Tara Jo Manal PT, OCS, SCS: Director of Clinical Services Orthopedic Residency Director
108
Slide 1 Electrical Stimulation to Electrical Stimulation to Augment Muscle Strengthening: Augment Muscle Strengthening: Guidelines for Surgical Guidelines for Surgical Procedures, Diagnosis and Co- Procedures, Diagnosis and Co- Morbidities Morbidities Tara Jo Manal PT, OCS, SCS: Tara Jo Manal PT, OCS, SCS: Director of Clinical Services Director of Clinical Services Orthopedic Residency Director Orthopedic Residency Director University of Delaware Physical University of Delaware Physical Therapy Department Therapy Department [email protected] [email protected] 302-831-8893 302-831-8893
description
Electrical Stimulation to Augment Muscle Strengthening: Guidelines for Surgical Procedures, Diagnosis and Co-Morbidities. Tara Jo Manal PT, OCS, SCS: Director of Clinical Services Orthopedic Residency Director University of Delaware Physical Therapy Department [email protected] 302-831-8893. - PowerPoint PPT Presentation
Transcript of Tara Jo Manal PT, OCS, SCS: Director of Clinical Services Orthopedic Residency Director
EVIDENCE BASED PRACTICE FOR THE USE OF ELECTRICAL STIMULATION FOR
PAIN CONTROL AND STRENGTHING IN PHYSICAL THERAPY Tara Jo Manal PT,
OCS, SCS:
Director of Clinical Services
University of Delaware
Voltage
Voltage represents the driving force that repels like charges and attracts opposite charges
Current
Current is the movement of charged particles in response to voltage
Ampere represents an amount of charge moving per unit time
The higher the voltage, the higher the current
Slide *
Conductance
Relative ease of movement of charged particles in a charged medium
If the ease of movement is high, the resistance to movement is low
Resistance
Lower resistance provides greater comfort/tolerance by patient for higher intensity stimulation since less charge is needed to penetrate the skin
Slide *
I = V/R
Current increases as the driving force (V) is increased or as the Resistance (R) to movement is decreased
As the skin resistance decreases, more of the current can flow, increasing the response
Slide *
Properties
Impedance
Higher frequency stimulation can pass with greater ease
Impedance is the best word to describe resistance to flow in human tissue since it is comprised of the tissue resistance and the insulator (subcutaneous fat) effects of tissue
Greater the impedance, greater the intensity required to achieve therapeutic goal
High frequency stimulation is more comfortable because impedance is lower
Slide *
At fixed voltage
smaller the electrode the greater the intensity of the stimulation compared to larger electrode
Caution in setting intensity level with smaller electrodes or damaged electrodes
Very high current density can be related to biological damage or burns
Large electrodes
Slide *
Train
a continuous, repetitive series of pulses at a fixed frequency
Slide *
Slide *
Pulse duration is 1/f
To increase pulse duration to improve muscle force output you would decrease the train frequency
2000Hz = 1/2000 or 500second pulse duration
1000Hz = 1/1000 or 1000second (1 millisecond) pulse duration
Slide *
The duration is 1/5 or 20milliseconds
Slide *
Improves the muscle contraction
Slide *
Drive the motor units more quickly (Rate coding)
The main goal of using NMES is as an intervention to specifically get the muscle to contract. The quantity of this contraction is determined by the amount of force generated by the muscle.
There are 2 primary means of maximizing the force generated
1 - Increasing recruitment by activating more motor units
2 - Increase the rate at which the impulses are delivered. This will cause summation and help to achieve tetany.
Slide *
Increase recruitment via
Increase amplitude
Or BOTH
Phase Charge
Mixed Nerve
When considering how to increase recruitment phase charge comes into play which will allow for the chance of getting more motor units stimulated. Recruitment of motor units can be increased by increasing the phase charge (area under the curve).
Phase charge can be increased by either increasing the amplitude or the intensity that the electrical stimulation is delivered or increasing the pulse duration.
Certainly, combining the 2 would also result in greater increase in recruitment.
Slide *
Frequency
Increasing frequency
Tetanic contraction
Force production reaches a plateau maximum between 50-80 pulses per second
For muscle strengthening you want 50-80 pulses/second or 50-80 bursts/second
Slide *
Usually labeled “Rate or Pulse Rate”
Set the number of pulses (or AC cycles) delivered through each channel per second
As frequency is increased, impedance is decreased
Slide *
Rate Coding
Increase the frequency of stimulation
But… increased frequency increased fatigue
One way of increasing force production is by increasing recruitment and another way is by increasing frequency the stimulation is delivered.
This is an actual tracing of the force generated at different frequencies. The intensity of the stimulation was kept constant. As you will see a single twitch generates approx 100 N and as the frequency alone increases, the force generated also increases. There is however a limit to the maximum amount of force that can be produced.
Slide *
This slide illustrates this ceiling effect.
In order to get a strong tetanic contraction which is the goal of NMES, the frequency needs to be 50-80 pulses per second. Beyond the 80 pps your force gains are not as great.
In addition to frequency of 50-80 pps to achieve a strong tetanic contraction pulse duration 200-600 microsec. Pulse amplitude to achieve >50%.
Slide *
AC: generally have a maximum of 100 – 200mA
Independent vs. Shared amplitude control for multiple channels
Waveform Selection: Use evidence based decision making on the choice, most comfortable may not be the appropriate choice
Balance Control: A balance control allows for higher intensity on one channel and lower intensity on the other channel. Can be a problem in the desired intensity is achieved on one channel but not the other
Slide *
Rest time dependent on goal of treatment
Strengthening- Adequate rest to avoid fatigue
Ramp Controls: various names – slope time, surge time, ramp up, or simply ramp
Slide *
Controls the rate the amplitude increases
Provide for more comfortable onset and cessation of stimulus when very high levels of stimulation are required
Can adjust if contraction is coming on too quickly or stopping too quickly
Slide *
Ramp time
Now let’s look at what can be changed or manipulated within the machine to improve tolerance. Specifically we want to look at [read slide]
Keep in mind that how you manipulate these parameters may vary machine to machine
Slide *
Found on various stimulation devices, mostly
Can be limiting, if user is unable to program stimulation patterns for a specific application
Output Channel Selection
it is called the EMPI 300PV
Slide *
Maximal tolerable current and device dependent- MVIC above blue line
Slide *
Slide *
Proper storage
Improves conductivity
The proper storage of electrodes will maximize the effective lifespan of the electrodes. Electrodes have a defined amount of treatments that they are good for and this amount of time will differ between brands. By practicing consistent attention to proper storage techniques you will be able to keep the electrodes in play longer. The goal is to improve conductivity. This can be done by maintaining moisture. Moisture can be added by applying water either prior to their use or after their use. This can also be done by storing them correctly on the plastic. [explain slide]
Slide *
With another brand electrode and the same placement
Note the difference in the force output at a greater intensity
Slide *
With another brand electrode and the same placement
Note the difference in the force output at a greater intensity
Slide *
Electrodes
Slide *
Slide *
Slide *
Slide *
Monitor
Blunter
(Delitto et al PT 1992)
It is sometimes a challenge to get the patients to tolerate the intensity of electrical stimulation we are presenting. This stimulation is not comfortable and it requires therapists to know their patient’s coping strategies as well as motivational factors.
