2022 Superficial Thermal Lecture

Superficial Thermal
Modalities

Therapeutic heat agents refer to any modality that will increase the
temperature of the skin and superficial subcutaneous tissue

1

Learning Objectives

After completing this lesson, you should be able to:
▪ Define the term “superficial thermal agent.”
▪ Differentiate between the two commonly used methods of heat
transfer: conduction & convection.
▪ Discuss the four biophysical effects of heat.
▪ Describe the physiologic response to tissue secondary to
temperature elevation.
▪ Differentiate between mild, moderate and vigorous dosages of
heat.
▪ List the indications, precautions, and contraindications that should
be considered when using superficial thermal agents.
▪ And describe the proper clinical applications for hot packs,
paraffin baths, fluidotherapy, whirlpool baths, and contrast baths.

Welcome to the presentation on superficial thermal modalities. The use of
therapeutic heat generally refers to any modality that can be applied to the
body which will increase the temperature of the skin and the superficial
subcutaneous tissue.
This lesson will specifically focus on the utilization of hot packs, paraffin
baths, fluidotherapy, whirlpool baths, and contrast baths, and address how
these thermal modalities can benefit patients.

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Background

• Ancient Greeks believed the sun’s radiation had natural
therapeutic qualities that could treat illnesses

• Greek word for “sun” is “helio” and is used to form
compound words such as “heliotherapy”

• In the 20th century, thermotherapy was used to categorize
the means of applying heat superficially to cause a
physiological response

• Today, thermal agents are used to achieve an increase in
cell metabolism, blood flow, and soft tissue elasticity by
elevating and sustaining tissue temperatures between
104oF – 113oF

The use of heat as a means to achieve a relaxing, soothing response has
been acknowledged for centuries.
The ancient Greeks believed the sun’s radiation had natural therapeutic
qualities that could treat illnesses. The Greek word for “sun” is “helio”
and is used to form compound words such as “heliotherapy,” which is
defined as “using the sunlight for the treatment of diseases.”
During the 20th century, thermotherapy was a general term used to
categorize the means of applying heat superficially that would cause a
physiological response when treating certain pathologic conditions.
Today, thermal agents are used to achieve an increase in cell metabolism,
blood flow, and soft tissue elasticity by elevating and sustaining tissue
temperatures between 104o – 113oF.

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Thermal Heat Transfer

Conduction

• Exchange of energy between two materials that have
two different temperatures

• Area with higher temperature will result in transfer
of energy to area with lower temperature until both
areas are equally heated

• For example, if a thermal physical agent is applied to
a patient’s skin, the heat will transfer from the agent
to the person’s extremity and increase the skin
temperature

There are two general methods of thermal heat transfer.
The first is through conduction, which involves an exchange of energy
between two materials that have two different temperatures.

• When an area with higher temperature comes into contact with an
area with lower temperature, it will result in the transfer of energy
to the area with the lower temperature and raise its temperature until
both areas are equally heated.

• For example, if a
thermal physical agent
is applied to the skin to
achieve a specific
physiologic response,
the heat will transfer
from the agent to the
patient’s extremity, and
thereby, increase the
skin temperature.

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Thermal Heat Transfer

Conduction

• Therapist must consider rate of temperature variance
during heat transfer:

– if transfer is too slow, desired therapeutic effect may not be
achieved

– if transfer is too rapid, it could burn the patient

• Understanding the balance between physiological condition
of patient’s tissue and rate of temperature increase is
critical for safe application of any thermal agent

• Modalities that involve conduction include hot packs,
paraffin baths, and contrast baths

A therapist must take into consideration the extent of temperature variance
when the heat is being transferred.

• If the transfer is too slow, the desired therapeutic effect may not
being achieved.

• Conversely, if the heat is transferred too rapidly, it could burn the
patient.

Understanding the balance between the physiological condition of the
patient’s tissue and the temperature variance is critical for the safe
application of any thermal agent.
Physical agent modalities utilized to transfer heat through conduction
include hot packs, paraffin baths, and contrast baths.

