PT 510 - E Stim II

When do we use NMES or EMS?

When do we use NMES or EMS?

after injury such as CVA or prolonged immobilization

What is the purpose of a NMES or EMS?

e-stim to generate muscle contractions via stimulation to increase strength or re-educate muscles

Functional electrical stimulation (FES) uses NMES to elicit what?

contractions during functional movements and movement patterns

What are tetanic contractions?

when we increase the frequency of stimuli progressively fuses the individual muscle twitches to a point where individual muscle twitches are not discernible

What does the frequency have to be to generate a tetanic contraction?

33 Hz

What are the principles of innervated muscle?

• NERVES are being stimulated

• Strengthen weakened muscle

• re-educate muscles

• treat muscle spasms

• muscle pump

• SC injuries

What are the principles of denervated muscle?

• MUSCLE is being stimulated

• minimize / prevent atrophy, possible while nerves regenerate

• prevent loss of contractile strength and muscle fiber size

• prevent / limit edema and venous stasis

In regards to ES use for denervated muscles, what can be some issues that can occur?

• ES may interfere with nerve regeneration thus delaying functional return

• electrically evoked muscle contractions may disrupt the regenerating neuromuscular junction slowing re-innervation

• may traumatize denervated muscle since it is more sensitive to trauma than normal tissue

Can you substitute normal muscle innervation with ES?

NO, b/c you are stimulating the muscle directly as it’s not the same as stimulating the nerve attached to the muscle

Denervated muscle even aided with ES, can lose what?

leakage of AcH and degenerates

What is the waveform, amplitude, frequency, and pulse width for denervated muscles?

• waveform = continuous DC or pulsed DC

• amplitude = enough to cause a tetanic contraction

• frequency = at least 33 Hz

• Pulse width = must be long

Does ramp time matter with denervated muscle?

no because denervated muscles does not accommodate

Where is the location of stimulation for denervated muscles?

• a tap key will be used to facilitate easy moving of stimulation over appropriate motor points without the need to be constantly moving electrodes

• Dispersive pad should be placed somewhere distant from the treatment site

What should be the duration of treatment for denervated muscle?

3 sets of 10-20 reps daily (up to 3x a day if possible) or until motor point is fatigued

What is Bell’s Palsy?

unilateral facial paralysis caused by involvement of the facial nerve (CNVII)

What are accepted interventions for Bell’s Palsy?

• electrical stimulation with DC to muscles directly or

• AC to facial nerves

What are some issues with ES in Bell’s Palsy treatment?

• small size and proximity of the facial muscles makes it difficult to isolate and stimulate specific muscles

• application of neuromuscular retraining including electrical stimulation for facial paralysis can effectively reduce complications after facial nerve injury

• billing issues as some third party payer do not reimburse for charging for ES

What are indications for using ES on a Bell’s Palsy pt?

DC can be used to reduce atrophy and facilitate muscle strengthening to muscles that have lost their peripheral nerve supply

What are contraindications for using ES on a Bell’s Palsy pt?

same as general contraindication for normal ES

• be extra cautious of skin irritation when using this mode of ES as galvanic DC can cause skin irritation

What is the purpose of using Russian stim?

• improve motor recruitment

• facilitate muscle hypertrophy (increase strength of normal muscle)

• improve strength

What kind of current and frequency is used when using Russian stim?

• AC

• medium frequency

What is the amplitude, pulse rate, and pulse duration for Russian stim?

• amplitude = tetanic muscle contraction

• pulse rate = at least 33 Hz

• PD = 150-200 msec

Why would we higher the pulse duration in Russian stim?

if we want to decrease spasm/spasticity by fatiguing the muscle

Current can be applied to provide stimulation for strengthing during the follow volitional activities…:

• isometric exercises at various points through the range

• slow isokinetic exercise

• short arc joint movement where movement is restricted

Describe the duty cycle for exercise mode in Russian Stim.

• ramped 1-5 sec

• 10 sec on, 50 sec off

• 10-20 minutes of treatment time, or until muscle fatigues

Describe the duty cycle to decrease spasm / spasticity in Russian stim.

• ramped 1-5 sec

• 10 sec on, 10 sec off

• treatment time = until muscle fatigues

Describe the electrode placement for Russian stim.

