2Basics of HeatHeat: a term used to describe the energy that matter can store in the form of electronic, atomic, or molecular motion.The great the molecular motion, the greater the heat production
3Basics of ColdCold: in a physical sense is a negative condition, depending on the decrease in the amount of molecular vibration that constitutes heat. The less the molecular motion, the less heat production. Thus, a sensation of cold results.
4Temperature:Temperature is a measure of the average amount kinetic energy possessed by an individual molecule of a body (kinetic theory of heat).Temperature is a measure of sensible heat of cold in a body.Temperature is expressed as Fahrenheit or Centigrade.
5Classification of temperatures: for treatment purposes, are classified as follows:
6Transfer of energy: heat, or the loss of hear, occurs in any of the following ways: Conduction: ContactConvection: movementEvaporation: through liquid-gas transferRadiation: electromagnetic wavesConversion: transfer from one energy type to another
7Factors in heat transfer Cont Conductivity: the power of transmitting heat, electricity or sound. A tissues conductivity is usually dependent on the water content; the higher the water content the better the conductivityMuscle % water and conducts wellBone and skin are 5-16% water and poor conductors
8Factors in heat transfer Cont Resistance: the tissues opposition to the passage of energyExpressed in Ohms.Bone and fat have high resistanceMuscle and Skin low
9CryotherapyUsed to describe the application of cold modalities that have a temperature range between 32° and 65° F
10Cryotherapeutic Benefits To obtain therapeutic benefitsskin temp. must be reduced to 57 °F for optimal decrease in local blood flowskin temp must be reduce to 58°F for analgesiaSkin tempertaure must be reduced to 36°F to produce intra-articular temp. changes in the kneeThe temp of the skin over a joint decreased the temp in a joint proportionally 10° F skin ° F jointAlso remember that temperature is relative!
11Effects of Cold on Application Site VasoconstrictionDecreased Rate of Cell metabolism resulting in a decreased need for oxygenDecreased production of cellular wastesReduction of inflammationDecreased PainDecreased Muscle Spasm
12Systemic Effects of Cold Exposure General vasoconstriction in response to cooling of the posterior hypothalamus (this happens with a .2°F of circulating bloodHeart rate is decreasedRespiration DecreasesShivering and increased muscle toneIf core temperature continues to drop this is the body’s response to increase heatIN GENERSAL THIS DOES NOT OCCUR WITH ICE APPLICATION!
13The Effects of Ice on Injury Response IndicationsAcute injury or InflamAcute or chronic painSmall 1st degree burnsPostsurgical pain and edemaIn conjunction with rehab ex.NeuralgiaAcute or chronic muscle spasmSpastically accompanying CNS disordersContraindicationsCardiac or Resp. involvementUncovered open woundsCirc. InsufficiencyCold AllergyAnesthetic SkinAdvanced DiabetesRaynaud’s Phenomenon
14Raynaud’s PhenomenonA vascular reaction to cold application or stress that results in a white, red, or blue discoloration of the extremities. The fingers and toes are the first to be affected. This is a sympathetic nervous system reflex
15Physiological Effects of Cold: Metabolic Decreased secondary cell deaths by hypoxia (swelling prevents oxygen from reaching cells). The decrease in metabolism allows them to live without as much oxygen.Normal body temperature is 37 ° C.Increase above 45° C (113° F) proteins denature
16Physiological Effects of Cold: Metabolic Reduction of edema through decreased capillary hydrostatic pressure and decreased permeability and osmotic pressureIncrease blood viscosity (make it thicker so it won’t flood the area as quickly)Decrease in chemical mediator effectiveness (they cause vasodilatation)
17Physiological Effects of Cold: Metabolic Decreases below 15 ° C (58 Þ F) a “hunting” response (Lewis 1932) incursHistamine like release yields an increase vasodilatation as a self defense responseArterio-venal anastomoses (artery directly to veins) allow pooling of blood in feet, hands, ears, and lips. May be place of hunting responseDon’t go below 58 ° F and keep time shorter than 30 minutes to be on the safe side
18Physiological Effects of Cold: Pain Local decrease in free nerve ending sensitivityIncreases the threshold for nerve firingSlows synaptic activityAllows disruption of pain-spasm-pain cycle via analgesia
19Physiological effects of cold: Hemodynamic Vasoconstriction from smooth muscle in arteriolesreflex vasoconstriction from A-delta (spinal reflex to preserve body heat)Cold blood hits hypothalamus and may start shivering response if cold enoughA small amount of vasoconstriction gives a 4 fold decrease in blood flow
20Muscle ActivityDecreased muscle spasm by decreasing muscle spindle activity.Intramuscular fibers (muscle spindle) runs parallel to fibers of the muscle. Ia and II run to dorsal horn of spinal cord and respond to stretch. As the muscle contracts the spindle contracts so it remains sensitive. Cold directly decreases the activity in the Ia and II fibers. The lower the temperature, the lower the activity.
