Objectives By the end of this lecture the students will be able to i dentify & explain The concept of cryotherapy Physiological effects Indications & contraindications
What is Cryotherapy
By definition Cryotherapy is the local or general use of low temperatures in medical therapy or the removal of heat from a body part
Cryotherapy facts Cold therapy is one of the most popular methods when it comes to the first aid treatment of some injuries
Cryotherapy Facts Nowadays, local cold application may be applied by the use of various forms of ice or frozen gel packs, Often skin temperature is reduced to 10 C°.
Physical Principles When ice is applied to the skin heat is conducted from the skin to the ice in order to melt it.
Physical Principles The ice requires considerable energy to rise the temperature of 1 g of ice at 0°C to 1 g of water at 37°C requires 491 J. Whereas to rise 1 g of water at 0°C to 37°C requires only 115J
Physical Principles Consequently when trying to cool tissues it is important to use ice during treatment and not just cold water
Physiological Effects of Cold Application Physiological effects of Cryothrapy Circulatory Response Neural response Excitatory Cold Mechanism
Question What is Excitatory Cold Mechanism?
Excitatory Cold Mechanism When cold is applied in an appropriate way on the skin, it increase the excitatory bias around the anterior horn cell
Excitatory Cold Mechanism This can often produce contraction of an inhibited muscle (only with intact peripheral nerve supply).
Excitatory Cold Mechanism This effect can be used when muscle are inhibited postoperatively or in the later stages of regeneration of a mixed peripheral nerve
Circulatory Response The initial skin reaction to cooling is an attempt to preserve heat. It is accomplished by an initial vasoconstriction. This haemostatic response has the effect of cooling of the body part
Circulatory Response After a short period of time vasodilatation follows with alternating periods of constriction and dilatation this is called the “Lewis’s Hunting Reaction”.
Circulatory Response During the vasodilatation, the arteriovenous anastomosis is closed, thus causing an increase blood flow through the capillaries. This is beneficial in the treatment of swelling and tissue damage
Circulatory Response The reduced metabolic rate of cooled tissues allows cooled muscle to contract many more times before fatigue sets in
Neural response The skin contains primary thermal receptors. Cold receptors are several times more numerous than warm receptors
Neural response The rate of conduction of nerve fibers in a mixed (motor and sensory) peripheral nerve is reduced by cooling.
Question Does ice therapy application cause motor nerve paralysis?
Indications Pain Muscle spasm. Swelling.Spasticity. Provide excitatory stimulus to inhibited muscles. Promote repair of the damaged tissues.
Techniques of Application of Cryotherapy The way which ice is applied will vary according to the required effects. It may be applied in the following ways: Ice Packs Commercial Cold packs Immersion Ice cube massage
Techniques of Application of Cryotherapy Excitatory cold ( quick ice) Ice spray
Ice packs There are many kinds of chemical cold packs available for first aid kits, To make an ice pack with items from home, you'll need: ice a sealable plastic bag a towel or pillow case
Ice packs Never place ice directly on skin. Ice can cause frostbite if left on skin for very long. Regardless what you put between the ice and the victim's skin, do not leave the ice on the skin longer than 20 minutes
Commercial Cold packs
These are basically plastic bags filled with a mixture of water and some substance silica gels are the most common Wet towel should be placed between the skin and the pack to avoid excessive cooling
Immersion immersion involves placing the part to be treated in water ranging in temperature from cool to icy. Appropriate for treatment of an extremity or large body areas
Immersion Cold water immersion is ideally used following a heavy weights session, between training sessions or after muscle injury resulting in soreness or bruising
Example 1 minute plunge- (try to relax as much a possible), 2 minutes out of water (air temperature), Repeat 5 times. When very brave, 5 minutes straight
Ice cube massage Used for two distinct reasons 1. counter-irritant action 2. Muscle stimulation
Ice cube massage For the relive of pain ice block is moved over the part using a slow circular massage For neurological facilitation the ice should be applied only briefly
Evaporating sprays Spraying a rapidly evaporating liquid on the skin has the effects of cooling the surface. The liquid is sprayed on to the area to be cooled in a series of short strokes of 5 s each
Evaporating sprays The nozzle of the spray is held about 45 cm from the skin. Cooling from such sprays not lasts very long