In cases in which a patient is having difficulty achieving the minimum intensity of NMES to have an effective treatment. Our therapists will call over a Senior therapist to basically talk with the patient and distract them, and will adjust parameters if needed.
Slide *
Explain to the patient the value of the modality
Another means to attempt to increase tolerance is to afford the patient the opportunity to feel more in control of what is happening.
This can be accomplished by [read slide]
Slide *
General
Specific
Only if you see them fatiguing drastically
Typically we start with trying to determine what exactly is the source of the patient’s limitation
comfort, don’t like the feeling, don’t like how quickly it comes on, etc
We can look from a general sense
As well as specifically
Slide *
Evidence to support the clinical use of electrical stimulation for muscle strengthening
To provide quality physical therapy intervention we make the effort to base our decision making on evidence based practice
In the use of electrical stimulation you there is an exhaustive list of research throughout the last three decades.
Slide *
Increased Functional Load
For muscle to hypertrophy and/or gain strength the overload principle of high weight at low repetitions is necessary
Currier and Mann
Looked at healthy male college students
Utilized an intensity of at least 60% MVIC paralleling voluntary exercise protocols for functional overload
Conclusion: NMES and volitional exercise were equivalent training stimuli
(Delitto,Snyder-Mackler, 1990)
Clinical relevance: These were healthy subjects with no strength deficits
Slide *
Intensity was 10-30% greater than MVC
Strength gains of 30-40%
(Delitto,Snyder-Mackler, 1990)
Clinical Relevance: Intensity on healthy subjects needed to be excessively high, and was extremely uncomfortable
Slide *
Increased Functional Load
Conclusions on Overload
Significant strength gains can be achieved in healthy muscle with an electrically augmented training program
The intensity however needs to be extremely high (>100%MVIC)
Electrical stimulation offers equivalent muscle strengthening effects to voluntary exercise in healthy subjects
If intensity level parallels volitional exercise intensities
(Delitto,Snyder-Mackler, 1990)
Intensity for NMES was from 33% - 91% MVIC, whereas it was 78% to 119% for volitional exercise
studies of NMES have strength gains from intensities as low as 25%
studies of volitional exercise do not show gains with training intensities as low as 50%
In other types of subjects, NMES is more effective
Slide *
Lower loads may still help in muscle recovering from injury/surgery
Most studies using subjects other than healthy male college students demonstrated greater strength gains in subjects training with NMES compared to volitional exercise alone
(Delitto,Snyder-Mackler, 1990)
Electrical Stimulation for Strength
Snyder-Mackler et al., 1991
Purpose: To ascertain the effects of electrically elicited co-contraction of the thigh muscles on several parameters of gait and on isokinetic performance of muscles in patients who had reconstruction of the ACL
2 groups: NMES + volitional exercise
Volitional exercise only
Slide *
Results:
Significantly greater average and peak torque of the quadriceps femoris at both 90°/sec and 120°/sec in the NMES group
No significant difference in performance of the hamstring muscles between groups
Torque produced in the involved hamstrings averaged 80% of the strength in the uninvolved leg
Clinical Relevance: Strength gains in the early postoperative phase can be significantly improved with the use of electrical stimulation
Slide *
Conclusions:
The quadriceps muscles of these patients were stronger in the eighth post-operative week than reported averages for similar patients even years after surgery
Slide *
Electrical Stimulation for Strength
Snyder-Mackler et al., 1995
Purpose: To assess the effectiveness of common regimens of electrical stimulation as an adjunct to ongoing intensive rehabilitation in the early postoperative phase after reconstructions of the anterior cruciate ligament
Slide *
High level volitional exercise
Combined high & low intensity NMES + volitional exercise
Slide *
2500Hz triangular AC current
Burst rate of 75bps
Amplitude to maximal tolerance
Frequency of 55pps
15 minutes 4 times/day
Intensity was maximum effort for 8 seconds
Visual Feedback provided
All groups followed a standard volitional exercise protocol beyond the experimental treatment interventions
Slide *
Electrical Stimulation for Strength
Snyder-Mackler et al., 1995
At least 70% recovery of the quadriceps by 6 weeks after the operation, vs. 51% in the groups that did not include high intensity stimulation
High intensity electrical stimulation leads to more normal excursions of the knee joint during stance
-at heel strike and sustain this position after heel strike
Slide *
Conclusion: For quadriceps weakness, high-level NMES with volitional exercise is more successful than volitional exercise alone
Electrical Stimulation for Strength
Fitzgerald et. al., 2003
Subjects receiving the modified NMES treatment combined with exercise demonstrated greater quadriceps strength and higher ADLS scores than the comparison group
Unfortunately, the use of a force dynamometer is not always available to us or it is too time consuming to change the unit from 1 body part to another, and for many clinicians they may not have one at their access. Therefore, to assess MVIC’s and assure we are achieving 50% or greater dose is not always feasible.
This does not stop us from attempting to utilize this adjunct intervention in the care of our patients. A recent study by Fitzgerald and colleagues provides evidence in the effectiveness in performing a modified NMES protocol to the quadriceps in patients who have undergone ACL reconstruction. The amplitude of the stimulus was set to an intensity that was high enough to produce a full tetanic contraction of the quadriceps (no fasciculations observed on visual inspection) with visual and/or palpable evidence of superior glide of the patella. Then the stimulus intensity was increased further to maximum subject tolerance. Their results comparing a NMES + exercise group to an exercise only group concluded ….
Slide *
Fitzgerald et. al., 2003
Their data support the modified NMES protocol in clinics without access to a dynamometer
Option of using a dynamometer
Authors choose the high intensity NMES protocol
It is important to note their strength gains were not as great as those seen in Snyder-Mackler et al. 1995 study, however their results do demonstrate that some stim is better than none.