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Thermal Heat Transfer

Convection

• Transfer of heat through the movement of heated particles
• For example, when air or water molecules move across a

body part, the higher temperature of the medium will
transfer to the lower temperature of the patient
• Transfer of heat by convection is more efficient than
conduction because the medium is constantly moving, and
warmer thermal elements constantly come into contact
with area being treated
• Modalities that involve convection include fluidotherapy
and whirlpool baths

The second method of heat transfer is through convection and involves the
transfer of heat through the movement of heated particles.

• For example, when air or water molecules move across a body part,
a temperature variance will result because the higher temperature
created by the air or water will transfer to the lower temperature of
the patient.

However, this is in contrast to conduction since the physical agent is not in
continuous contact with the patient.

The transfer of heat by convection is more efficient than conduction
because the medium is continuously moving and its warm thermal
elements are constantly coming into contact with the area of the extremity
being treated.

With conduction, though, the same material remains in contact with the
patient. Thus, as the material begins to cool, its efficiency will decrease.

Physical agent modalities utilized to transfer heat through convection
include fluidotherapy and whirlpool baths.

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Biophysiological Response
of Heat

Purpose of applying a thermal agent is to increase
temperature of soft tissue to therapeutic range so a
certain physiological response will be achieved:

– increasing temperature of soft tissue between a range of
104o – 113oF can have therapeutic affect
o below 104oF, cell metabolism will not be
stimulated enough to achieve therapeutic
response
o above 113oF, catabolism and cell death will
usually occur

The purpose of applying a thermal agent is to increase the temperature of
the soft tissues to a specific therapeutic range so that a certain
physiological response will be achieved.
When the temperature of soft tissue is increased between the ranges of
104o – 113oF, it can have a positive therapeutic effect on the patient.
However, if the soft tissue is heated to a level less than 104oF, then the
cell metabolism will not be stimulated adequately enough to achieve a
therapeutic response.
However, if the same tissue is heated to a temperature level greater than
113oF, then catabolism and cell death will usually occur.

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Biophysiological Response
of Heat

• Depends on:

– intensity of heat
– modality used
– length of exposure
– surface area involved

To determine the extent of achieving a specific biophysiologic response
with a superficial heating agent, the therapist should consider

• the intensity of the heat,
• the modality that is used,
• the length of exposure time, and
• the surface area that is involved.

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Biophysiological Response
of Heat

• Superficial heating agents will penetrate
skin between 1 – 2 centimeters:

– one centimeter depth will elevate soft tissue
temperature 6 degrees

– two centimeters depth will elevate soft tissue
temperature 2 degrees

Superficial heating agents usually will penetrate the skin between 1-2
centimeters.
At a depth of one centimeter, the soft tissue temperature will elevate by 6
degrees, whereas at a depth of two centimeters, the temperature will only
elevate by 2 degrees.

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Biophysiological Response
of Heat

The application of thermal agents will cause biophysiological responses
such as the increase of blood flow, rate of cell metabolism, oxygen
consumption, capillary permeability, inflammation, and muscle
contraction velocity.
Conversely, they will decrease the fluid viscosity, pain, and muscle
spasm (by decreasing the pain and ischemia).

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Biophysiological Response
of Heat

• Immediate response will be an increase of blood
flow to the treated area
• As body temperature rises, blood vessels dilate
• Blood vessels that are more superficial dilate

greater than deeper blood vessels
• Additional flow of blood brings extra oxygen,

nutrients, and antibodies to the affected area

When a thermal agent is applied to an area of the body, the immediate
response will be an increase of blood flow to the area being treated.
As the body temperature rises, the blood vessels will dilate; the blood
vessels that are more superficial will dilate greater than the deeper blood
vessels.
Although the blood will act as a mechanism to counteract the increased
temperature, the additional flow will also bring an extra supply of
oxygen, nutrients, and antibodies to the affected area.