21Effects of Immediate Treatment RICE - Rest, Ice, Compression, ElevationServes to counteract the body’s initial response to injuryRest limits scope of original injury by preventing further traumaIce - function is to decrease cell’s metabolism, decrease the need or oxygen and reduce the amount of secondary hypoxic injury by enabling tissues to live on limited oxygen and secondarily reduce painCrushed ice is the ideal form of cold application during initial injury because it produces the most rapid temp. decrease.
22Effects of Ice on Immediate Tx Compression -decreases the pressure gradient between blood vessels and tissue and discourages further leakage from capillaries.Also Encourages Lymphatic drainageCompression TypesCircumferential - provides even pressureCollateral - Pressure on 2 sides (aircast)Focal Compression - U-shaped horseshoe pads
23Effects of Ice on Immediate Tx ElevationDecreases the hydrostatic pressure within the capillary beds to encourage absorption of edema by lymphatic systemThis has the greatest effect at 90° perpendicular to the groundat 45 ° the effect of gravity is 71% comparatively
24Cryokinetics The use of cold in conjunction with movement Used to decrease pain and allow for free motion through the normal ROMResults in more pronounced macrophage reaction, quicker hematoma resolution, increased vascular growth, faster regeneration of muscle and scar tissueInitiated when the underlying soft tissue and bone are intact and the pain is limiting the amount of function
25Penetration depends on many factors: Cold has a longer wavelength than heatLocal temperature gradientTreatment surface area coveredthickness and characteristics of tissue treated (fat is an insulator, tissues with high water content have better heat transfer)
26Slides in Packet for specific review of each Clinical Application Cold PackIce MassageIce ImmersionCryostretchWhirlpoolsSlides in Packet for specific review of each Clinical Application
27Cold Packs Ice Bags, Reusable Cold Pack Instant Cold Back Tx time for all are minutesBecause of lasting effects application should be no less than 2 hours apartFor controlled Cold Therapy Units - may be applied continuously for 24 to 48 hours post acute injury or surgery
28Cold Packs Precautions Indications AC joint and other areas may not be suitable for wet wrapTension of elastic wrap should be enough to provide adequate compression without unwarranted pressureEnsure Circulation w/wrapFrostbite - if had before chance for reoccurrenceover large or superficial nervesIndicationsAcute injury (may use with wet wrap)Acute or Chronic PainPostsurgical Pain and EdemaShape of Body part
29Ice MassageAppropriate for delivering cold tx to small evenly shaped areas.Most effective for muscle spasm, contusion and other minor well-localized areasDuration of tx5-15 minutes or until ice runs outif the purpose is analgesic, then stop when numb
30Ice Massage Indications Precautions Contraindications Subacute inflam or injMuscle strainContusionAcute or chronic painContraindicationsAll other ice contraind.When pressure is not warrantedSuspected FxPrecautionsInjuries where pressure massage may be contraindicated
31Ice Immersion Temp. 50° - 60 ° F Time 10-20 min. Indications Acute Injury or Inflam.Acute or Chronic PainPost surgical painContraindicationsSame as general ContraindicationsAcute injury where gravity is contraindicated
32Cryostretch “Spray and Stretch” vapocoolant Traditionally preformed with ethyl chloride due to its ability to quickly evaporate and cool superficial tissueThis technique is limited to a counterirritantsimply masks the symptoms to allow for a stretch
33Cryostretch Contraindications Precautions Indications Allergy Open woundsPost/surgicalEyesAll other cold contraind & contraind to passive stretchIndicationsTrigger pointsMuscle spasmsDecreased ROMPrecautionsCan cause frostbiteEthyl Chloride is extremely flammableEthyl Chloride is a local anesthetic but if inhaled can become generalIt’s use is based on tradition rather than fact
34Cold Whirlpools Duration of Tx Indications Contraindications 15-20 minutesTemp 50° - 60 ° FIndicationsDecreased ROMCryokineticsSubacute to chronic inflammationPeripheral nerve injuries (avoid extremes)ContraindicationsAcute conditions where water turbulence would further irritate areaGravityPostsuturalSkin ConditionsAll other contraindications