4) Electric, Mechanical, and Light Therapy Flashcards
_____ can produce specific physiological events and target specific tissues
- Type of current
- Current’s parameters (intensity, phase duration, and pulse frequency)
- Electrode size and arrangement
Electrical stimulation has little, if any, direct effect on
- Cellular level inflammation response
Direct current
- Uninterrupted, one-directional flow of electrons
Continuous current flow on only one side of the baseline as the electrons travel from (direct current)
- Cathode (negative pole) to the anode (positive pole)
Example of direct current used therapeutically
- Iontophoresis
Alternating current [AC]
- Cyclically changes from positive to negative
Pulsed current
- Flow of electrons are interrupted by discrete periods of noncurrent flow
Excitable tissues
- Nerves, muscle fibers, and cell membranes
- Influenced directly by the electrical current
Electrical current prefers to follow
- The path of least resistance
- Those formed by muscle, nerves, effusion, and blood
Electrodes introduce the current to the body from the stimulator via
- The electrode leads, forming a closed circuit
As the size of the electrode increases
- Current density decreases
Electrodes are close together
- Current flows superficially, forming a relatively small number of parallel paths
Increasing the distance between electrodes
- Current can reach deeper into the tissues
Subsensory level
- Point at which the output intensity rises from zero to the point where the patient first receives a discrete electrical sensation
- This type of stimulation does not appear to cause therapeutic benefits
Sensory level
- Only depolarizes sensory nerves; this level is found by increasing the output to the point at which a slight muscle twitch is seen or felt, and then decreasing the output intensity by approximately 10%
Motor level
- An intensity that produces a visible muscle contraction without causing pain
Noxious level
- Current applied at an intensity that stimulates pain fibers
Muscle fiber level
- Stimulation is applied with a long phase duration and output intensity that directly causes muscle fibers to depolarize
Accommodation
- Nerve’s rate of depolarization decreases while the depolarization stimulus (an electrical current) remains unchanged
- Require increasingly intense stimulus throughout the treatment to reach the depolarization threshold
Habituation
- CNS process of filtering out a continuous, nonmeaningful stimulus
- Tolerance to the stimulus developed across multiple treatments
Neuromuscular re-education
- “Teaching” a muscle how to contract again
- Low-duty cycle = muscle relax and recover between contractions
- Pulse frequency must produce tetanic contraction (60 pps)
Neuromuscular re-education protocols should not be administered when
- Tendinous attachment is not secure
- Muscle cannot tolerate the tension
- Joint motion is contraindicated
When the goal is to increase the muscle’s strength
- Electrically induced muscle contractions can supplement but should not substitute for voluntary contractions
The functional load placed on the muscle must be equal to at least
- 30% to 60% of maximum voluntary isometric contraction [MVIC]
If the duty cycle is too high
- Premature fatigue can occur because of increased use of the phosphocreatine system
The process of increasing muscle strength, power, endurance, and proprioception is used
- To improve functional outcomes following surgery
The use of electrical stimulation to strengthen muscle prior to surgery results in
- Improved post-surgical recovery, especially in the quadriceps
Electrical stimulation simply masks the pain or encourages the body to release
- Pain-controlling endogenous opiates
_____ activate the gate mechanism of pain modulation
- High-pulse frequency, short-phase duration, sensory-level currents
High-pulse frequency (more than 80 pps) motor-level stimulation triggers the release of
- Enkephalins
Low-pulse frequency, moderate-pulse duration, high-intensity stimulation, and noxious-level stimulation also activate
- The spinal gait
- Additive effect of stimulating the release of the body’s natural opiates—β-endorphin
Muscle contractions are needed for electrical stimulation to increase
- Blood flow in muscle