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Biophysiological Response
of Heat

• Increased body temperature will cause
metabolism to increase because of cellular
response:

– increase of 10oF causes cells’ metabolic rate to
increase twofold

– increase of blood flow provides additional
oxygen and means to remove cell by-products
through venous return

When there is an increase of the body temperature, the metabolism will
increase because of the cellular response.

• For example, if the temperature increases 10oF, the cells’
metabolic rate will increase twofold.

Associated with the metabolic increase is a demand for additional oxygen
as well as the creation of metabolites (as a by product of cell metabolism).
The increase in blood flow will also provide additional oxygen and cause
the removal of the cells’ by- products through venous return.

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Biophysiological Response
of Heat

• Application of heat to an extremity can aid
in pain relief and decrease muscle spasms:

– removal of local muscle metabolites
– reduction of muscle spindle’s sensitivity that

tend to stretch and cause pain

• Most muscle tissue will not be directly
affected by superficial heating modalities
since they lie too deeply

The application of heat to an extremity can aid in pain relief and decrease
the muscle spasms that a patient may be experiencing.

Since the blood flow will increase as
a result of the heat, the outcome will
be the removal of the local muscle
metabolites and the reduction of the
muscle spindle’s sensitivity that tend
to stretch and cause pain.

It also should be noted that most
muscle tissue will not be directly
affected by superficial heating
modalities since they lie too deeply.

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Biophysiological Response
of Heat

• Heat application can increase collagen
extensibility and lengthen soft tissue by
raising tissue temperature between 104o –
113oF for approximately 10 minutes

• Superficial treatment is useful for stretching
cutaneous scar tissue and superficial joint
capsules and tendons

Heat applications that are placed on soft tissue can assist in increasing the
collagen extensibility.
Research has substantiated that the way to increase the length of soft tissue
is to raise the tissue temperature between 104o – 113oF and then maintain it
at that range for approximately 10 minutes.
This superficial treatment is useful for stretching cutaneous scar tissue and
superficial joint capsules and tendons.

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Therapeutic Effects of
Superficial Heat Agents

• The two most commonly used superficial heating
agents are hot packs and paraffin wax applications

• Principal therapeutic goal associated with either
application is the reduction or modulation of pain

• Both agents can be effectively used as adjunct for
therapeutic occupation, functional activity, or an
associated movement that will enable purposeful
activity

The two most commonly used superficial heating agents are hot packs and
paraffin wax applications.
A principal therapeutic goal associated with either application is the
reduction or modulation of pain.
Hot packs and paraffin baths can both be used effectively as an adjunct for
a therapeutic occupation, functional activity, or an associated movement
that will enable involvement in a purposeful activity.

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Therapeutic Effects of
Superficial Heat Agents

• Understanding the physiological response of
temperature variation is necessary before selecting
the appropriate superficial thermal agent

• Elevating tissue temperature within a therapeutic
range is dependent on:

– rate the temperature is applied to the tissue
– duration of the application
– volume of the tissue

Understanding the physiological response of temperature variation is
necessary before selecting the appropriate superficial thermal agent.
When elevating tissue temperature within a therapeutic range, it will be
dependent on

• the rate the temperature is applied to the tissue,
• the duration of the application, and
• the volume of the tissue.

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Therapeutic Effects of
Superficial Heat Agents

• Important factor that influences physiologic
response of a superficial thermal agent is its
conductive nature

• Therapist can regulate amount conductive transfer
of energy by using different application
procedures

• Increasing or decreasing coupling media can
ensure there will be snug fit of area being treated

An important factor that influences the physiologic response of a
superficial thermal agent is its conductive nature.
However, the therapist can regulate the amount of conductive transfer of
energy by using different application procedures.

• For example, by increasing or decreasing the coupling media such
as using layered towels with hot packs or draping the hot packs
and securing them with Velcro ties can ensure there will be a
snug fit of the area being heated.

