Download Biofeedback - Chapman University

www.yello.co.nz/site/biofeedback/ (2004)
Biofeedback
In Neuromuscular Rehabilitation
Kelsey Bains · Jennifer Byrd
Sara Nottingham · Chrissy Perez
Objectives
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Define Biofeedback and the significance of its use in the
clinical setting.
Explain electromyography and its physiologic role in the
measurement and decoding of electrical activity.
Describe the specific clinical uses of biofeedback in
injury rehabilitation.
Show the components of biofeedback machines and their
role in the treatment procedure.
Outline the setup and administration of biofeedback on a
patient.
Identify different types of biofeedback machines and
electrodes.
Express the advantages and disadvantages of
biofeedback use in rehabilitation.
What is Biofeedback?
¾ Biofeedback is a therapeutic modality that
uses electromyography to monitor the
body’
body’s electrical activity and express it in a
way that the patient can view their own
progress. 1
¾ Electrical activity enters the machine and
is expressed through visual or auditory
means that can be observed by an athlete,
bridging the mindmind-body connection. 7
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What is Biofeedback?
(Continued)
www.ashafoundation.org/whatisbiofeedback.htm (2004)
Electromyography (EMG): The
Foundation of Biofeedback
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Muscle contraction begins at the motor unit
when a depolarization threshold at a nerve is
reached and the neurotransmitter acetylcholine
(ACh)
ACh) is released. 2, 5, 6, 7
Prentice, W.E. (2003). Therapeutic Modalities: For Sports Medicine and Athletic Training. (5th ed.). New York: McGraw Hills
Electromyography (EMG): The
Foundation of Biofeedback
(Continued)
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This voltage change at depolarization is detected
by electrode pads that lead to the biofeedback
machine that decodes the signals. 8
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While the processing and display of information
is the most crucial part of biofeedback, there is
no universal procedure for quantifying
information between different manufacturers
and machines. 7
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The Measuring and Decoding
of Electrical Activity
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Electrodes placed on the skin detect both electrical and
nonnon-electrical (extraneous) activity. These signals must
be manipulated by the machine to make them visible to
the patient. 5, 6, 7
Biofeedback electrodes have two active and one reference
electrode, which is typically placed inin-between the two
active pads.
Signals from the active pads are sent to a “differential
amplifier,”
amplifier,” which separates extraneous and electrical
signals and amplifies the electrical signals. 5, 6, 7
Once the electrical signal has been separated, it becomes
a raw voltage, which is smoothed into a quantifiable
signal that can be viewed by the athlete. 5, 6, 7
The Measuring and Decoding
of Electrical Activity
Differential Amplifier
Active
“+”
Active
“-”
Referred
Electricity
Muscle
Electricity
Raw
Signal
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Smoothed &
Integrated
Displayable
Information
Depending on the type of
machine, signals are
represented with sounds,
vibrations, or visual
stimulus to the athlete. 7, 8
The Significance of EMG in
the Clinical Setting
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Electromyography detects all electrical activity, not just
muscle contraction. This is significant in the early stages
of postpost-surgical rehabilitation when visible muscle
contraction can not always be seen. 3, 4, 6
Association for Applied Psychophysiology & Biofeedback (2004)
3
The Significance of EMG in the
Clinical Setting
(Continued)
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Biofeedback is significant in
the psychological aspects of
injury rehabilitation, and can
encourage rehabilitation
efficacy. 4, 5
During ACL rehabilitation,
electrodes can be applied to
the vastus medialis oblique
while exercising so the patient
can monitor their progress
throughout the rehabilitation
process.
Feedback
Model/
Decision
Sensing
Biomechanics /
Control model
Clinical Applications of
Biofeedback
¾ There are three significant roles of
biofeedback for the use of
rehabilitation
• Muscle ReRe-education
• Relaxation of Muscle Guarding
• Pain Reduction
The Use of Biofeedback for
Muscle Re-Education
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Biofeedback assists in isolating a specific muscle and
measures its contraction individual to other muscles
(ex: when contracting the quadriceps muscle group, the
hamstrings are often subconsciously contracted.
Biofeedback can differentiate between the
contractions). 3, 7
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Muscle rere-education is performed by progressively
increasing isometric contractions that last for 66-10
seconds each by adjusting the sensitivity of the machine
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as the athlete improves.
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Biofeedback is significant in testing muscles that are not
functional enough to be evaluated in manual muscle
tests. 6
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The Use of Biofeedback for
Muscle Guarding
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Biofeedback expresses muscle activity that an
apprehensive athlete may not be able to
recognize without visual/auditory feedback. 5
A patient will gradually increase contractions as
their pain is reduced, which gives them security
in their movements and encourages them to do
more.
Increasing sensitivity and moving electrodes
further apart during a session will stimulate an
athlete to improve contractions. 6
The Use of Biofeedback for
Pain Reduction
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Biofeedback reduces pain by relaxing tense
muscles.
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Relaxation of muscles helps interrupt the painpainspasm cycle, which allows the athlete to both
increase muscle contraction and move with less
pain. 6
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Biofeedback works psychologically against pain
because visual feedback encourages progressive
relaxation. 6
The Significance of Biofeedback
in Surgery Rehabilitation
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Biofeedback is helpful in postpost-surgery rehab because it
works psychologically to establish longlong-term effects. 6
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PostPost-surgically, biofeedback initiates voluntary muscle
control, which leads to better progression through later
stages of rehabilitation. 1, 3, 5
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Specific to Anterior Cruciate Ligament (ACL)
reconstruction rehabilitation, biofeedback helps to isolate
muscles and regain control in the first 22-4 weeks. 3, 4
5
The Application of
Biofeedback
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Patient Preparation:
z The patient can be sitting, standing, or lying down
– depending on the goals of treatment.
z The Therapist facilitating the session should
demonstrate biofeedback on himself/herself first
to guide the patient. 6
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Skin Preparation:
z The area of treatment should be shaved if
necessary. 8
z The area should be scrubbed with an alcohol pad
to remove dirt, oil, and dead skin. 8
All about Electrodes
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While electrode sizes vary,
increasing the electrode size
will not amplify the electrical
signal. 6
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A conductive gel or other
medium should be applied to
the electrode to increase
signal detection. 6, 8
All about Electrodes
(Continued)
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As biofeedback machines will differ, so will electrodes.
