Use of Physical Agents in Therapy

These flashcards highlight key concepts regarding physical agents and their application in therapy, offered in various formats to aid in exam preparation.

What are physical agents?

Therapeutic modalities (such as thermal, mechanical, or electrical agents) used in physical therapy to enhance recovery from injury or illness, manage pain, reduce inflammation, and improve overall function and mobility.

Modalities

Specific therapeutic tools or methods applied in physical therapy, including categories like thermal (e.g., hot packs, ice), mechanical (e.g., traction, compression), and electromagnetic (e.g., electrical stimulation, ultrasound) agents.

Pathology

A physical condition, disease, or injury that directly results in an impairment or dysfunction within a body system or structure, often requiring medical or rehabilitative intervention.

Impairment

A loss or abnormality of normal function in an anatomical structure or physiological system, such as reduced range of motion, decreased strength, or sensory deficits, often resulting from a pathology.

Functional Limitation

A restriction in an individual's ability to perform routine tasks or activities required for daily living, work, or recreation, often due to an underlying impairment (e.g., difficulty walking, lifting, or dressing).

Disability

A condition that substantially limits an individual's ability to engage in normal activities of daily living (ADLs) or participate fully in society, often stemming from functional limitations and environmental barriers.

Stages of Healing

The predictable biological phases of tissue repair and recovery after an injury, which include the initial Inflammation, followed by Proliferation (tissue rebuilding), and concluding with Maturation (tissue remodeling and strengthening).

Inflammatory Stage

The first stage of healing, typically lasting 3-7 days, characterized by a vascular and cellular response to injury, including vasoconstriction, vasodilation, clot formation, and migration of phagocytes to clean the injured area and protect it from further damage.

RICE

An acronym for Rest, Ice, Compression, and Elevation; a standard first-aid therapy primarily used in the acute inflammatory stage of injury to control swelling, reduce pain, and prevent further tissue damage.

Proliferative Stage

The second stage of healing, generally lasting from a few days up to 20 days, during which new capillaries and granulation tissue form, fibroblasts synthesize collagen, and the wound begins to close, effectively rebuilding damaged tissues.

Maturation Stage

The final healing phase, beginning around 21 days post-injury and potentially lasting months to a year or more, where collagen fibers remodel and align according to mechanical stresses, increasing tissue strength, elasticity, and functionality.

Thermotherapy

The therapeutic application of heat, typically through modalities like hot packs or paraffin wax, to increase blood flow (vasodilation), reduce muscle spasm and stiffness, decrease pain, improve tissue extensibility, and promote relaxation to expedite healing.

Cryotherapy

The therapeutic application of cold, often via ice packs or cold immersion, to cause vasoconstriction, decrease metabolic rate, reduce nerve conduction velocity, thereby effectively minimizing swelling, inflammation, muscle spasm, and acute pain.

Ultrasound

A modality that uses high-frequency sound waves to penetrate tissues, producing both thermal effects (deep tissue heating to increase circulation and tissue extensibility) and non-thermal effects (cavitation and acoustic streaming to promote cellular activity and healing), for pain relief and tissue repair.

Electrical Stimulation (E-stim)

A modality that uses controlled electrical currents passed through electrodes on the skin to elicit physiological responses, such as sensory nerve depolarization for pain gate theory (e.g., TENS), motor nerve depolarization for muscle contraction and strengthening (e.g., NMES), or ion movement for tissue healing.

Contraindications

Specific circumstances, conditions, or patient characteristics (e.g., implanted devices, certain medical diagnoses, acute injuries) under which a particular therapeutic modality should absolutely not be used, as it could potentially cause harm or exacerbate a pre-existing condition, thereby ensuring patient safety.

Hot Packs

A superficial thermal modality consisting of silica gel packs heated in a hydrocollator (typically to 158°-167°F or 70°-75°C) and wrapped in multiple layers of toweling, applied to the skin for 15-20 minutes to provide moist heat therapy, increasing local circulation and muscle relaxation.

Paraffin Wax

A superficial thermal modality involving dipping body parts (most commonly hands or feet) into warmed paraffin wax (typically 113°-122°F or 45°-50°C) multiple times to create a layered glove, which then slowly transfers heat to the tissues to increase circulation, reduce stiffness, and improve range of motion, particularly in small, irregular joints.

TENS

Stands for Transcutaneous Electrical Nerve Stimulation; a common type of E-stim that delivers low-voltage electrical current through electrodes placed on the skin, primarily used for symptomatic pain relief by stimulating sensory nerves to activate the pain gate mechanism or release endorphins.