•

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Thermal Dosages

• Three levels of heat delivery to elevate tissue
temperature consist of mild, moderate, or vigorous
thermal doses

• Mild dosage level involves slight change in tissue
temperature < 104oF

• Dry heating pad or applying warm water soaks can
provide sense of relaxation:

– rate of temperature will increase slowly
– duration will be short
– temperature elevation will be low

The three levels of heat delivery to elevate tissue temperature consist of
mild, moderate, or vigorous thermal doses.

• A mild dosage level will involve only a slight change in tissue
temperature that does not exceed 104oF.

• A dry heating pad or applying warm water soaks are examples
of delivering mild doses that can provide a sense of relaxation.

The rate of temperature will increase slowly, the duration will be short,
and the temperature elevation at the site of the pathology will be low.

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Thermal Dosages

• Moderate dosage level:

– elevates tissue temperature between 102o –
106oF

– results in slight increase of blood flow
– effective when heat is indicated, but edema may

occur

A moderate dosage level will involve elevating the tissue temperature to a
point where it will be between 102o and 106oF, and will result in only a
slight increase of blood flow.
This dosage level is very effective when heat is indicated, but edema may
occur.

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Thermal Dosages

• Vigorous dosage level will result in marked
increase of blood flow in which tissue temperature
will rise between 107o – 113oF

• Beneficial for ischemic conditions and when heat
is indicated, and edema is not a concern:

– rate of temperature will increase rapidly
– duration will be relatively long
– temperature elevation will be high

A vigorous dosage level will result in a marked increase of blood flow in
which the tissue temperature will rise between 107o – 113oF.
This dosage level is beneficial for ischemic conditions and when heat is
indicated, and edema is not a concern.
The rate of temperature will increase rapidly, the duration will be
relatively long, and the temperature elevation at the site the pathology will
be high.

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Thermal Dosages

• Superficial heating agents used in OT clinics are
typically capable of providing moderate and
vigorous thermal dosages

• Application of superficial thermal agents can
rapidly increase subcutaneous tissue temperature
and patient’s body may not be capable of eliciting
an adequate vasodilation response to counteract
the temperature increase

• Sustained subcutaneous tissue temperature of
113oF or higher will cause tissue burns

The superficial heating agents that are used in most occupational therapy
clinics are typically capable of providing moderate and vigorous thermal
dosages.
Because the application of superficial thermal agents can rapidly increase
the subcutaneous tissue temperature, the patient’s body may not be
capable of eliciting an adequate vasodilation response to counteract the
temperature increase.
Consequently, when the subcutaneous tissue temperature is elevated to
113oF or higher, it will be unsafe and cause tissue burns.

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Hot Packs

• Provide moderate and vigorous doses of moist heat
• Range between 158o and 168oF
• Coupling media should be used to avoid burns and

may consist of:

– layers of dry Turkish towels placed between hot pack
and skin, or

– combination of commercial hot pack covers and Turkish
towels

– rule of thumb is there should be 6 layers of towels
between hot pack and skin

• Most effective when applied on flat body surfaces
or over large skin areas for 20 minutes

Hot packs are typically used to provide moderate and vigorous doses of
moist heat.
Since hot packs can range between 158o and 168oF, their usage will
necessitate the utilization of a coupling media to avoid burning the skin.

The coupling media may consist of layers of dry Turkish towels that are
placed between the hot pack and skin, or may consist of a combination of
commercial hot pack covers and Turkish towels.

• The rule of thumb is there should be 6 layers of towels between
the hot pack and the skin.

Hot packs are most effective when they are applied on relatively flat body
surfaces or over large skin areas for approximately 20 minutes.

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Paraffin Baths

• Provide moderate to vigorous doses of heat
• Temperature range sustained between 124 degrees

– 129 degrees F for 20 minutes:

– do not involve utilization of coupling media when skin
is intact

– for minor, superficial abrasions, sterile gauze may be
used to cover wound prior to application of paraffin

• Primarily used over distal body segments such as
the hand or wrist

Paraffin baths can also provide moderate to vigorous doses of heat, but the
temperature range is usually sustained between 124o to 129oF for around
20 minutes.
However, paraffin baths do not involve the utilization of coupling
media when the skin is intact.
If there are minor, superficial abrasions, sterile gauze may be used to
cover the wound prior to the application of the paraffin.
Paraffin baths are primarily used over distal body segments such as the
hand or wrist and are effective in reducing stiffness and pain.

