Physical Agent Modalities (PAMs)

Week 7

AOTA Position on PAMs

OTPs may use PAMs in preparation for, or concurrently with, purposeful and occupation based activities or interventions that ultimately enhance engagement in occupation

Superficial Thermal Agents

Applied to skin; reaches only superficial tissues. hydrotherapy/whirlpool,
cryotherapy, Fluidotherapy , hot packs, paraffin, water, infrared, and other commercially available superficial heating and cooling technologies

Deep Thermal Agents

Include but are not limited to therapeutic ultrasound, phonophoresis, short-wave diathermy, and other commercially available technologies

Electrotherapeutic Agents

Use electricity and the electromagnetic spectrum to facilitate tissue healing,
improve muscle strength and endurance, decrease edema, modulate pain, decrease the inflammatory process, and modify the healing process

Mechanical Devices

Include but are not limited to vasopneumatic devices and continuous passive motion (CPM)

Cryotherapy

• Commonly used in the treatment of acute injuries or trauma for decreasing spasticity, spasms, or edema

• Results in a withdrawal of heat from the body, lowering the temperature of the tissue

• Superficial cold techniques exert their effect on the tissue to depths of 1 to 2 cm

• Cold is easily applied, decreases tissue temperature, decreases
  metabolic rate, and causes vasoconstriction that decreases blood flow

Cryotherapy Indications for Use

• Whole body cooling

• Presence of edema, post exercise edema and pain, arthritic exacerbation or flare up, acute bursitis/tendonitis, spasticity, and acute or chronic pain secondary to muscle spasm and post exercise to maintain soft tissue elongation

• PRICE = protection, rest, ice, compression, and elevation

Cryotherapy Precautions

• Improper application of cold can cause tissue damage due to vasoconstriction, ischemia, and thromboses

• Tissue damage can occur if tissue is cooled to 59 F

• Extended application can cause temporary or permanent nerve damage or terms in nerve conduction

• Patients with impaired sensations

Cryotherapy Contraindications

• Cold urticaria, cryoglobulinemia, and Raynaud’s disease

• Patients with hypertension, impaired sensation, compromised circulation, PVD, history of frostbite

• Any medical condition in which vasoconstriction will aggravate symptoms

• Open wounds or skin conditions ex. psoriasis

Therapeutic Heat

Application of superficial heat increases tissue temp. and is used to increase extensibility of collagen tissue, decrease muscle spasm, decrease
pain, increase metabolic rate, and provides subjective comfort

• To achieve a therapeutic biophysiological effect, tissue temperature must be elevated and sustained between 104 °F and 113 °F

Therapeutic Heat: Indications for Use

Increased tissue temperature stimulates vasodilation, increasing blood flow to the tissue along with histochemical components oxygen, and nutrition to the area of injury, which also facilitates healing.
• Pain relief is accomplished through neural transduction of the
heat
• When used with developmental and therapeutic stretching,
heat has been demonstrated to be effective for increasing range of motion

Therapeutic Heat: Precautions

• Older adults

• Individuals who are obese, frail

• Children

Monitor BP, respiration, skin color, sweating, or discomfort

Therapeutic Heat: Contraindications

Impaired sensation

Poor thermal regulation

Tumors/cancer

Acute inflammation

DVT

Pregnancy - full immersion

Primary repair of tendon or ligament

Therapeutic Heat: Whirlpool

• used to remove gross contaminants

• To remove toxic debris such as surface bacteria, improve circulation, to decrease wound pain

• To decrease suppuration (formation of pus), debride an area, decrease heat/fever (water temperature),

• Soak and soften dressings for removal, and to facilitate healing

• Can control temp of water and agitation of bubbles/water

• Water = buoyant, can perform graded mobilization and visually see the extremity

• Never exceed 110F

Therapeutic Heat: Fluidotherapy

Provides a variety of dosages of dry, stable heat using convection and a cellulose medium.
• Therapeutic goals include desensitization, reduction in pain, increased range of motion may be effective with complex regional pain
syndrome.
• Fluidotherapy combines physiological effects of heat and tactile stimulation and can be used for desensitization

Hot Packs

Form of moist heat that uses conduction and are more efficient at warming body

Used for superficial heating and home use

Increases circulation, increase metabolism, decrease pain, muscle spasm, and joint or soft tissue stiffness

Contrast Baths

• Involves the repetitive application of cold and then heat in an alternating pattern. Frequently used though research is minimal and support is primarily anecdotal