The authors concede that if….
Slide *
Haug et al., 1988
Purpose: Efficacy of NMES of the quadriceps femoris during CPM following total knee arthroplasty
CPM/NMES group
Pulse width: 300 microseconds
Frequency: 35pps
On 15sec off 20 seconds at 40° setting and 65sec at 90° setting
Ramp time: 2 seconds up and 1 second down
CPM group
Haug et al., 1988
Results: Stimulation group had significant reduction of extension lag, and spent fewer days in the hospital
Intensity level was low compared to the other studies mentioned
Conclusion: Electrical stimulation combined with CPM in the treatment of patients with total knee arthroplasty is a worthwhile adjunctive therapy
The low intensity of the stimulation still lead to positive gains, which may support the idea of a window of opportunity for the greatest strength gains.
Slide *
Role of Strength in Physical Therapy Management
Strength losses can result in loss of the ability to perform activities of daily living
Strength recovery following surgery is often incomplete
Strength deficits can place patients at risk of further injury
(Snyder-Mackler, 1991)
Strength also plays a significant role in our care for our patients.
It has been reported that Strength recovery from arthroscopic to total knee replacements are often incomplete
Patients deficits can create significant disabilities such as inability to travel between floors of their home more than once a day, or ambulate the long distances required in many of the major shopping centers and result in compromise to patients participation at home and the community.
These types of strength deficits can place patients at a significant risk for falls and further injury.
Slide *
<80%MVIC
At this time lets look at the indication for choosing NMES as an intervention for your patients plan of care.
The patients who will benefit from NMES are the individuals who demonstrate strength deficits …
Once the patient is over 80%, we are talking about the range of side to side differences in relatively healthy muscle
In order to make significant gains in this population, we would need to use excessively high intensities as were proposed by Kotz.
Slide *
50-75 bursts per second
Amplitude to maximal tolerance of patient
With dynamometer feedback
Minimum of 30% MVIC for TKA
50% for PFS, Patellar Subluxations
Slide *
Procedure Modified Rehabilitation
Now we are going to take a look at how we utilize NMES in various patient populations
Slide *
Single Channel two electrode placement
Below the AIIS
Minimum Intensity
Another area in which persistent weakness is an issue is in ACL reconstruction.
This position is one in which anterior translation forces on the graft are the least and relatively negligible
Slide *
Bone-Tendon-Bone Autograft
flexion position > 40°
Due to patellofemoral issues the bone-tendon-bone graft, the angle of knee flexion can be adjusted to the most comfortable angle but no less than 40 degrees.
To prevent undo stress on the graft
Slide *
Patient encouraged to increase the intensity to maximum tolerated
Dose-response curve demonstrates greater intensities lead to greater strength gains
(Snyder-Mackler et al., 1994)
Minimum of 50% should achieve 80% recovery over the course of treatment.
Slide *
Off time- sufficient for rest/recovery before next contraction 30-90 seconds
Ramp time- as needed for comfort
Dose- maximal tolerable (no less than that needed for strength gains to be seen)
Frequency 2-3 times/week until strength recovers
Average 18 visits
NMES for Quadriceps Strengthening
Following injury or surgery to the knee, quadriceps weakness can be major impairment
We utilize electrical stimulation on all patients who demonstrate quadriceps weakness of 80% involved/uninvolved ratio or less
After ROM is, quadriceps strengthening is most important.
Potential for long term problems if strength issues are not addressed and resolved.
Quadriceps weakness may or may not be accompanied by inhibition. It may be a result simply of muscle atrophy. Just weakness.
Slide *
Post Operative Modification to ACL Protocol for Other Knee Problems
PCL 30° Knee Flexion
Meniscal Excision/ Repair None
Chondroplasty None
Post surgical intervention- follow soft tissue healing 8wks to protect surgical site or 12 weeks for bony healing
Slide *
If Pain if limiting toleration – use most comfortable angle
If Range of motion is limiting toleration – use most comfortable angle
As long as modification does not risk surgical procedure
Perform with support from the referring physician
Slide *
Identify “true” maximal force generating capability
Identify presence or absence of “inhibition”
Central activation deficit
NMES is performed at the most comfortable knee joint angle
Tape is often applied for pain control
When necessary, treatments to calm irritated structures are added
Slide *
Determined by volitional contraction
Greater than 70°
Patella taped medially
As for the non-operative cases quadriceps weakness is sometimes seen in PFS
In patellofemoral syndrome the angle of knee flexion is based on area of least contact stress and will tend to be any angle greater than or equal to 40 degrees.
Taped medially to resist lateral pull.
Follow the NMES parameters
Patella taped medially
Electrodes over the proximal quadriceps/ distal pad is moved central and superior (avoiding the VMO)
The theme continues with respect to quadriceps weakness post-operatively and the use of NMES
The angle is to protect the proximal reconstruction
Follow the NMES parameters
Precautions
Proximal/Distal Realignment
Dosage is maximal tolerable rather than % MVIC
Slide *
Quad weakness decreased by 60% following surgery
Impaired ability to perform ADL’s
Increased fall risk
Wolfson et al 1995 J Gerontol A: Biol Sci Med
Stevens et al JOR 2003
Studies looking at strength deficits following TKA have shown that muscle strength can take several months (even years) to be restored.
Stevens et al evaluated strength in patients with end-stage knee OA. Their strength was evaluated 10 days before and then 26 days after surgery. They found that quad strength decreased by 60% and the central activation decreased 17%.
The profound weakness in addition to significant changes in the patient’s ability to activate the quadriceps muscle lead to considering NMES as a treatment intervention.
Slide *
Strength gains reflect intensity tolerated
Therefore …
Ultimate goal is to generate the greatest tolerable force output
Slide *
Total Joint Arthroplasty
Amplitude targeted at a minimum of 30% MVIC (Snyder-Mackler et al., 1994)
Ramp time, frequency adjusted to increase comfort and tolerance for higher intensity stimulation
Modification of pulse duration by decreasing frequency to 2000Hz or 1500Hz (inc. pulse duration from 400 to 500 or 666 microseconds)
Persistent weakness after discharge from physical therapy is a major problem in patients who undergo total knee arthroplasty. At UD we are currently in our 2nd year of research, looking at the recovery of the quadriceps post TKA
The intervention we are looking at is obviously NMES with..
30% is above the minimum threshold for generating significant gains, and in early work with these patients, we were just unable to get them to 50% consistently. Many time they would max out the machine.