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Contraindications

• Acute inflammation
• Acute edema
• Deep vein thrombophlebitis
• Bleeding tendencies
• Infection
• Primary repair of tendon or ligament
• Advanced cardiac disease
• Semicomatose or impaired mental status

There are several contraindications that are associated with the application
of superficial thermal agents. These include

• acute inflammation,
• acute edema,
• deep vein thrombophlebitis,
• bleeding tendencies,
• infection,
• primary repair of tendon or ligament,
• advanced cardiac disease, and
• semi-comatose or impaired mental status.

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Contraindications

• Prior to using any heat application, a
thorough medical history should be
completed to determine whether a thermal
agent can be applied safely. Medical
history can reveal extent of:

– peripheral vascular disease or impaired
circulation

– pregnancy
– rheumatoid arthritis

Prior to using any heat application, a thorough medical history should be
completed to determine whether a thermal agent can be applied safely.

• For example, a medical history should reveal whether the patient
has a peripheral vascular disease or impaired circulation since
either will compromise the body’s ability to dissipate the heat
and can increase the likelihood of burns.

• Also, if a patient is pregnant, a superficial thermal agent should
not be applied over the uterus, the developing fetus, or the lower
back.

• Furthermore, if the patient has rheumatoid arthritis, a mild or
moderate heat application may be useful to achieve a therapeutic
goal, but vigorous heat doses can actually increase enzyme
activity and may be harmful to the patient.

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Contraindications

• Extreme caution should be taken when there is an
impaired or lost sensation of an extremity

• If patient is unable to sense thermal effect,
individual may experience burning without being
aware of trauma

• Therapist should evaluate skin color, temperature,
sensitivity, dryness, overall integrity, medical
conditions that might affect treatment (such as
psoriasis), and any medications that many impact
the inflammatory process

Extreme caution should be taken when using a thermal agent if a patient
has an impaired or lost sensation of an extremity.

• Since the patient may be unable to sense the thermal effect, there
is the possibility the patient may experience a burn without being
aware of the trauma.

Therefore, the patient should be evaluated for
• skin color,
• temperature,
• sensitivity,
• dryness,
• overall integrity,
• medical conditions that might affect the treatment (such as
psoriasis), and
• for any medications that may impact the inflammatory process.

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Precautions

• Therapist should always be cautious when
applying any thermal agents

• Heat can result in diminished sensation and
compromised circulation

• Circulatory impairment may result if body
cannot offset added heat

Even if there are no identifiable contraindications, therapists should
always be cautious when applying any thermal agents.
Although the benefits of heat come from its localized effects of the
applications and the body’s systemic responses to it, heat can still result in
diminished sensation and compromised circulation.
Since heat is dissipated through circulating blood, a circulatory
impairment may result if the body cannot offset the added heat.

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Precautions

• Monitor patient’s responses throughout the
application of heat modality to address negative
effects immediately

• Heat can result in increased edema to the body
segment, but can be avoided with positioning and
mobilization techniques

• Screen for overt physiological problems
associated with heat applications such as skin
color and respiratory deviations

• Monitor local signs related to overexposure of
heat by identifying petachiae and blistering of
treated area

The therapist should always monitor the patient’s responses throughout the
application of any heat modality since subjective comments related to
negative effects can be addressed immediately.

• For example, heat can result in increased edema to the body
segment, but can be avoided through the use of positioning and
mobilization techniques.

Furthermore, the therapist should screen for overt physiological problems
associated with heat applications such as skin color and respiratory
deviations.
Finally, the therapist should monitor local signs that are related to
overexposure of heat by identifying petachiae and blistering of the treated
area.

