The way to decide when to use heat versus cold is dependent upon what has happened, when. It would be simpler if the issue were clear, but that is not the case when deciding what to use. Physical therapists, athletic trainers, doctors all have to take the patient as they are, when they show, and deal with the situation at hand. This article is an attempt to help educate the patient on what to use if there is injury or chronic pain.
First is this warning for all patients and health care practicioners:
Hot or Cold Therapy should not be used by individuals who are sensitive to temperature extremes, such as those with circulatory problems, diabetes, nerve damage, paralysis or sensitive skin.
Now having stated the warnings let's figure out what to use, when. First let's talk about the use of cold therapy.
Cold therapy often revolves around the acronym RICE (rest, ice, compression, elevation) and reminds us how to treat injuries, such as sprains, strains, bumps and bruises.
Today you may be familiar with those situations where there is spinal cord or brain injury and one of the first steps is to stop the swelling. Additional swelling actually may cause permanent paralysis in spinal cord injuries. We have found this can be the causative problem of permanent neural cell destruction so the advanced method of treatment is to stop the unnecessary swelling. This is done by advanced chilling methods to decrease the temperature in the injured tissue areas.
A very important point to remember is the use of cold therapy involves settling or calming the inflammatory processes. When one exercises, as one should to increase the elasticity of the injured structures, that this is simply the re-injury of the area. The use of cold is due to the process of re-injury when rehabbing, so the old injury is now not old, but a new injury of much less severity.
Stretching and increasing range of motion is in reality a process of allowing some healing to occur, but then reinjuring to restart healing but with greater range of motion going forward. decide when to use heat versus cold is dependent upon what has happened, when.
Now let's look at warm, moist heat therapy.
Warm, moist therapy: Apply heat to help reduce pain and promote healing once swelling has subsided.
Please note this type of heat is referred to as "warm, moist" heat and not "heat therapy" or "hot therapy". There are so many situations where dry heat is not indicated. In many clinical settings heat thearapy is administered by use of infrared lamps. Infrared lamps are the same heat source we use to keep french fries warm!! This often is not the heat therapy of choice.
Unfortunately even in classic wound care manuals the heat treatments are referenced as the use of "infrared" but this form of dry heat is actually contraindicated and retards healing, rather than assisting in wounds.
The big advantage of warm moist heat is to stop pain. By stopping pain, especially during rehab. exercise programs, one is able to increase range of motion due to lack of pain.
Warm, moist heat should be used during the exercise programs and prior to. The reason for using warm moist heat prior to stretching exercises is the heat increases blood flow which also increases the elasticity of the area where the blood flows to. Increased elasticity is caused by the additional blood flow in the area and the veins are expanded as are the tissues and cells due to the increased capacity due to the increased blood flow.
The heating pad is put over the area to be stretched and there is less pain, greater range of motion and increased tissue elasticity. The restoration of function to an injured area is accelerated when warm moist heat is used in conjunction with and during exercising.
As a general rule once the exercises are finished then it's often good practice to cool down the area with cold therapy to subside the inflammatory effects that occurred during the stretching.
For chronic pain patients, those suffering some form of pain etiology for greater than 3 months, the use of cold or warm moist heat is dependent upon what form of thermal therapy provides the most relief. It is common for chronic pain patients to use combinations of cold and warm moist heat to relieve pain.
If an electrotherapy device is used such as a tens unit or interferential unit then in most situations you want to use warm moist heat actually during the use of the tens or interferential unit. The reason for using warm moist heat during interferential stimulation is the moisture of the pads actually puts water, a conductor of electricity, onto the skin surface and this makes for less resistance and greater penetration.
The 2nd reason is the warm heat increases blood flow to the area and blood is also conductive to electrical stimulation and that adds to better conduction so the pleasant stimulus of the interferential is delivered to the targeted sensory nerves. The combination of warm moist heat and interferential therapy provides much greater carryover pain relief. Pain often returns once the thermal effects wear off but with interferential the carryover can be extended considerably longer, often measured in weeks for the chronic pain patient.