Mod. Pulse duration - can lead to greater contraction response with the same level of intensity
Slide *
Weakness can lead to compensation strategies for daily activities
COMPENSATIONS MUST BE PREVENTED!!!
After ROM is, quadriceps strengthening is most important.
Potential for long term problems if strength issues are not addressed and resolved.
Quadriceps weakness may or may not be accompanied by inhibition. It may be a result simply of muscle atrophy. Just weakness.
Slide *
Can be seen as
2. Putting involved leg out in front of her
These have to be pointed out to patient and drilled into them to stop doing.
Patient won’t even know they are doing it.
Slide *
Done in all facets of life
Watch in clinic for patient to do this, they will
Slide *
Not utilizing full extension during stance phase of gait
At heel strike to mid-stance, pt must actively force knee into terminal knee extension
Patient must consciously work on avoiding this pattern
Very common compensation pattern
Slide *
Patellar baja
Quad dysplasia
Functional Use of Quadriceps
Use of quadriceps during daily activities must be relearned in order to eliminate compensation strategies.
If it gets to this point…you are in a hole!
Slide *
Composite overview of muscle performance
Functional Testing
Lack of progress with a strengthening program
Re-education in order to retain strength gains
The absolute strength of muscle is one way to assess the patients muscles, however these measures may not correlate into functional performance.
we look at their ability to squat, jump, ambulate, run, transfer to standing to give us an overview of how they are using their muscles
Then we look for compensatory patterns
seen in avoidance patterns
we try to catch early on to prevent
If you strengthen an individual and the rest of the day they are not using that muscle, because of an avoidance pattern, more than likely you will not be able to demonstrate appreciable strength gains. Imperative to break patients of these avoidance patterns
Slide *
17 y/o female soccer player 4 months s/p ACL reconstruction
Quad Index (involved/uninvolved)
Decrease in quadriceps strength originated from decreased use and compensation strategies secondary to anterior knee pain at 3 months
Slide *
Severe pain at infrapatellar tendon and medial border of patella
Compensations to avoid use of involved leg with functional activities secondary to anterior knee pain
Slide *
No quadriceps inhibition with burst superimposition test
Decreased superior migration of patella with quad set and superior patellar hypomobility
Patient also presented with patellar baja that we theorized was due to decreased resting tone of the quadriceps from avoidance of use.
Decreased superior patellar mobility
Superior patellar mobs for her patellar hypomobility and baja.
Noxious done to infrapatellar tendon and lateral quadriceps tendon. Parameters…Used on non-contractile tissues. Use small electrodes to produce higher current density
Patient had trouble tolerating noxious stim, so we had to use ice massage for pain control. Little burns.
Could not do NMES with patient because she couldn’t tolerate it.
Slide *
Quadriceps Re-education
Two 4 x 6 inch pads over distal VMO and proximal bulk of quad
Intensity = maximum contraction patient can tolerate
Used 4 x 6 inch pads to decreased the current density to where pt could tolerate it
Patient performs exercise during ON cycle
Slide *
Slide uninvolved foot out to place more demand on involved
Put ball under uninvolved foot
Unilateral
Slide *
Patient was able to do this painfree with Muscle Max
may have helped pull patella enough to reduce irritation
Done in pain free arc of 90-45 degrees for patellofemoral considerations
Slide *
6 months post-op (16 visits) QI = 51%
7 months post-op (28 visits) QI = 72%
8 months post-op (37 visits) QI = 98%
6 months post-op (16 visits) QI = 51%
between 6 and 7 month strength check, no more muscle max
At 28 visits (7 months post-op) QI = 72%
between 7 and 8 month strength check, pt began return to soccer progression
Slide *
Chart2
36391
36391
36453
36453
36516
36516
36563
36563
36599
36599
36620
36620
36817
36817
36873
36873
36971
36971
37230
37230
533
689
622
715
200
740
375
764
564
787
839
856
1062
1171
1155
1118
1100
1050
1014
901
Sheet1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Sheet3
Slide *
By 9 months...
Completed soccer season, playing majority of games over the last couple of weeks following strict minute regulations per game
Self-management
Coaching
Helped progression and kept pt happy
Slide *
Patient Position
Involved arm belted to the body with the elbow at 90° for isometric contraction
Forearm is blocked to avoid rotation during the contraction
Stepping away from the quadriceps there are other muscle groups we use NMES to improve the effectiveness of our treatment plan.
There is no dynamometer attached to the patient, however that could be an option if it is kept in an isometric position.
Slide *
Current Intensity: Maximal tolerable with visible contraction causing movement of the arm against the restraint
Once again we are using the same parameters as we use for the quadriceps, but our intensity is based on …
Good communication with your patient will help to determine if the contractions are at maximum tolerance. In this situation it is common your patient will say that its their maximum, however when you look at the muscle a solid tetanic contraction has not been achieved yet.
Its imperative for success that you continue your communication with them to achieve a visible tetanic contraction
Slide *
The patient was then setup in a chair with his arm strapped to his trunk, and a pillow folded under his arm. This minimizes movement during contraction, making it as close to isometric as possible.
A single channel is then placed on the target muscle to be treated.
Slide *
Modified surgical procedure (loop tightens under tension)
Patient prone, knee resting in >50° of flexion and ankle in full plantar flexion
Single Channel on the medial/lateral gastroc
Current Intensity
Visible tendon gliding
Another area we utilize NMES is in the rehabilitation of Achilles tendon repairs if a Modified surgical procedure is performed
extra loop that tightens under tension
reducing the risk of rupturing the repair site
Ankle is supposed to be in full plantar flexion, this picture does not show that well
The therapist must heed caution here in the early phase to protect the surgical repair. The only modification to the parameters is intensity which is increased to the point of...
Slide *
Patient prone with knee extended and ankle in resting position
Can increase to isometric against the wall
Whereas in the late phase at >10 weeks post-operatively, we are looking for actual...
Slide *
Continue treatment until patient has full active plantar flexion
At this point the repair sight has healed and the patient is returning to an increased activity level.
Once again if you have the option of using a dynamometer in an isometric mode and can set it up with ease, then the application of minimum intensity of 50%MVIC help increase the overall effectiveness of the treatment
Slide *
Pelvis strapped to the table in posterior pelvic tilt
Assess movement to active lumbar extension and tighten as necessary
Finally, the use of NMES for the lumbar spine is a common procedure in our clinic. Understanding that overloading the erector spinae muscles is a difficult task with volitional exercise, especially with deep rotators and multifidi.