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Therapeutic Response

• Therapeutic goals of superficial thermal agents
include:

– decrease of pain
– decrease of stiffness
– improvement in range of motion
– improvement of tendon excursion
– improvement in viscosity of synovial fluid
– increase of blood flow to promote healing
– reduction of muscle guarding or muscle spasms to

encourage relaxation

• Superficial thermal agents should serve as an
adjunctive modality that will prepare patients for
involvement in purposeful occupations

The therapeutic goals of superficial thermal agents include the
• decrease of pain,
• decrease of stiffness,
• improvement in the range of motion,
• improvement of tendon excursion,
• improvement in the viscosity of the synovial fluid,
• increase of blood flow to promote healing, and the
• reduction of muscle guarding or muscle spasms to encourage
relaxation.

In essence, superficial thermal agents should serve as an adjunctive
modality that will prepare patients for involvement in purposeful
occupations.

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Therapeutic Response

• Indications when using superficial thermal
agents include, but are not limited to:

– treatment of stiff joints
– subcutaneous adhesions
– soft tissue contractures
– chronic arthritis
– sub acute and chronic inflammation
– cumulative trauma
– wounds
– neuromas
– sympathetic nervous system disorders

The indications when using superficial thermal agents include, but are not
limited to,

• the treatment of stiff joints,
• subcutaneous adhesions,
• soft tissue contractures,
• chronic arthritis,
• sub-acute and chronic inflammation,
• cumulative trauma,
• wounds,
• neuromas, and
• sympathetic nervous system disorders.

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Therapeutic Response

• Selection of the proper superficial thermal agent
should be based on:

– intervention objective of the heat
– location and surface (contour) area of segment to be treated
– desired dosage (mild, moderate, or vigorous) as well as the overall

tissue temperature
– desired depth of heat penetration
– whether moist or dry heat is preferred method of application
– position of the extremity
– whether active or passive participation by the patient is desirable to

meet intervention outcomes

Since there are different types of superficial thermal agents, the therapist
should select the appropriate modality based on

• the intervention objective of the heat,
• the location and surface (contour) area of the segment that will be

treated,
• the desired dosage (whether mild, moderate, or vigorous) as well as

the overall tissue temperature,
• the desired depth of the heat penetration,
• whether moist or dry heat is the preferred method of application,
• the position of the extremity, and
• whether active or passive participation by the patient is desirable to

meet the intervention outcomes.

34

Hot Packs

• Heat application transmitted through
conduction:

– generally easy to use
– requires minimal maintenance
– very effective up to a depth of one
centimeter
– can elevate subcutaneous soft tissue
temperature nearly 39oF
– can extend to 3 centimeters, but will
not have same therapeutic effect

Hot packs transfer heat through conduction and are the most commonly
used heat modality in clinics.
The thermal application is very effective up to a depth of one centimeter
and can elevate the subcutaneous soft tissue temperature nearly 39oF.
Although heat can extend to a depth of 3 centimeters, it will not have the
same therapeutic effect as lesser depths.

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Hot Packs

• Consist of a silica gel medium covered by a
canvas pouch

• Temperature maintained with hydrocollator that
keeps water bath between 165o and 170oF

• When material has been properly heated,
temperature can be maintained for 30 – 45 minutes

• New hot pack will require 2 hours to achieve
therapeutic affect

• After each application, it will require 30 minutes
to reheat pack before it can again reach a
therapeutic temperature level

Hot packs consist of a silica gel medium covered by a canvas pouch.
The temperature is maintained with a hydrocollator that keeps the water
bath between 165o and 170oF and is high enough to kill any bacteria that
may collect on the canvas pouch.
When the material within the hot pack has been properly heated, the high
temperature rate can be maintained for 30-45 minutes after removing the
pack from the hydrocollator.
Generally, a new hot pack will require two hours to achieve its therapeutic
effect.
After each application, it will require approximately 30 minutes to fully
reheat the pack before it can again reach a therapeutic temperature level.

