES Applications
This talk will include Walking Cycling
FES as a Dorsiflexion Assist during
Gait
Electrodes are typicallyplaced on the anterior
tibialis and the peroneal
nerve
Triggered by a footswitch or external
trigger
Considered an orthoticsubstitute
(Diagram: Robinson, Snyder-Mackler pg 178)
Parameters from the Literature
Pulse duration: 200-400 sec
Frequency: To obtain tetany
Amplitude: To create a 3- to 3+/5
On/off time: Times with persons gait Need a control source
Possible Stimulators
Portable stimulator that can use a trigger Foot/heel switch Hand trigger
Single application devices on the market WalkAid Bioness Odstock (UK only)
Portable Stimulator
Programmableparameters
Pre-set Custom allows wide range
Remote heel switch
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Functional Electrical Stimulation Programs
for People with SCI: Clinician and Consumer
Perspectives for Clinic and Home
January 22, 2013
Property of French, Johnston, Lombardo &Tefertiller, not to be copied without permission 5
WalkAid
One-channel stimulator Uses a Tilt or Heel Sensor
to control stimulation
Parameters 25-300 !sec 16.7- 33 pps Up to 200 mA Up to 3 sec on time (for
exercise)
Bioness L300
Gait Sensor In shoe and attachedto shoe
Detects speed &surface changes
Parameters 200 !sec 30 pps 30-35 mA
Parastep Walking System
Muscles stimulated by surface stim quadriceps, peroneal reflex for
stepping, and the gluteal muscles
Parameters: 24Hz, pulse width 150!sec, & intensity up to 300mA
The user can chose from sit/stand, stand/sit, right step & left
step, and can increase or decreasethe stim intensity while walking
Parastep, Sigmedics, Fairborn, OH
Evidence for Walking with FES
Parastep
Series of 5 papers from Miami Projectpublished on its effects (1997, Arch Phys Med Rehabil)
16 subjects, trained 32 sessions Outcomes
"walking distance, standing duration, & pace "thigh and calf girth
No change in BMD !self-concept and "depression !blood flow "time to fatigue, "workload, "VO2 during UE
ergometry
Papers by Guest et al., Jacobs et al., Klose et al., Nash et al, Needham-Shropshire et a
FES: Incomplete SCI
Field-Fote et al. 2011 FES to peroneal nerve "walking speed & distance across groups (FES/OG,
TM/manual A, TM/FES, TM/robotics)
Distance "greatest in OG group who used FES Ladouceur et al. 2000
FES for peroneal nerve (swing) & quadriceps (stance) With FES, saw
"functional mobility "maximal overground walking speed
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Functional Electrical Stimulation Programs
for People with SCI: Clinician and Consumer
Perspectives for Clinic and Home
January 22, 2013
Property of French, Johnston, Lombardo &Tefertiller, not to be copied without permission 6
FES: Incomplete SCI
Kim et al. 2004 FES: surface peroneal nerve stimulator Results: Gait speed best with FES/hinged AFO
combo, Best foot clearance with FES
Postans et al. 2004Acute SCI: FES to many muscles on TM Greater "in overground walking distance after
FES and TM training
No difference in walking speed gains
FES Cycling
Parameters of FES Cycles
Ergys 0-140 mA; 400-1000 !sec; 30, 40, 50, 60 pps
RT300 0-140mA, 100-1000 !sec, 10-100 pps
Motomed/Hasomed 0-126 mA, 20-500 !sec, up to 180 pps (using
doublets)
Common Intervention Times
From the literature Most studies have subjects cycle for 30 mins
3x/week
More recent studies have made changes tothis
Some increased duration to 1 hour Some increased frequency to 5x/week
In practice See 30-60 minutes 3-5x/week
Evidence for FES Cycling
Bone Lauer et al. 2011 (peds): hip BMD !more than in kids
without SCI
Lai et al. 2010 (acute): "loss of bone in distal femur Bloomfield et al., 1996: Bone !only if cycling at >18W Chen et al. 2005: "in distal femur, proximal tibia Frotzler et al. 2008 (higher intensity): "in trabecular
& total BMD and CSA in distal femoral epiphysis
Evidence for FES Cycling
Muscle Demchak et al. 2005 (acute): less muscle loss Johnston et al., 2011 (peds): !quadriceps
volume & stimulated strength
Scremin et al. 1999 (chronic): !CSA ofquadriceps, adductor magnus,!muscle to
adipose ratio
Duffell et al. 2008 (chronic): !stimulatedquadriceps torque,!quadriceps fatigue
resistance
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Functional Electrical Stimulation Programs
for People with SCI: Clinician and Consumer
Perspectives for Clinic and Home
January 22, 2013
Property of French, Johnston, Lombardo &Tefertiller, not to be copied without permission 7
Evidence for FES Cycling
Cardiorespiratory Hettinga, et al., 2008 (review): average VO2increase of 1.05L/min (n=264) while cycling
Johnston et al., 2011 (peds): "greater than kidswith typical development
Janssen et al., 2008 (chronic): Modified FES: !VO2, HR, cardiac output, blood lactate
Zgobar et al., 2008 (chronic): !small arterycompliance
Berry et al., 2008 (chronic): !peak power output,!peak VO2
Conclusions
Understand parameters needed andrationale for decision making Some evidence exists for the use of FES
applications in SCI
Implementing a Clinical Program
of
Functional Electrical Stimulation
Candy Tefertiller, PT, DPT, ATP, NCS
Director of Physical Therapy at Craig Hospital
Intensive Activity Based Therapy
Focus on recovery vs. compensation Retraining the neuromuscular system below
the LOI for task execution
Development and implementation of newtechnologies and interventions to facilitate
repetition and task specificity
Improvement in neuromuscular function seeneven years after neurologic injury
Electrical Stimulation and FES may offer animportant avenue to facilitate movement in aninjured musculoskeletal system and facilitateimproved function via.