The objective of this set-up is to prevent anterior pelvic tilting
Slide *
High Intensity Electrical stimulation
A single channel is placed on the right and left side of the spine
Slide *
Using the NMES parameters, we are once again …
electrode placement
For the average sized adult this technique will be isometric from the position set-up
Ex: young figure skaters however can come right off the table and isometric is achieved at the end of the motion
Slide *
Laura Schmitt PT, DPT, OCS, SCS, ATC
Airelle Hunter PT
0
200
400
600
800
1000
1200
1400
8/19/99
10/20/9912/22/99
2/7/00
3/14/00
4/4/00
10/18/0012/13/00
3/21/0112/5/01
Newtons
Director of Clinical Services
University of Delaware
Voltage
Voltage represents the driving force that repels like charges and attracts opposite charges
Current
Current is the movement of charged particles in response to voltage
Ampere represents an amount of charge moving per unit time
The higher the voltage, the higher the current
Slide *
Conductance
Relative ease of movement of charged particles in a charged medium
If the ease of movement is high, the resistance to movement is low
Resistance
Lower resistance provides greater comfort/tolerance by patient for higher intensity stimulation since less charge is needed to penetrate the skin
Slide *
I = V/R
Current increases as the driving force (V) is increased or as the Resistance (R) to movement is decreased
As the skin resistance decreases, more of the current can flow, increasing the response
Slide *
Properties
Impedance
Higher frequency stimulation can pass with greater ease
Impedance is the best word to describe resistance to flow in human tissue since it is comprised of the tissue resistance and the insulator (subcutaneous fat) effects of tissue
Greater the impedance, greater the intensity required to achieve therapeutic goal
High frequency stimulation is more comfortable because impedance is lower
Slide *
At fixed voltage
smaller the electrode the greater the intensity of the stimulation compared to larger electrode
Caution in setting intensity level with smaller electrodes or damaged electrodes
Very high current density can be related to biological damage or burns
Large electrodes
Slide *
Train
a continuous, repetitive series of pulses at a fixed frequency
Slide *
Slide *
Pulse duration is 1/f
To increase pulse duration to improve muscle force output you would decrease the train frequency
2000Hz = 1/2000 or 500second pulse duration
1000Hz = 1/1000 or 1000second (1 millisecond) pulse duration
Slide *
The duration is 1/5 or 20milliseconds
Slide *
Improves the muscle contraction
Slide *
Drive the motor units more quickly (Rate coding)
The main goal of using NMES is as an intervention to specifically get the muscle to contract. The quantity of this contraction is determined by the amount of force generated by the muscle.
There are 2 primary means of maximizing the force generated
1 - Increasing recruitment by activating more motor units
2 - Increase the rate at which the impulses are delivered. This will cause summation and help to achieve tetany.
Slide *
Increase recruitment via
Increase amplitude
Or BOTH
Phase Charge
Mixed Nerve
When considering how to increase recruitment phase charge comes into play which will allow for the chance of getting more motor units stimulated. Recruitment of motor units can be increased by increasing the phase charge (area under the curve).
Phase charge can be increased by either increasing the amplitude or the intensity that the electrical stimulation is delivered or increasing the pulse duration.
Certainly, combining the 2 would also result in greater increase in recruitment.
Slide *
Frequency
Increasing frequency
Tetanic contraction
Force production reaches a plateau maximum between 50-80 pulses per second
For muscle strengthening you want 50-80 pulses/second or 50-80 bursts/second
Slide *
Usually labeled “Rate or Pulse Rate”
Set the number of pulses (or AC cycles) delivered through each channel per second
As frequency is increased, impedance is decreased
Slide *
Rate Coding
Increase the frequency of stimulation
But… increased frequency increased fatigue
One way of increasing force production is by increasing recruitment and another way is by increasing frequency the stimulation is delivered.
This is an actual tracing of the force generated at different frequencies. The intensity of the stimulation was kept constant. As you will see a single twitch generates approx 100 N and as the frequency alone increases, the force generated also increases. There is however a limit to the maximum amount of force that can be produced.
Slide *
This slide illustrates this ceiling effect.
In order to get a strong tetanic contraction which is the goal of NMES, the frequency needs to be 50-80 pulses per second. Beyond the 80 pps your force gains are not as great.
In addition to frequency of 50-80 pps to achieve a strong tetanic contraction pulse duration 200-600 microsec. Pulse amplitude to achieve >50%.
Slide *
AC: generally have a maximum of 100 – 200mA
Independent vs. Shared amplitude control for multiple channels
Waveform Selection: Use evidence based decision making on the choice, most comfortable may not be the appropriate choice
Balance Control: A balance control allows for higher intensity on one channel and lower intensity on the other channel. Can be a problem in the desired intensity is achieved on one channel but not the other
Slide *
Rest time dependent on goal of treatment
Strengthening- Adequate rest to avoid fatigue
Ramp Controls: various names – slope time, surge time, ramp up, or simply ramp
Slide *
Controls the rate the amplitude increases
Provide for more comfortable onset and cessation of stimulus when very high levels of stimulation are required
Can adjust if contraction is coming on too quickly or stopping too quickly
Slide *
Ramp time
Now let’s look at what can be changed or manipulated within the machine to improve tolerance. Specifically we want to look at [read slide]
Keep in mind that how you manipulate these parameters may vary machine to machine
Slide *
Found on various stimulation devices, mostly
Can be limiting, if user is unable to program stimulation patterns for a specific application
Output Channel Selection
it is called the EMPI 300PV
Slide *
Maximal tolerable current and device dependent- MVIC above blue line
Slide *
Slide *
Proper storage
Improves conductivity
The proper storage of electrodes will maximize the effective lifespan of the electrodes. Electrodes have a defined amount of treatments that they are good for and this amount of time will differ between brands. By practicing consistent attention to proper storage techniques you will be able to keep the electrodes in play longer. The goal is to improve conductivity. This can be done by maintaining moisture. Moisture can be added by applying water either prior to their use or after their use. This can also be done by storing them correctly on the plastic. [explain slide]
Slide *
With another brand electrode and the same placement
Note the difference in the force output at a greater intensity
Slide *
With another brand electrode and the same placement
Note the difference in the force output at a greater intensity
Slide *
Electrodes
Slide *
Slide *
Slide *
Slide *
Monitor
Blunter
(Delitto et al PT 1992)
It is sometimes a challenge to get the patients to tolerate the intensity of electrical stimulation we are presenting. This stimulation is not comfortable and it requires therapists to know their patient’s coping strategies as well as motivational factors.