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Hot Packs

• Direct contact will result in immediate pain and
damage (including burns)

• Coupling medium should be placed between hot
pack and skin:

– use 5 – 6 layers of dry Turkish towels
– towels can create air pockets to serve as added

insulation
– dry towels should be utilized because heat will transfer

faster if the heated towels are damp

• Some clinics use a commercially available terry
cloth covering that provides equivalent of 3 layers
of towels

Since hot packs are heated to a temperature of 170oF, any direct contact
with the skin will result in immediate pain and damage (including burns)
to the soft tissue.

Consequently, a coupling medium should be placed between the hot pack
and skin that consists of 5 to 6 layers of dry Turkish towels.

These towels are also beneficial in creating air pockets that can serve as
added insulation.

When treating a patient, dry towels should always be utilized as the
coupling medium because heat will transfer at a more rapid rate if the
heated towels are damp.

However, if a hot pack cover is repeatedly used throughout the day, its
usefulness will diminish because dampness will gradually develop. Some
clinics use a commercially available terry cloth covering that provides the
equivalent of three layers of towels.

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Hot Packs

• Advantages

– generally easy to use
– require minimal maintenance (with a hydrocollator)
– provide moderate and vigorous doses of heat
– come in various size and shapes
– passive form of treatment since patients are not involved

during application
– incorporate heat treatment into intervention program
– body segment can be placed into sustained positional

stretch

Hot packs are generally easy to use, require minimal maintenance (with a
hydrocollator), provide moderate and vigorous doses of heat depending on
the number of towels used as a coupling medium, and come in various
sizes and shapes that can cover large areas and match the contours of the
body.
They are also considered a “passive” form of treatment since patients are
not actively involved during the application.
Furthermore, the therapist can incorporate the heat treatment into an
intervention program and place the patient’s body segment into a sustained
positional stretch of soft tissue for the entire heating session.

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Hot Packs

• Disadvantages

• After hot pack has been applied, the skin cannot be
observed.

• Patient may not be able to tolerate treatment and
weight

• Weight can accelerate rate of heat being transferred
• Passive treatment may not allow AROM during the

heating period

However, after a hot pack has been applied, the skin cannot be observed
and the heating cycle may need to be interrupted to ascertain whether the
patient is able to tolerate the treatment.
Furthermore, some patients may not be able to endure the weight of the
hot pack and the weight can also accelerate the rate of heat being
transferred from the hot pack to the skin.
Moreover, since it is a passive application, it may not allow any active
motion during the heating period.

40

Hot Packs

• Application procedures:

– define patient’s problem and set intervention goal
– decide whether hot pack is the most appropriate

modality
– outline contraindications and precautions relative to the

patient
– educate patient about the procedure and address any

concerns
– ask patient to remove any jewelry or clothing on area

being treated

The initial application procedures consist of
• defining the patient’s problem and setting the intervention goal,
• deciding whether a hot pack is the most appropriate modality,
• outlining the contraindications and precautions relative to the
patient,
• educating the patient about the procedure and addressing any
concerns, and
• asking the patient to remove any jewelry or clothing on the area
that will be treated.

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Hot Packs

• Application procedures (cont.):

– remove hot pack from Hydrocollator and place it in hot
pack cover (if there is no cover, wrap hot pack in 6 – 8
layers of dry Turkish towels and add extra towels if
they are old or thin)

– apply hot pack to body segment and secure so it will
not shift during the treatment session

– start treatment timer for 20 minutes and advise patient
to immediately indicate if hot pack feels too hot (or
there is a sense of burning)

After the hot pack has been properly heated, it should be removed from
the Hydrocollator and placed in a hot pack cover.
If there is no hot pack cover, the hot pack should be wrapped in 6 to 8
layers of dry Turkish towels.
When the towels are old or thin, extra layers of towel may be added to
achieve the same affect.
Upon applying the hot pack to the body segment, secure it so the hot pack
will not shift during the treatment session.
Then set the treatment timer for 20 minutes and advise the patient to
immediately indicate whenever the hot pack feels too hot (or there is a
sense of burning).