NMES

Stands for Neuromuscular Electrical Stimulation; a type of E-stim specifically designed to stimulate motor nerves, causing muscle contractions to enhance muscle strength, re-educate muscles, improve range of motion, reduce atrophy, or manage muscle spasms.

IFC

Stands for Interferential Current; an E-stim modality that uses two alternating medium-frequency electrical currents from different channels that 'interfere' with each other within the body's tissues. This creates a beat frequency aimed at providing deeper penetration and broader coverage for pain relief or muscle stimulation in larger areas.

HVPC

Stands for High-Voltage Pulsed Current; a monophasic E-stim waveform characterized by short-duration, high-peak intensity pulses, primarily used for accelerating wound healing (by promoting cellular migration and antibacterial effects), reducing acute edema (through ionic repulsion), and managing pain.

Russian Stimulation

A specific type of NMES characterized by delivering medium-frequency (typically 2500 Hz) alternating current in bursts of 50 bursts per second, causing strong, smooth muscle contractions primarily used for strengthening muscles, reducing muscle atrophy, and facilitating neuromuscular re-education, especially in post-surgical or weakened muscles.

Duty Cycle in Ultrasound

In ultrasound therapy, the Duty Cycle represents the percentage of time the ultrasound energy is being delivered during a treatment session. A 100\% duty cycle means continuous delivery (primarily thermal effects), while a lower duty cycle (e.g., 20\% or 50\%) means pulsed delivery (favoring non-thermal, mechanical effects for tissue healing with less heat).

Frequency in Ultrasound

In ultrasound therapy, the Frequency refers to the number of sound wave cycles per second, measured in Megahertz (MHz). A 1 MHz frequency targets deeper tissues (up to 5 cm), while a 3 MHz frequency targets more superficial tissues (up to 2.5 cm), making it a key parameter for depth of penetration.

Intensity in Ultrasound

In ultrasound therapy, the Intensity refers to the power of the sound wave per unit area, measured in Watts per square centimeter (W/cm^2). It is adjusted to achieve desired therapeutic effects; higher intensities (0.8-2.0 W/cm^2 in continuous mode) are used for thermal effects, while lower intensities (0.1-0.5 W/cm^2 in pulsed mode) are used for non-thermal, healing effects.

Traction

A mechanical modality, applied either manually or with specialized equipment, that involves applying a pulling force to a body segment, most commonly the spine (cervical or lumbar). Its purpose is to stretch soft tissues, separate joint surfaces, decompress nerve roots, and alleviate pressure on spinal discs and joints, thereby reducing pain and promoting relaxation.

Compression Therapy

The therapeutic application of external pressure to a body part, using bandages, garments, or pneumatic devices, primarily to improve venous and lymphatic return, reduce edema and swelling, prevent deep vein thrombosis (DVT), and provide support for weakened tissues or joints.

E-stim Parameters

Adjustable settings that determine the characteristics and therapeutic effects of electrical stimulation, including waveform, pulse rate/frequency (Hz), pulse duration/width (\mu s), amplitude/intensity (mA), on/off time (duty cycle), and ramp time.

Common Contraindications of Thermotherapy

Key conditions where thermotherapy should not be used include: acute injuries or inflammation (can exacerbate swelling), impaired sensation (risk of burns), malignancies (may increase tumor growth or metastasis), areas of acute bleeding/hemorrhage (can increase blood flow and bleeding), cardiac insufficiency, and peripheral vascular disease (due to inability to dissipate heat effectively).

Cryotherapy Precautions

Important considerations and conditions requiring caution with cryotherapy include: cold intolerance (unusual pain/numbness), open wounds (can delay healing), and peripheral vascular disease or Raynaud's phenomenon (impaired circulation could worsen tissue damage), hypertension (can cause transient increase in blood pressure) and superficial nerves.

Ultrasound Contraindications

Critical conditions where ultrasound should not be used include: malignancies or areas of suspected tumor growth (can promote metastasis), pregnancy (over abdomen or pelvis), implanted pacemakers or other electronic devices (may interfere with function), areas of infection (can spread infection), over active epiphyseal plates in children, and thrombophlebitis.

E-stim Contraindications

Key conditions where E-stim should not be used include: presence of implanted cardiac pacemakers, defibrillators, or other electronic devices (risk of interference), pregnancy (over abdomen/pelvis/lower back), active skin irritation or open wounds under electrodes (risk of increased irritation/infection), over carotid sinus, areas of thrombosis, and known seizure disorders.