In cases in which a patient is having difficulty achieving the minimum intensity of NMES to have an effective treatment. Our therapists will call over a Senior therapist to basically talk with the patient and distract them, and will adjust parameters if needed.
Slide *
Explain to the patient the value of the modality
Another means to attempt to increase tolerance is to afford the patient the opportunity to feel more in control of what is happening.
This can be accomplished by [read slide]
Slide *
General
Specific
Only if you see them fatiguing drastically
Typically we start with trying to determine what exactly is the source of the patient’s limitation
comfort, don’t like the feeling, don’t like how quickly it comes on, etc
We can look from a general sense
As well as specifically
Slide *
Evidence to support the clinical use of electrical stimulation for muscle strengthening
To provide quality physical therapy intervention we make the effort to base our decision making on evidence based practice
In the use of electrical stimulation you there is an exhaustive list of research throughout the last three decades.
Slide *
Increased Functional Load
For muscle to hypertrophy and/or gain strength the overload principle of high weight at low repetitions is necessary
Currier and Mann
Looked at healthy male college students
Utilized an intensity of at least 60% MVIC paralleling voluntary exercise protocols for functional overload
Conclusion: NMES and volitional exercise were equivalent training stimuli
(Delitto,Snyder-Mackler, 1990)
Clinical relevance: These were healthy subjects with no strength deficits
Slide *
Intensity was 10-30% greater than MVC
Strength gains of 30-40%
(Delitto,Snyder-Mackler, 1990)
Clinical Relevance: Intensity on healthy subjects needed to be excessively high, and was extremely uncomfortable
Slide *
Increased Functional Load
Conclusions on Overload
Significant strength gains can be achieved in healthy muscle with an electrically augmented training program
The intensity however needs to be extremely high (>100%MVIC)
Electrical stimulation offers equivalent muscle strengthening effects to voluntary exercise in healthy subjects
If intensity level parallels volitional exercise intensities
(Delitto,Snyder-Mackler, 1990)
Intensity for NMES was from 33% - 91% MVIC, whereas it was 78% to 119% for volitional exercise
studies of NMES have strength gains from intensities as low as 25%
studies of volitional exercise do not show gains with training intensities as low as 50%
In other types of subjects, NMES is more effective
Slide *
Lower loads may still help in muscle recovering from injury/surgery
Most studies using subjects other than healthy male college students demonstrated greater strength gains in subjects training with NMES compared to volitional exercise alone
(Delitto,Snyder-Mackler, 1990)
Electrical Stimulation for Strength
Snyder-Mackler et al., 1991
Purpose: To ascertain the effects of electrically elicited co-contraction of the thigh muscles on several parameters of gait and on isokinetic performance of muscles in patients who had reconstruction of the ACL
2 groups: NMES + volitional exercise
Volitional exercise only
Slide *
Results:
Significantly greater average and peak torque of the quadriceps femoris at both 90°/sec and 120°/sec in the NMES group
No significant difference in performance of the hamstring muscles between groups
Torque produced in the involved hamstrings averaged 80% of the strength in the uninvolved leg
Clinical Relevance: Strength gains in the early postoperative phase can be significantly improved with the use of electrical stimulation
Slide *
Conclusions:
The quadriceps muscles of these patients were stronger in the eighth post-operative week than reported averages for similar patients even years after surgery
Slide *
Electrical Stimulation for Strength
Snyder-Mackler et al., 1995
Purpose: To assess the effectiveness of common regimens of electrical stimulation as an adjunct to ongoing intensive rehabilitation in the early postoperative phase after reconstructions of the anterior cruciate ligament
Slide *
High level volitional exercise
Combined high & low intensity NMES + volitional exercise
Slide *
2500Hz triangular AC current
Burst rate of 75bps
Amplitude to maximal tolerance
Frequency of 55pps
15 minutes 4 times/day
Intensity was maximum effort for 8 seconds
Visual Feedback provided
All groups followed a standard volitional exercise protocol beyond the experimental treatment interventions
Slide *
Electrical Stimulation for Strength
Snyder-Mackler et al., 1995
At least 70% recovery of the quadriceps by 6 weeks after the operation, vs. 51% in the groups that did not include high intensity stimulation
High intensity electrical stimulation leads to more normal excursions of the knee joint during stance
-at heel strike and sustain this position after heel strike
Slide *
Conclusion: For quadriceps weakness, high-level NMES with volitional exercise is more successful than volitional exercise alone
Electrical Stimulation for Strength
Fitzgerald et. al., 2003
Subjects receiving the modified NMES treatment combined with exercise demonstrated greater quadriceps strength and higher ADLS scores than the comparison group
Unfortunately, the use of a force dynamometer is not always available to us or it is too time consuming to change the unit from 1 body part to another, and for many clinicians they may not have one at their access. Therefore, to assess MVIC’s and assure we are achieving 50% or greater dose is not always feasible.
This does not stop us from attempting to utilize this adjunct intervention in the care of our patients. A recent study by Fitzgerald and colleagues provides evidence in the effectiveness in performing a modified NMES protocol to the quadriceps in patients who have undergone ACL reconstruction. The amplitude of the stimulus was set to an intensity that was high enough to produce a full tetanic contraction of the quadriceps (no fasciculations observed on visual inspection) with visual and/or palpable evidence of superior glide of the patella. Then the stimulus intensity was increased further to maximum subject tolerance. Their results comparing a NMES + exercise group to an exercise only group concluded ….
Slide *
Fitzgerald et. al., 2003
Their data support the modified NMES protocol in clinics without access to a dynamometer
Option of using a dynamometer
Authors choose the high intensity NMES protocol
It is important to note their strength gains were not as great as those seen in Snyder-Mackler et al. 1995 study, however their results do demonstrate that some stim is better than none.
The authors concede that if….
Slide *
Haug et al., 1988
Purpose: Efficacy of NMES of the quadriceps femoris during CPM following total knee arthroplasty
CPM/NMES group
Pulse width: 300 microseconds
Frequency: 35pps
On 15sec off 20 seconds at 40° setting and 65sec at 90° setting
Ramp time: 2 seconds up and 1 second down
CPM group
Haug et al., 1988
Results: Stimulation group had significant reduction of extension lag, and spent fewer days in the hospital
Intensity level was low compared to the other studies mentioned
Conclusion: Electrical stimulation combined with CPM in the treatment of patients with total knee arthroplasty is a worthwhile adjunctive therapy
The low intensity of the stimulation still lead to positive gains, which may support the idea of a window of opportunity for the greatest strength gains.