**Neuroplasticity
and/or
**Improved Compensation
FES Research
Daly 2011: !gait coordination; effects X 6 months Kesar 2011: !AGRF, trailing limb angle, knee flexion (swing) Kesar 2010: !muscle performance with VFTs vs. CFTs Forssberg et al. 1977: phase dependent modulation Fung et al 1994: !H-Reflex Perez et al 2003: "spasticity Bajd et al 1997: !vertical swing Barbeau et al 2002: Therapeutic Effect Field-Fote et al 2005, 2011 (RCTs): !OG speed Thompson 2012: SCI !CST activity with 30 min PNS
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Functional Electrical Stimulation Programs
for People with SCI: Clinician and Consumer
Perspectives for Clinic and Home
January 22, 2013
Property of French, Johnston, Lombardo &Tefertiller, not to be copied without permission 8
FES in the Clinic/Home
Available Technologies: Foot Drop Systems
Bioness L300 Walkaide
Foot/Thigh Control Bioness L300 Plus
FES Cycles Restorative Therapies (UE and LE cycles) Motomed (UE and LE cycles) Ergys
FES Elliptical Restorative Therapies
FES Cycling Classes:
Inpatient and WellnessClasses 4-5 clients/hour 1PT; 1 Tech; 1-2
Volunteers
Creates competitiveand motivatingenvironment
Peer Support Transition to upright
posture whenappropriate
ABT Program: Cycling#Elliptical
Evaluate:SpasticityIsolated MovementTrunk ControlTransition:FES Bike#RT600
Neuroprosthetics
Nerve stimulation devices designed to replace or improve
function of an impaired nervous system
Commercially available for home and clinical use
FES in the Clinic:
Combined with OG training Common Peroneal/TA Gastroc/soleus Hip flexors/extensors Trunk extensors Knee flexors/extensors Foot sensors reversed to control stance vs. swing phase Strength training (TA vs. Gastroc/soleus) for clonic activity Initiate stepping prior voluntary initiation
Combined with developmental sequencing Combined with manually assisted BWS LTing
FES in the Clinic
Developmental Sequencing Over ground training Core Strengthening
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Functional Electrical Stimulation Programs
for People with SCI: Clinician and Consumer
Perspectives for Clinic and Home
January 22, 2013
Property of French, Johnston, Lombardo &Tefertiller, not to be copied without permission 9
FES in
the Clinic
FESNo FES
Step withoutassist and no
Clonus in stance
StepWithout assist
StepRequires assist
FES
>1 on anySynergy patterns
Or >2 on MA
!1 on all 3Synergy patterns
Or !2 on MA
Over GroundTraining
Manual TreadmillTraining
AssessOver Ground
Manual Treadmill
SpasticitySCATS or MA
unilateral
Step RequiresAssist and/or
Clonus in stance
FES
SpasticitySCATS or MA
unilateral
FES Training Algorithm
1. Assess unilaterally for all tasks2. As patient continues to progress,
discharge FES unilaterally whenstandard is met.
AIS C and D, BI orCVA
FESNo FES
>1 on anySynergy pattern
Or >2 on MA
!1 on all 3Synergy patterns
Or !2 on MA
FES and Locomotor Training
Easily combined Manual Assist Over ground
Reduces staff fatigue May reduce clonic activity May allow training at higher speeds including
running Spinal Cord Assessment Tool for Spasticity
(SCATS) Modified Ashworth
Conclusion
Clinical Decision Making is the Key Lots of wonderful new technology in rehab to
enhance our treatment plans
They are simply the Tools.. we need todetermine when, how and with whom to improvelong term outcomes
No one modality will work for everyone Use EBM to guide clinical decision making
Lisa Lombardo, MPTCleveland FES Center
Implantable FES Systems
Applications of FES for SCI
Learning Objectives
Discuss implanted FES research applicationsfor spinal cord injury
Provide benefits and limitations for each ofthe applications
Discuss recommendations for the future
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Functional Electrical Stimulation Programs
for People with SCI: Clinician and Consumer
Perspectives for Clinic and Home
January 22, 2013
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Cleveland FES CenterAdvancing Technology, Enhancing Life
Developing technology that improves the quality of life
of individuals with disabilities through the use ofFunctional Electrical Stimulation and enabling the
transfer of the technology into clinical deployment.