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Hot Packs

• Application procedures (cont.):

– At the end of 5 minutes, check patient’s status:
• ask how treatment felt
• remove hot pack and towels to check skin for signs
of burning, excessive redness or blistering and
discontinue treatment if this occurs
• briefly apply cold pack if there is overheating response

– At the end of 20-minute treatment session:
• remove hot pack and towels
• ask the patient about treatment session
• treated area should appear slightly red and be warm to the touch
• place hot pack in Hydrocollator (reheat for 30 minutes)

At the end of five minutes, check the patient’s status and ask the patient
how the treatment felt.

• Remove the hot pack and towels to check the skin for signs of
burning, excessive redness or blistering.

• If there is evidence of overheating, discontinue treatment
immediately and briefly apply a cold pack to stop the overheating
response.

At the end of the 20-minute treatment session, remove the hot pack and
towels and again ask the patient how the treatment session felt.

When inspecting the skin, the treated area should appear slightly red and
be warm to the touch.

The hot pack should then be placed in the hydroculator and reheated for
30 minutes before using it again.

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Paraffin Baths

• Require special thermostatically controlled tank
that mixes paraffin wax (6 parts) and mineral oil
(one part) at a temperature of approximately 122oF

• Effectively treat distal extremities such as hands
and wrists

• Applied at moderate to vigorous dosages to
decrease stiffness and pain in joints, reduce pain in
soft tissues, and improve range of motion

Paraffin baths are another conduction heat modality commonly used in
many clinics.
This type of application requires a special thermostatically controlled
tank that mixes paraffin wax (six parts) and mineral oil (one part) at a
temperature of approximately 122oF.
The wax mixture can be applied directly to the skin and will effectively
treat the distal extremities such as the hands and wrists.
Paraffin heat treatments can be applied at moderate to vigorous dosages
to decrease stiffness and pain in joints, reduce pain in soft tissues, and
improve range of motion.

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Paraffin Baths

• Application methods:

– dip hand into paraffin tank 10 times:
• wrap in plastic bag and drape with cloth towel
• retains moderate dose of heat

– dip hand 7 times to create wax glove:
• submerge in paraffin bath for 20 minutes
• obtains vigorous dose of heat

– brush/pour 10 coats of paraffin wax onto body segment:
• cover with plastic and drape with towel
• retains moderate dose of heat

There are three ways to apply this treatment modality.
• The first involves dipping the hand into a paraffin tank 10 times
with a short pause between each dip to allow the coating to dry.
After the last dip, the wax-covered hand should be wrapped in
plastic bag and a cloth towel should be draped over the treated
area in order to retain a moderate dose of heat.
• The second method involves dipping the hand 7 times to create a
wax glove and then submerging the hand into a paraffin bath for
20 minutes to obtain a vigorous dose of heat.
• The third method involves using a paint brush to apply paraffin
wax onto a body segment such as an elbow. After brushing on 10
coats to build up a sufficient layer of wax, the treated area should
be covered with plastic and draped with a towel to retain a
moderate dose of heat.

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Paraffin Baths

• Advantages

– easy to apply, efficient, and relatively inexpensive,
especially when treating small joints of the hand

– heat can be distributed evenly, dosage levels can be
adjusted as needed, and mineral oil can lubricate skin

– passive stretch to finger joints can be sustained
throughout heat application when Coban tape is used

– very effective for patients with rheumatoid arthritis
when only moderate amount of heat is applied

Paraffin baths are easy to apply, efficient, and relatively inexpensive,
especially when treating small joints of the hand.
This form of heat can also be distributed evenly, dosage levels can be
adjusted as needed, and the mineral oil in the paraffin mixture can
lubricate the skin.
Furthermore, passive stretch to finger joints can be sustained throughout
the heat application when Coban tape is used.
This is particularly effective for patients with rheumatoid arthritis when
only a moderate amount of heat is applied.

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