Slide *
Role of Strength in Physical Therapy Management
Strength losses can result in loss of the ability to perform activities of daily living
Strength recovery following surgery is often incomplete
Strength deficits can place patients at risk of further injury
(Snyder-Mackler, 1991)
Strength also plays a significant role in our care for our patients.
It has been reported that Strength recovery from arthroscopic to total knee replacements are often incomplete
Patients deficits can create significant disabilities such as inability to travel between floors of their home more than once a day, or ambulate the long distances required in many of the major shopping centers and result in compromise to patients participation at home and the community.
These types of strength deficits can place patients at a significant risk for falls and further injury.
Slide *
<80%MVIC
At this time lets look at the indication for choosing NMES as an intervention for your patients plan of care.
The patients who will benefit from NMES are the individuals who demonstrate strength deficits …
Once the patient is over 80%, we are talking about the range of side to side differences in relatively healthy muscle
In order to make significant gains in this population, we would need to use excessively high intensities as were proposed by Kotz.
Slide *
50-75 bursts per second
Amplitude to maximal tolerance of patient
With dynamometer feedback
Minimum of 30% MVIC for TKA
50% for PFS, Patellar Subluxations
Slide *
Procedure Modified Rehabilitation
Now we are going to take a look at how we utilize NMES in various patient populations
Slide *
Single Channel two electrode placement
Below the AIIS
Minimum Intensity
Another area in which persistent weakness is an issue is in ACL reconstruction.
This position is one in which anterior translation forces on the graft are the least and relatively negligible
Slide *
Bone-Tendon-Bone Autograft
flexion position > 40°
Due to patellofemoral issues the bone-tendon-bone graft, the angle of knee flexion can be adjusted to the most comfortable angle but no less than 40 degrees.
To prevent undo stress on the graft
Slide *
Patient encouraged to increase the intensity to maximum tolerated
Dose-response curve demonstrates greater intensities lead to greater strength gains
(Snyder-Mackler et al., 1994)
Minimum of 50% should achieve 80% recovery over the course of treatment.
Slide *
Off time- sufficient for rest/recovery before next contraction 30-90 seconds
Ramp time- as needed for comfort
Dose- maximal tolerable (no less than that needed for strength gains to be seen)
Frequency 2-3 times/week until strength recovers
Average 18 visits
NMES for Quadriceps Strengthening
Following injury or surgery to the knee, quadriceps weakness can be major impairment
We utilize electrical stimulation on all patients who demonstrate quadriceps weakness of 80% involved/uninvolved ratio or less
After ROM is, quadriceps strengthening is most important.
Potential for long term problems if strength issues are not addressed and resolved.
Quadriceps weakness may or may not be accompanied by inhibition. It may be a result simply of muscle atrophy. Just weakness.
Slide *
Post Operative Modification to ACL Protocol for Other Knee Problems
PCL 30° Knee Flexion
Meniscal Excision/ Repair None
Chondroplasty None
Post surgical intervention- follow soft tissue healing 8wks to protect surgical site or 12 weeks for bony healing
Slide *
If Pain if limiting toleration – use most comfortable angle
If Range of motion is limiting toleration – use most comfortable angle
As long as modification does not risk surgical procedure
Perform with support from the referring physician
Slide *
Identify “true” maximal force generating capability
Identify presence or absence of “inhibition”
Central activation deficit
NMES is performed at the most comfortable knee joint angle
Tape is often applied for pain control
When necessary, treatments to calm irritated structures are added
Slide *
Determined by volitional contraction
Greater than 70°
Patella taped medially
As for the non-operative cases quadriceps weakness is sometimes seen in PFS
In patellofemoral syndrome the angle of knee flexion is based on area of least contact stress and will tend to be any angle greater than or equal to 40 degrees.
Taped medially to resist lateral pull.
Follow the NMES parameters
Patella taped medially
Electrodes over the proximal quadriceps/ distal pad is moved central and superior (avoiding the VMO)
The theme continues with respect to quadriceps weakness post-operatively and the use of NMES
The angle is to protect the proximal reconstruction
Follow the NMES parameters
Precautions
Proximal/Distal Realignment
Dosage is maximal tolerable rather than % MVIC
Slide *
Quad weakness decreased by 60% following surgery
Impaired ability to perform ADL’s
Increased fall risk
Wolfson et al 1995 J Gerontol A: Biol Sci Med
Stevens et al JOR 2003
Studies looking at strength deficits following TKA have shown that muscle strength can take several months (even years) to be restored.
Stevens et al evaluated strength in patients with end-stage knee OA. Their strength was evaluated 10 days before and then 26 days after surgery. They found that quad strength decreased by 60% and the central activation decreased 17%.
The profound weakness in addition to significant changes in the patient’s ability to activate the quadriceps muscle lead to considering NMES as a treatment intervention.
Slide *
Strength gains reflect intensity tolerated
Therefore …
Ultimate goal is to generate the greatest tolerable force output
Slide *
Total Joint Arthroplasty
Amplitude targeted at a minimum of 30% MVIC (Snyder-Mackler et al., 1994)
Ramp time, frequency adjusted to increase comfort and tolerance for higher intensity stimulation
Modification of pulse duration by decreasing frequency to 2000Hz or 1500Hz (inc. pulse duration from 400 to 500 or 666 microseconds)
Persistent weakness after discharge from physical therapy is a major problem in patients who undergo total knee arthroplasty. At UD we are currently in our 2nd year of research, looking at the recovery of the quadriceps post TKA
The intervention we are looking at is obviously NMES with..
30% is above the minimum threshold for generating significant gains, and in early work with these patients, we were just unable to get them to 50% consistently. Many time they would max out the machine.
Mod. Pulse duration - can lead to greater contraction response with the same level of intensity
Slide *
Weakness can lead to compensation strategies for daily activities
COMPENSATIONS MUST BE PREVENTED!!!
After ROM is, quadriceps strengthening is most important.
Potential for long term problems if strength issues are not addressed and resolved.
Quadriceps weakness may or may not be accompanied by inhibition. It may be a result simply of muscle atrophy. Just weakness.
Slide *
Can be seen as
2. Putting involved leg out in front of her
These have to be pointed out to patient and drilled into them to stop doing.
Patient won’t even know they are doing it.