• monopolar with small pad over muscle’s motor point and larger pad (4x larger) elsewhere

• bipolar = utilizes 2 equally seized electrode (at least one pad width apart) over muscle belly

Is it important to recognize the anode and cathode in Russian Stim? Why?

no, because each electrode plays the dual role of anode and cathode in the application

What should be considered when selecting the size of electrode in Russian Stim?

the size or surface area should resemble the size of the area that you wish to stimulate

In regards to the size of the electrode in Russian stim, the larger the current amplitude, the ___________ the stimulating surface area.

• what can happen if you choose an electrode that is too small?

• larger

• may cause pain to the pt as well as a thermal skin burn

Describe the positioning of the electrodes in Russian stim.

• the interelectrode distance influences current dispersion

  • the greater the interelectrode distance, the deeper into the tissue the current penetration

  • the close the electrode placement, the more superficial the stimulating effect

• no closer than the diameter of the smallest electrode

What is the purpose of iontophoresis?

to transfer medical agents through the skin for therapeutic purpses

• repel like ions

What kind of current does iontophoresis use?

DC

Describe the roles of the anode and cathode for iontophoresis.

• anode (+) = used to repel medications that are positively charged transdermally

• cathode (-) = used to repel medications that are negatively charged transdermally

Where is medication and saline applied to in iontophoresis?

• medication = to the side of the pad with the same charge

• saline = to the side of the pad with the opposite charge

Acetate

• (-) charge

• dissolves calcium deposits in soft tissues (i.e tendons, ligaments)

Dexamethasone

• (-) charge

• anti-inflammatory

Glucocorticoid

• (-) charge

• anti-inflammatory

Salicylate

• (-) charge

• decreases local pain and inflammation

Hydrocortisone

• (+) charge

• anti-inflammatory

Hyoluronidase

• (+) charge

• anti-inflammatory

Lidocaine

• (+) charge

• decreases local pain

Zinc

• (+) charge

• enhances tissue healing

What are indications of iontophoresis?

• decrease pain, inflammation, edema

• hyperhidrosis (excessive sweating)

• softening of cutaneous tissue

• and bactericidal

What are contraindications of iontophoresis?

• allergy or hypersensitivity to the ions used

• over scar tissue / bruises / broken skin

• impaired skin sensation

• metal in or near treatment area

What is high volt galvanic stimulation used for?

edema reduction and wound healing

What kind of current is used in HVPC?

direct but is pulsed for decreased risk of burns

Describe HVPC tissue impedance.

encounters very low impedance making it comfortable for the pt and effective

Describe the anode and cathode for edema reduction in HVPC.

• edema is negatively charged, so use a monopolar set up with the cathode pads over the swollen area to repel the fluid

• the anode dispersive pad (+) is positioned closer to the heart than the treatment site to attract edema

Describe the cathode for infected wounds in HVPC.

use the cathode (-) as active pad

What is the polarity within the inflammatory phase?

negative

What is the polarity within the proliferation phase?

positive

What are contraindications of HVPC?

• general ES contraindications

• malignancies

• osteomyelitis

• some metal ions (zinc, silver)

• electronic implants

What are the uses for microcurrent?

• no muscle contraction

• analgesia

• fracture healing

• wound healing

• tendon and ligament healing

What is the waveform for non-invasive fractures?

wear on skin near fracture sit, biphasic AC or pulsed DC

What is the waveform for invasive fractures?

implanted devices after spinal fusion surgery, DC

What is the use of biofeedback?

• the use of instrumentation to bring specific events to conscious awareness

• utilized to receive info related to motor performance, kinesthetic performance, or physiologic response

• allows pts to make small changes in performance and provides immediate, real-time feedback

Describe biofeedback uses for muscle relaxation.

• start with electrodes closer together and a low sensitivity

• progress to higher sensitivity with electrodes further apart

• may also use imagery or other relaxation techniques

Describe biofeedback uses for muscle re-education.

• start with electrodes farther apart and high sensitivity

• progress to a lower sensitivity with electrodes closer

• also progress to functional movements with muscle contraction

• may use facilitation techniques (tapping, vibration)

What are therapeutic effects of biofeedback?

• decreased accessory muscle use

• decreased muscle spasm

• decreased pain

• improved muscle strength / recruitment

• muscle relaxation

• neuromuscular control

What are indications for biofeedback?

• bowel / bladder incontinence

• hemiplegia

• impaired motor control

• muscle spasm

• muscle weakness

• pain

• SCI

What are contraindications for biofeedback?

• dermatological condition (eczema, psoriasis)

• allergy to electrodes

• pts who cannot understand the instructions

• pts with pacemakers

• not over the eyes or other sensitive tissues