Heat And Cold Therapy - Physical And Complementary Therapies: Arthritis

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Heat and cold therapy

In the 19th and early 20th centuries, wealthy Europeans embraced hydrotherapy (warm baths) and sought cures at exotic spas for real and imagined ailments. Most resorts claimed that the health benefits were from minerals in the water. The therapeutic value actually lay mostly in the water's temperature. Heat raises the pain threshold and relaxes muscles.

Hydrotherapy remains a standard part of the physical therapist's practice, and its techniques can be used at home. A bathtub equipped with water jets or a hot tub can closely duplicate the warm-water massage of whirlpool baths used by professionals. Of course, oversized tubs are expensive luxuries. For most people, the bathtub works nearly as well. A 15–20 minute soak in a warm bath exposes the body to warmth and allows the weight-bearing muscles to relax.

A warm shower can relieve the morning stiffness of ankylosing spondylitis and may help lessen the stiffness caused by other kinds of arthritis. People can upgrade their showers with an adjustable shower-head massager that's inexpensive and easy to install. It should deliver a steady fine spray or a pulsing stream, usually with a few options in between. Therapists also recommend taking a warm shower or bath before exercising to relax joints and muscles. Dress warmly after a shower or bath to prolong the benefit.

A heating pad is another good idea, but keep in mind that moist heat penetrates more deeply. Although you can purchase hot packs and moist/dry heating pads, a homemade hot pack works just as well. Heat a damp folded towel in a microwave oven (usually for about 10–60 seconds, depending on the oven and the towel's thickness) or in an oven set at 300 degrees (for 5–10 minutes — again, this depends on the oven and towel thickness). To prevent burns, always test the heated towel on the inside of your arm before applying to a joint: It should feel comfortably warm, not hot. To be extra safe, wrap the heated, moist towel in a thin, dry one before placing it on the skin.

Sometimes therapists recommend a paraffin bath. You dip your hands or feet into wax melted in an electric appliance that maintains a safe temperature. After the wax hardens, the therapist wraps the treated area in a plastic sheet and blanket to retain the heat. Treatments generally take about 20 minutes, after which the wax is peeled off. Paraffin bath kits are also available for home use, but it's important to talk with your physical therapist for recommendations and cautions before purchasing one, to avoid burning yourself.

Cold has analgesic effects similar to those of heat: An ice pack on the joint relieves pain, especially after an injury. Gel-filled cold packs are inexpensive and available in different sizes and shapes. Keep two or more in the freezer so you'll have cold therapy available instantly. Ice chips in a plastic bag also work well. Cold packs should be applied for 15–20 minutes and can be reapplied hourly or as needed. Coolant sprays, available from pharmacies, may also be used. Cooling is a temporary measure to relieve pain; too much may induce muscle stiffness and painful circulatory disturbances.

Last updated:	September 05, 2008