- Electrically induced contractions increase local blood flow approximately the same amount as voluntary contractions
The increased blood flow may be caused by the release of
- Endothelial relaxing factors that cause vasodilation and the associated oxygen demand of muscle contractions
Sensory-level stimulation does not evoke changes in
- Muscle or skin blood flow
Low-intensity DC or high-voltage pulsed stimulation may reduce
- Time needed for superficial wound healing to 1.5 to 2.5 times faster
_____ is recommended for advanced wound care using electrical stimulation
- Specialized/advanced training
Sensory-level stimulation is theorized to
- Inhibit edema formation by preventing the fluids, plasma proteins, and other solids from escaping into surrounding tissues
If edema has already formed
- Motor-level stimulation assists the venous and lymphatic systems in returning the edema back to the torso, where it can be filtered and removed from the body
Muscular contractions encourage venous and lymphatic return by
- Squeezing the vessels, moving the fluids proximally
- “Milking” the fluids out of the area
Current must produce a tetanic contraction that forces the fluids proximally along the extremity and then is followed by
- A relaxation period (e.g., duty cycle)
- A 50% duty cycle is then used to obtain the desired off-and-on contractions
Bone growth generators
- Attempt to produce electromagnetic fields that mimic the normal electrical signals produced by bone or to activate the bone’s piezoelectric properties
- Encourages the deposition of calcium through increased osteoblastic activity
- Prescribed only in extraordinary circumstances such as certain nonunion fractures and require long-term treatments (6 months or more)
E-stim contraindications
- Exposed metal implants
- History of seizures
- Sensory or mental impairment
- Unstable fractures
E-stim precautions
- Menstruation
- Areas of nerve sensitivity
- Communication impairments
- Severe obesity
- Electronic monitoring equipment
_____ can reduce the effectiveness of electrical stimulation pain control techniques
- More than 200 mg of caffeine
Transcutaneous electrical nerve stimulation (TENS)
- Electrotherapeutic approach to pain control
- Alters the perception of pain through the use of a biphasic electrical current
Electrical stimulation may reduce pain through
- Activation of the gate control mechanism
- Centrally through the release of endogenous opiates
TENS is effective in management of
- Acute or chronic musculoskeletal pain
TENS and pain control
- Depolarizes sensory, motor, or nociceptive nerves
- Decreases the conductivity and transmission of noxious impulses from the small pain fibers to the CNS
- The longer the patient has been experiencing pain, the more treatments required
Conventional TENS treatment
- High-pulse frequency (60 to 100 pps), short-pulse duration, and sensory-level intensity
- Stimulates A-beta fibers to activate the pain-modulating gate at the spinal cord level
True noxious-level stimulation is not actually obtained because
- Limited phase duration found on TENS generators is too short to activate C fibers
During the early stages of rehabilitation, patients using TENS have demonstrated the ability to
- Reduce the need for pain medication and a more rapid return to active exercise relative to patients not using TENS
Neuromuscular electrical stimulation (NMES)
- Muscle re-education, reduction of spasticity, delaying atrophy, and muscle strengthening
Generators for NMES use a wide range of waveforms, but the majority of the units currently on the market use
- Biphasic wave, but alternating currents (see “Russian stimulation”) penetrate deeper into the muscle
Iontophoresis
- The introduction of ionized medications into subcutaneous tissues using a low-voltage direct current
Medication types most commonly used for iontophoresis
- Anesthetics
- Analgesics
- Anti-inflammatory agents
Iontophoresis has been shown to deliver medication to depths of
- 6 to 20 mm below the skin
Anti-inflammatories used with iontophoresis
- Dexamathasone (-)
- Hydrocortisone (-)
- Salicylate (-)
Edema meds for iontophoresis
- Hyaluronidase (+)
- Salicylate (-)
- Mecholyl (+)
Meds for muscle spasm iontophoresis
- Calcium (+)
- Magnesium (+)
Analgesics for iontophoresis
- Lidocaine (+)
- Magnesium (+)