• Theoretically, contrast baths decrease edema, increase blood flow, and decrease pain and joint stiffness through the alternating pumping mechanisms of vasoconstriction and vasodilation of
  blood vessel

• Cold 50-59F and heat 100F to 104F

• 10 mins warm 1 min cold, 4:1 ratio additional 2x

Paraffin Bath

• Moderate to vigorous to localized areas of small joints

• 118F-135F

• Primarily used to decrease stiffness and increase ROM, while decreasing pain

• Check temp of paraffin, skin integrity, and sensation

• Immerse area in bath, make sure to NOT touch sides or bath

• After immersion immediately remove 2-3 seconds and repeat for 10 mins

• Plastic bag, towel, placed on area to retain heat and is worn for 20 mins

Therapeutic Ultrasound

Acoustic energy that is inaudible that creates pressure waves transmitted into underlying tissue

Heat deeper tissues and heal tissue

Thermal

Nonthermal - promote tissue healing

Electrotherapy

• Use electricity and electromagnetic spectrum to facilitate tissue healing, improve muscle strength and endurance, facilitate or stabilize movement, decrease edema, pain, and decrease healing process

• Strengthens and reinforces patterns of movement and function

• Prevents disuse atrophy

• 
  

Electrotherapy: Contraindication

• Over thoracic region

• Pacemakers, defibrillator, deep brain stimulator, implanted electrical device

• Phrenic nerve or bladder

• Anterior neck, carotid sinus, transcerebral or individuals with epilespy

• PVD, VT, thrombophlebitis

• Over eyes or reproductive organs

• Active cancer, infection, active hemorrhage

• Pregnant people

• Near diathermy devices

Electrotherapy Precautions

• Patients with hypertension or hypotension

• Patients with obesity may require higher levels

• Patients unable to provide clear feedback

• Over areas with pathology of myelin sheath

• Over areas with pathology of the synapse points

• Patients with skin condition

• Patients with autonomic dysreflexia

• Over areas with pathology of cell body (polio)

Transcutaneous electrical nerve stimulation (TENS)

Alternating current (AC) for pain control

NMES

Neuromuscular electrical stimulation

Ac for strengthening, neuromuscular reeducation, preventing disuse atrophy, muscle spasm or edema

High voltage Pulsed current (HVPC)

Wound healing and edema control

Electrical Muscle Stimulation (EMS)

Direct current (DC) for denervated muscle stimulation

Functional Electrical Stimulation (FES)

AC as an orthotic substitute or functional activity such as feeding

Iontonphoresis

DC for transcutaneous drug delivery

Transcutaneous Electrical Nerve Stimulation (TENS)

• Pain control

• Low voltage electrical pulses to the nervous system using surface electrodes

• Nonpharmacological intervention that activates endogenous opioid system in peripheral and central nervous system to modulate pain

TENS Treatment Parameters

• Pulsed or alternating currents with variety of combo of stimulation patterns

• Characterized by pulse amplitude, duration or width, and frequency

• Subsensory level, sensory level, motor level, and noxious level

NMES Clinical Reasoning

• Select the muscle or muscle group to stimulated

• Frequencies (pps) should be chosen that achieve the desired outcome, yet are comfortable for pt.

• 25-35 pps for weakness and 35-50 pps for health muscles

• Frequence should produce visible muscle contraction

NMES Monopolar Stimulation

• Uses a small active electrode over motor point of muscle

• Dispersive pad is used on same side of body

NMES Bipolar Stimulation

Uses two electrodes placed over a single muscle group or group of muscles at each end of muscle belly.

Current is passed through the muscle belly and results in contraction

NMES Electrode Placement

Skin should be cleaned and dried prior to electrode application

Skin check before and after

Placement varies depending on what muscle group is goal

Clinicians should meet all state or institutional regulatory or licensure guidelines

Transcutaneous Electrical Nerve Stimulation (TENS)

• Pain control

• Low voltage electrical pulses to NS using surface electrodes

• Provides analgesic effect that facilitates occupational performance

• Nonpharm. intervention that activates endogenous opioid system in peripheral and CNS to modulate pain

• Afferent fibers activates descending inhibitory systems decreasing pain

TENS Sensory Level Stimulation

Tingling sensation

Sensory TENs is delivered at pulsed, higher frequencing with short pulse duration

50 to 200 pps with pulse width of 20-100 microseconds

Pain relief = short, little over an hour

Electrodes should be placed over motor points that correlate with location of pain or on segmental nerve roots