Functional Electrical Stimulation (FES) is the application of
electrical stimulation to restore function. FES can be applied
for therapeutic purposes or for replacement of lost function.
Neural Prosthesis:A device that connects directly with
the nervous system and uses FES to replace or
supplement function.
www.FEScenter.org
Email: [email protected]
Enabling technology
Implanted Stimulator-Telemeter (IST)Pacemaker for thebody
12 - 16 stimulus channels up to 2 biosignal
sensing (EMG) channels
Intramuscular electrode Multicontact spiral cuffs Universal External
Control Unit (UECU)
Clinical Applications for SCI
Trunk Control & Posture Pressure Sore Prevention Wheelchair Propulsion
Standing Transfers Balance
Stepping
Inclusion C6-T12 SCI > 6 months post-injury Intact lower motor neurons Absence of psychiatric
problems
No untreated orthopaedicproblems
No acute medical problems Adequate social support Willingness to comply w/ follow-
up procedures
Exclusion Pacemaker Cardiac arrythmia Pregnancy Contractures Seizure disorder Obesity Untreated substance
abuse
Immunodeficiency Frequent UTIs Pressure sores
FES Lower Extremity Research
Trunk Control & PosturePressure Sore Prevention Trunk Control & Posture
Wheelchair Propulsion
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Functional Electrical Stimulation Programs
for People with SCI: Clinician and Consumer
Perspectives for Clinic and Home
January 22, 2013
Property of French, Johnston, Lombardo &Tefertiller, not to be copied without permission 11
Standing SystemTransfer & Balance
Stepping System
Lower Extremity FES Summary
Controlling posture and balance may be feasible andclinically relevant
Implanted systems for standing after SCI areclinically viable
Nerve cuffs can improve system performance Standing balance can be addressed in new ways FES with EMG control can enhance walking ability
after incomplete SCI
Cleveland FES Center Programs
Spinal Cord Injury
Hand Grasp Arm & Shoulder Movement Pressure Sore Prevention Trunk Control & Posture Restoration of Cough Urology/Pelvic Health Pain & Spasticity Standing & Transfer Walking
Stroke
Shoulder Pain Reduction Pain & Spasticity Mental Image/Upper Body Hand, Implanted System Hand, Functional Control Foot Drop Walking Stability Swallowing Assistance
Acknowledgements
ALL RESEARCH VOLUNTEERS & THEIR FAMILIES
Website: www.fescenter.org
Department of Veterans Affairs; Rehabilitation Research and Development Service
National Institutes of Health: National Institute on Child Health and Human Development,National Center for Medical Rehab ilitation Research, National Institute of Neurological Disorders
and Stroke, National Institute of Biomedical Imaging and BioEngineering, National Institute ofDiabetes and Digestive and Kidney Diseases, National Institute on Deafness and OtherCommunication Disorders, National Institute on Disability and Rehabilitation Re search
U.S. Department of Education
State of Ohio: Third Frontier Program
Department of Defense: Army, Telemedicine and Advanced Technology Research Center (TATRC)
Craig H. Neilsen Foundation, Davis Phinney Fo undation, Lincy Foundation, MedtronicFoundation, Michael J. Fox Foundation, NDI Medical Inc, Case Western Reserve University,
Cleveland Clinic Foundation, Paralyzed Veterans of America, SPR Therapeutics,ThomasJefferson University, Wallace H. Coulter Foundation, Wiegand Family Foundation
Consumer & Clinician
Perspectives
Panel Question & Answer
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Functional Electrical Stimulation Programs
for People with SCI: Clinician and Consumer
Perspectives for Clinic and Home
January 22, 2013
Property of French, Johnston, Lombardo &Tefertiller, not to be copied without permission 12
Considerations to Participating in any
FES program
Not all programs are appropriate for all populations Implanted vs. external Commitments of self, family/caregiver
Time Out of pocket cost and/or reimbursement
Potentially dangerous if not used properly use Peripheral nerve damage or skin damage Infections Over-stress or fatigue the stimulated muscles
Resources to Learn More
for you and your clients
Electrotherapeutic Terminology in Physical Therapy: APTA Sectionon Clinical Electrophysiology. Published in 2000. Available through
the APTA on line store
International Functional Electrical Stimulation Society EducationSection. Website: http://www.ifess.org/cedu_consumereducation
Neurotech Network Spinal Cord Injury Fact Sheet. Website:http://www.neurotechnetwork.org/educate_spinal_cord_injury.htm
Also available on Spinal Cord Central: http://www.spinalcord.org Cleveland FES Center: http://www.fescenter.org
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