Scar tissue meds for iontophoresis
- Chlorine (-)
- Iodine (-)
- Salicylate (-)
Meds for open skin lesion iontophoresis
- Zinc (+)
Acetic acid iontophoresis
- Tx of insertional Achilles tendonitis
- Heterotrophic ossification
Iontophoresis medication dosage
- Measured in terms of milliamperes per minute (mA/min)
- Based on the relationship between the amperage of the current and the treatment duration
- Current amperage (mA) × Treatment duration (min) = mA × min
Most iontophoresors use a dose-oriented treatment protocol where
- User indicates the desired treatment dose
- Generator calculates the duration and intensity of the treatment
Biophysical effects of iontophoresis
- Depends on the medication used during the treatment
- Can penetrate 6 to 20 mm below the skin’s surface
When an anti-inflammatory or anesthetic mixture is used for iontophoresis, the onset of relief may take
- 24 to 48 hours
- Immediate relief is sometimes reported
Delivery electrode
- “Drug electrode”
- Serves as the active electrode
- Return electrode serves as the dispersive electrode
Intermittent compression units
- Assist in venous and lymphatic drainage
- Create a pressure gradient that forces fluid out of the extremity through the venous system
- Spreads solid matter proximally along lymphatic ducts
Types of intermittent compression units
- Filled with air (pneumatic compression)
- Chilled water (cryocompression)
- May inflate as a single unit or sequentially
The ON/OFF cycle of intermittent compression units
- Assists in milking or pumping edema out of the extremity
Intermittent compression contraindications
- Deep vein thrombosis
- Local superficial infection
- Congestive heart failure
- Acute pulmonary edema
- Displaced fractures
Continuous passive motion (CPM)
- Motorized devices that move one or more joints through a pre-set range of motion at a controlled speed
- Predominantly for knee
“Motion that is never lost need never be regained. It is the regaining of movement that is painful.”
- When the injured joint is kept in motion, the unwanted effects of immobilization on muscle, tendons, ligaments, articular and hyaline cartilage, blood supply, and nerve supply are reduced
As the cycle between flexion and extension is repeated, the change in pressure creates a pumping effect that circulates the synovial fluid; The circulating fluid may assist in the removal of
- Joint hemarthrosis
- Periarticular edema
- Blood from the tissues surrounding the joint
When given free rein to control the ROM, patients, using comfort as their guide, increase their ROM by
- 6 to 7 degrees per day
CPM is more effective in
- Increasing ROM caused by soft tissue restriction than static stretching
Total end range time
- Longer time spent at the terminal ROM increases ROM
CPM and edema reduction
- Not clearly understood
- Varies based on the body part and condition being treated
- Significant edema reduction after arthroplasty of the knee and ankle, after anterior cruciate ligament (ACL) surgery, for knee inflammatory conditions, and hand edema has been documented
CPM and _____ should assist in venous and lymphatic return by “milking” the muscle
- Elevation of the body part
CPM is not used as an acute pain control technique
- Reduction in edema or muscle spasm, as well as deterrence of functional shortening, would aid in limiting pain
- Movement of the joint activates afferent nerves located in the muscle, joint, and skin, and possibly provides pain control through the gate mechanism
CPM contraindications
- Unwanted joint motion and the associated stresses on bones and joint structures are the primary contraindications to CPM
- Unstable fractures
- Uncontrolled infection
- Spastic paralyses
CPM precautions
- History of deep vein thrombosis
- The type of CPM, arc of motion, and speed of motion should be adjusted based on the physician’s [your] recommendations for the pathology being treated
Therapeutic massage is an effective treatment for
- Promoting local and systemic relaxation or invigoration
- Increasing local blood flow
- Breaking down adhesions
- Encouraging venous and lymphatic return
Effleurage
- Stroking of the skin
- Deep = force fluids in direction of stroke
- Superficial = relaxation
- Fast = stimulates tissues and encourages blood flow
Petrissage
- Lifting and kneading