Newer models of electrodes (shown below) contain both
active and reference electrodes on the same pad to
ensure proper application.
Active
Electrodes
+
_
Reference
electrode
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All about Electrodes
(continued)
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Electrodes should be placed parallel to the
direction of the muscle being tested, with the
reference electrode placed inin-between the active
pads. 6
All about Electrodes
(continued)
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Electrodes should surround the smallest area
possible to detect electrical activity as accurately
as possible. 6
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Electrodes should be secured to the body part
with an elastic or nonnon-conductive wrap to
minimize excess movement of the pads that will
increase extraneous signals. 6
Application of Biofeedback
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Biofeedback machines detect information according to
the designated sensitivity level set on the machine. The
lower the sensitivity level, the lower the amount of
muscle activity needed to give feedback. 8
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A patient progresses by increasing sensitivity levels as a
patient becomes stronger and more aware of his
voluntary contractions.
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The operational procedures are unique to each machine,
and should be followed accordingly throughout each
session.
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Types of Biofeedback
Machines
www3.sympatico.ca/…/physio.html (2004)
Association for Applied Psychophysiology & Biofeedback (2004)
Advantages and
Disadvantages of Biofeedback
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Voluntary psychomotor control of activity is a significant
beneficial aspect of biofeedback. 1, 3, 5
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Prentice and Voight state that “Perhaps the biggest
advantage of biofeedback is that it provides the patient
with a chance to correct small changes in performance
that are immediately noted and rewarded so that
eventually larger changes or improvement in
performance can be accomplished”
accomplished” (Page 305).
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One disadvantage of electromyographic biofeedback is
the training and guidance required by the therapist to
facilitate the first few treatment sessions. 4
Review Quiz
1) Electromyography is based on the detection of:
a) muscle contraction
b) firing of a motor neuron
c) strength of electrical stimulation placed on the body
d) sensitivity of electrodes
CORRECT: B
2) NonNon-electrical activity detected by biofeedback
electrodes is also known as:
a) active electricity
b) inactive electricity
c) extraneous activity
d) inactive signals
CORRECT: C
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Review Quiz
3) The signals manipulated and expressed to the
patient by the biofeedback machine are:
a) electrical signals
b) nonnon-electrical signals
c) raw signals
d) raw voltage
CORRECT: D
4) Biofeedback has been shown to :
a) reduce muscle guarding
b) reduce muscle pain
c) assist with muscle rere-education
d) all of the above
CORRECT: D
Review Quiz
5) Biofeedback assists in muscle rere-education in the first _____ of
ACL reconstruction postpost-surgical rehabilitation:
a) week
b) 22-4 weeks
c) 44-6 weeks
d) biofeedback should not be used in postpost-surgical
rehabilitation
CORRECT: B
6) Which of the following is NOT a necessary preparation
technique for a biofeedback session:
a) apply conductive gel to the electrodes
b) shave the treatment area if there is only a small
amount of hair
c) have the athlete lie down
d) demonstrate the procedure on yourself before
applying it to the athlete
CORRECT: C
Review Quiz
7) Which of the following is the biggest advantage of
biofeedback?
a) regaining voluntary muscle control
b) isolating muscle contraction in postpost-surgical rehabilitation
c) the athletic trainer’
trainer’s role in guidance of the athlete
d) psychological encouragement throughout rehab
e) both a & d
CORRECT: E
8) What is insignificant about electrodes when performing
biofeedback rehabilitation?
a) electrode size
b) electrode location
c) the application of a conductive gel to the pads
d) clean electrodes
CORRECT: A
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References Cited
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2.
3.
4.
5.
6.
7.
8.
Andrews, J., Harrelson, G., Wilk,
Wilk, K. (1998). Physical
rehabilitation of the injured athlete. Philadelphia: Harcourt Brace.
Donatelli,
Donatelli, R., Wooden, M. (2001). Orthopedic physical therapy
(3rd ed.). New York: Churchill Livingston.
Draper, V. (1990). Electromyograpic biofeedback and recovery of
quadriceps femoris muscle function following anterior cruciate
ligament reconstruction. Physical Therapy 70(1),
70(1), 11.
Linsay,
Linsay, K.A. (1997 Andrews, J., Harrelson, G., Wilk,
Wilk, K. (1998).
Physical).
Physical). Electromyographic biofeedback (Jennifer Stone, ed.).
Athletic Therapy Today,
Today, July, 49.
Nelson, R., Hayes, K., Currier, D. (1999). Clinical electrotherapy
(3rd ed.). Stratford: Appleton and Lange.
Prentice, W. (2003). Therapeutic modalities for sports medicine
and athletic training (5th ed.). New York: McGraw Hill.
Prentice, W., Voight,
Voight, M. (2001). Techniques in musculoskeletal
rehabilitation.
rehabilitation. New York: McGraw Hill.
Starkey, C. (1999). Therapeutic modalities (2nd ed.).
Philadelphia: F.A. Davis.
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