Traction Contraindications

Critical conditions where traction should not be used include: spinal instability or recent spinal surgery (risk of further injury), acute fractures or dislocations (risk of displacement), significant osteoporosis or bone tumors (risk of fractures), acute inflammatory conditions or infections affecting the spine, and uncontrolled hypertension or vascular compromise in cervical traction.

Compression Contraindications

Crucial conditions where compression therapy should not be used include: diagnosed Deep Vein Thrombosis (DVT) or suspected DVT (risk of embolus), severe arterial insufficiency (could further compromise circulation), acute local skin infection or cellulitis (can spread infection), uncontrolled congestive heart failure, and pulmonary edema.

General Considerations for Modality Use

Before applying any modality, always assess patient's circulation and sensation, thoroughly inspect skin integrity in the treatment area, monitor patient comfort and response throughout the treatment, and consult with the supervising physical therapist for any complex cases, unusual patient responses, or if unsure about a contraindication.

Standard Therapy Focus - Inflammatory Stage

During the Inflammatory Stage (3-7 days post-injury), standard therapy focuses on minimizing swelling and pain, protecting the injured area, and preventing further damage, primarily through RICE (Rest, Ice, Compression, Elevation) and possibly gentle, pain-free passive range of motion to maintain joint mobility without stressing healing tissues.

Standard Therapy Focus - Proliferative Stage

In the Proliferative Stage (from week 1 to week 3 post-injury), therapy shifts to promoting optimal tissue healing, introducing gentle, controlled active and passive range of motion (ROM) exercises, light strengthening activities, and early scar tissue management to improve flexibility and tissue organization without disrupting new collagen formation.

Standard Therapy Focus - Maturation Stage

During the Maturation Stage (from week 3 to 1+ year post-injury), therapy emphasizes restoring full function and preventing re-injury. This involves progressive strengthening exercises with increasing loads, advanced proprioceptive and balance training, functional activity simulation, and sport-specific or occupation-specific training to prepare for a safe return to desired activities.

Example of Pathology

After a skiing accident, Linda suffered a rotator cuff tear, which is the specific pathology (injury/disease) causing her shoulder pain and inability to lift her arm.

What is a functional limitation?

A functional limitation is a restriction in an individual's ability to perform specific actions or daily tasks, such as difficulty lifting objects, putting on a shirt, walking stairs, or reaching overhead, often as a direct result of an underlying impairment.

What is disability?

A disability is a condition that significantly impacts an individual's ability to engage in activities of daily living (ADLs), roles, or participation in society, stemming from the interaction between health conditions, impairments, functional limitations, and environmental/personal factors.

What is cryotherapy used for?

Cryotherapy is primarily used in acute injuries and inflammatory conditions to reduce swelling (edema) and inflammation, alleviate acute pain, decrease muscle spasms, and limit secondary tissue damage by causing vasoconstriction and slowing metabolic activity.

What does the E-stim modality do?

The Electrical Stimulation (E-stim) modality uses controlled electrical currents to serve various therapeutic purposes, including alleviating pain (e.g., TENS), strengthening weakened muscles (e.g., NMES, Russian stim), reducing muscle spasms, improving circulation, and promoting wound healing (e.g., HVPC).

What is the purpose of ultrasound therapy?

The purpose of ultrasound therapy is to utilize high-frequency sound waves to promote tissue healing (through non-thermal effects like cellular activity and collagen synthesis), reduce pain, decrease muscle spasms, and increase tissue extensibility (through thermal effects, particularly useful for collagen-rich tissues like tendons and ligaments).

What is the purpose of traction in therapy?

The purpose of traction in therapy is to apply a pulling force to the spine or other body parts to stretch soft tissues (muscles and ligaments), decompress nerve roots (e.g., in radiculopathy), reduce disc protrusion, separate joint surfaces, and thereby alleviate pressure on spinal discs and facet joints, often providing significant pain relief.

Purpose of compression therapy?

The primary purpose of compression therapy is to enhance venous and lymphatic return by applying external pressure, which effectively decreases swelling (edema), helps prevent deep vein thrombosis (DVT), reduces scar tissue formation, and provides support for lax or unstable joints and soft tissues.

Purpose of thermotherapy?

The purpose of thermotherapy is to apply heat to increase local blood flow (vasodilation), thereby improving nutrient delivery and waste removal, to reduce muscle stiffness and spasm, alleviate chronic pain, increase soft tissue extensibility (making stretching more effective), and promote general relaxation.