- Stretches muscle fiber and fascia from the skin and scar tissue
Friction massage
- Deep pressure
- Mobilization, tissue separation, breakup of scar tissue
Active assisted massage
- Combo of compression with broadening and muscle stripping
- Stretch and lengthen muscles to increase ROM
Neuromuscular massage
- Ischemic compression
- Decrease hypersensitivity and hypertonicity in taut muscle bands
Tapotement
- Tapping or pounding
- Promote relaxation
- Desensitization of skin’s nerve endings
Vibration
- Rapid shaking
- Increase blood flow
- Systemic invigoration of tissues
Friction massage (transverse friction)
- Circular or cross-fiber (transverse)
- Mobilizes muscle fibers separating adhesions in muscle, tendon fibers, or scar tissue that restrict motion and cause pain
- Used to facilitate local blood perfusion
Friction massage (transverse friction) is used in the treatment of
- Trigger points
- Tendinitis
- Postsurgical scars
- Other forms of joint adhesions
Transverse friction massage purpose
- Increase inflammatory response to stimulate healing
- Use strong pressure in perpendicular direction to fibers (7-10 minutes, every other day)
Myofascial release involves the combination of
- Traditional effleurage, pétrissage, and friction massage strokes with simultaneous stretching of the muscles and fascia
- Goal: obtain relaxation of tense or adhered tissues and restore tissue mobility
Myofascial release invovles
- Pulling the tissues in opposite directions
- Stabilizing the proximal or superior position with one hand while applying a stretch with the opposite hand
- Using the patient’s body weight to stabilize the extremity while a longitudinal stress is applied
Creep
- Fascia will elongate when a slow, moderate-intensity force is applied to it
Graston technique
- Instrument-assisted soft tissue mobilization [IASTM]
- Used to break down scar tissue and fascial restrictions
- Instrument allow precise and consistent pressure application
- Specially designed lubricant to ensure glide over skin
Low-level laser therapy (LLLT)
L ight A mplification of S timulated E missions of R adiation
LASER consists of
- Highly organized light (photons) that elicit physiological events in the tissues
- Photons emitted during LLLT activate certain skin receptors that stimulate or inhibit physiological events; these effects are caused by activation of chromophores, parts of a molecule (generally melanin and hemoglobin) that absorb light having a specific color (wavelength)
The Food and Drug Administration (FDA) has approved LLLT for the treatment of
- Carpal tunnel syndrome
- Shoulder and neck pain
Laser energy can stimulate tissues at depths up to
- 2 cm below the surface of the skin
Current evidence suggests that the biophysical benefits are related to
- Photomechanical or photochemical, rather than photothermal effects
Direct effects of LASER
- Effects that occur from the absorption of photons
Indirect effects of LASER
- Effects produced by chemical events caused by the interaction of the photons emitted from the laser and the tissues
LLLT can produce
- Anti-inflammatory or proinflammatory responses that affect healing
Lasers are used to assist in the healing of
- Superficial wounds (skin ulcerations, surgical incisions, and burns)
- Absorption of photons causes increased ATP synthesis, speeds cell metabolism, encourages free radical release
- Aqlso increases collagen content and increases the tensile strength of wounds
Contraindications of LLLT
- Cancerous tumor or growth
- Directly over eyes
- Pregnancy
Kinesiotaping (KT)
- Noninvasive treatment to relive pain and musculoskeletal functions
- Improves blood and lymph circulation by removing tissue fluid and bleeding that are supposed to be attributed to pain and muscle and fascia function
Hypothesized that kinesiotaping works by
- Activating neurological and circulatory systems to help to relieve pain
- Prevent over-contraction
- Facilitate lymphatic drainage
- Improve joint position and kinesthetic awareness
Extracorporeal shock wave therapy (ESWT)
- Non-invasive modality involves high frequency pressure wave delivery to targeted tendon through the skin
- Promotes revascularization
- Stimulates nerve fibers to produce analgesia
- Induce tissue and bone healing and functional improvement