Slide *
Done in all facets of life
Watch in clinic for patient to do this, they will
Slide *
Not utilizing full extension during stance phase of gait
At heel strike to mid-stance, pt must actively force knee into terminal knee extension
Patient must consciously work on avoiding this pattern
Very common compensation pattern
Slide *
Patellar baja
Quad dysplasia
Functional Use of Quadriceps
Use of quadriceps during daily activities must be relearned in order to eliminate compensation strategies.
If it gets to this point…you are in a hole!
Slide *
Composite overview of muscle performance
Functional Testing
Lack of progress with a strengthening program
Re-education in order to retain strength gains
The absolute strength of muscle is one way to assess the patients muscles, however these measures may not correlate into functional performance.
we look at their ability to squat, jump, ambulate, run, transfer to standing to give us an overview of how they are using their muscles
Then we look for compensatory patterns
seen in avoidance patterns
we try to catch early on to prevent
If you strengthen an individual and the rest of the day they are not using that muscle, because of an avoidance pattern, more than likely you will not be able to demonstrate appreciable strength gains. Imperative to break patients of these avoidance patterns
Slide *
17 y/o female soccer player 4 months s/p ACL reconstruction
Quad Index (involved/uninvolved)
Decrease in quadriceps strength originated from decreased use and compensation strategies secondary to anterior knee pain at 3 months
Slide *
Severe pain at infrapatellar tendon and medial border of patella
Compensations to avoid use of involved leg with functional activities secondary to anterior knee pain
Slide *
No quadriceps inhibition with burst superimposition test
Decreased superior migration of patella with quad set and superior patellar hypomobility
Patient also presented with patellar baja that we theorized was due to decreased resting tone of the quadriceps from avoidance of use.
Decreased superior patellar mobility
Superior patellar mobs for her patellar hypomobility and baja.
Noxious done to infrapatellar tendon and lateral quadriceps tendon. Parameters…Used on non-contractile tissues. Use small electrodes to produce higher current density
Patient had trouble tolerating noxious stim, so we had to use ice massage for pain control. Little burns.
Could not do NMES with patient because she couldn’t tolerate it.
Slide *
Quadriceps Re-education
Two 4 x 6 inch pads over distal VMO and proximal bulk of quad
Intensity = maximum contraction patient can tolerate
Used 4 x 6 inch pads to decreased the current density to where pt could tolerate it
Patient performs exercise during ON cycle
Slide *
Slide uninvolved foot out to place more demand on involved
Put ball under uninvolved foot
Unilateral
Slide *
Patient was able to do this painfree with Muscle Max
may have helped pull patella enough to reduce irritation
Done in pain free arc of 90-45 degrees for patellofemoral considerations
Slide *
6 months post-op (16 visits) QI = 51%
7 months post-op (28 visits) QI = 72%
8 months post-op (37 visits) QI = 98%
6 months post-op (16 visits) QI = 51%
between 6 and 7 month strength check, no more muscle max
At 28 visits (7 months post-op) QI = 72%
between 7 and 8 month strength check, pt began return to soccer progression
Slide *
Chart2
36391
36391
36453
36453
36516
36516
36563
36563
36599
36599
36620
36620
36817
36817
36873
36873
36971
36971
37230
37230
533
689
622
715
200
740
375
764
564
787
839
856
1062
1171
1155
1118
1100
1050
1014
901
Sheet1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Sheet3
Slide *
By 9 months...
Completed soccer season, playing majority of games over the last couple of weeks following strict minute regulations per game
Self-management
Coaching
Helped progression and kept pt happy
Slide *
Patient Position
Involved arm belted to the body with the elbow at 90° for isometric contraction
Forearm is blocked to avoid rotation during the contraction
Stepping away from the quadriceps there are other muscle groups we use NMES to improve the effectiveness of our treatment plan.
There is no dynamometer attached to the patient, however that could be an option if it is kept in an isometric position.
Slide *
Current Intensity: Maximal tolerable with visible contraction causing movement of the arm against the restraint
Once again we are using the same parameters as we use for the quadriceps, but our intensity is based on …
Good communication with your patient will help to determine if the contractions are at maximum tolerance. In this situation it is common your patient will say that its their maximum, however when you look at the muscle a solid tetanic contraction has not been achieved yet.
Its imperative for success that you continue your communication with them to achieve a visible tetanic contraction
Slide *
The patient was then setup in a chair with his arm strapped to his trunk, and a pillow folded under his arm. This minimizes movement during contraction, making it as close to isometric as possible.
A single channel is then placed on the target muscle to be treated.
Slide *
Modified surgical procedure (loop tightens under tension)
Patient prone, knee resting in >50° of flexion and ankle in full plantar flexion
Single Channel on the medial/lateral gastroc
Current Intensity
Visible tendon gliding
Another area we utilize NMES is in the rehabilitation of Achilles tendon repairs if a Modified surgical procedure is performed
extra loop that tightens under tension
reducing the risk of rupturing the repair site
Ankle is supposed to be in full plantar flexion, this picture does not show that well
The therapist must heed caution here in the early phase to protect the surgical repair. The only modification to the parameters is intensity which is increased to the point of...
Slide *
Patient prone with knee extended and ankle in resting position
Can increase to isometric against the wall
Whereas in the late phase at >10 weeks post-operatively, we are looking for actual...
Slide *
Continue treatment until patient has full active plantar flexion
At this point the repair sight has healed and the patient is returning to an increased activity level.
Once again if you have the option of using a dynamometer in an isometric mode and can set it up with ease, then the application of minimum intensity of 50%MVIC help increase the overall effectiveness of the treatment
Slide *
Pelvis strapped to the table in posterior pelvic tilt
Assess movement to active lumbar extension and tighten as necessary
Finally, the use of NMES for the lumbar spine is a common procedure in our clinic. Understanding that overloading the erector spinae muscles is a difficult task with volitional exercise, especially with deep rotators and multifidi.
The objective of this set-up is to prevent anterior pelvic tilting
Slide *
High Intensity Electrical stimulation
A single channel is placed on the right and left side of the spine
Slide *
Using the NMES parameters, we are once again …
electrode placement
For the average sized adult this technique will be isometric from the position set-up
Ex: young figure skaters however can come right off the table and isometric is achieved at the end of the motion
Slide *
Laura Schmitt PT, DPT, OCS, SCS, ATC
Airelle Hunter PT
0
200
400
600
800
1000
1200
1400
8/19/99
10/20/9912/22/99
2/7/00
3/14/00
4/4/00
10/18/0012/13/00
3/21/0112/5/01
Newtons
