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Physical Therapy

The modalities of physical therapy, Physical therapy and the aging adult

Physical therapy is a medical specialty that provides treatment using various devices or the hands to strengthen muscles and supply flexibility to a part of the body that is subnormal. The need for physical therapy can be the result of a genetic condition, disease, surgery, or a trauma such as a burn or automobile accident. The goal of physical therapy is not necessarily to restore normality but to allow the patient to return to a comfortable and productive life even if the problem persists.

This exacting science has evolved from centuries of using natural therapeutic methods such as sunlight, warm springs, and warm mud to treat injuries. The modern form of physical therapy bloomed after World War I when wounded soldiers were in great need of such services. Further incentive was provided by World War II, and the epidemic of poliomyelitis in the mid-1950s again brought on great numbers of patients in need of therapy. The development of antibiotics and other modern therapeutic measures preserved the lives of those who earlier would have died. These wounded, limbless, or diseased individuals needed a means to regain their independence and ability to earn a living.

Modern physical therapists use heat and cold, electricity, massage, and various types of machines designed to assist flexibility or restore strength to a given body part. Efforts must go far beyond the simple exercising or heating of an injured limb, however. Most physical therapy is carried out by a team headed by a physiatrist, a physician who specializes in the application of various means of physical therapy. The physical therapist, a technician who is schooled in the muscles and joints and how to exercise them, carries out the exercise program with the patient. Devices that apply pressure in certain directions and on which resistance can be adjusted are employed in the exercise program, as is simpler methodology such as walking or running. An engineer can build special equipment as needed or alter existing machinery to better suit the patient's needs. The rehabilitation nurse provides basic medical care and tracks the patient's progress. If needed, a psychologist is brought in to help the patient adjust to a new, less-comfortable lifestyle. An occupational therapist can assess the patient's needs and provide instruction on how to move about his home, use prosthetic devices, and specially constructed assist devices such as doorknobs or fork handles that allow someone with a paralyzed hand to open doors or feed himself.

Four basic modalities are employed in physical therapy, each applied where and when it will do the most good. Not all of the modalities are used in every case.

Cold therapy

Cold therapy or cryotherapy is an effective means of reducing inflammation following an accident or injury. Cold therapy is applied in the form of ice packs, sometimes combined with massage, cold water bath of the injured area, and other methods. The reduced temperature will quell the firing of the nerve-muscle units and reduce muscle spasms, and that along with the anesthetic effect of the cold temperature will ease pain. Also, the cold reduces blood flow into the injury and reduces any bleeding that may be present and reduces oxygen demands of the injured tissue, thus preserving the muscle cells. An ice pack often is applied with a compression wrap to reduce swelling, and with elevation of the injured extremity above heart level for maximal reduction in swelling.

Heat therapy

Heat or thermotherapy may be employed only after the active swelling of the injury has abated, 24-48 hours following the injury. Heat is conveyed into the injured area by the use of moist heat packs, hot paraffin, hot air or hot water as in a whirlpool bath, by infrared lamp, and by conversion. Conversion is the development of heat brought about by the passage of sound waves or electric current through tissue. Diathermy is an example of electrical waves directed into tissue and converted into heat. Ultrasound, very high-frequency sound waves, bring about the vibration of the tissues, which increases the temperature within them. A form of application of sound waves called phonophoresis consists of application of a medication to the injured area followed by ultrasound to drive the medication deep into the tissues.

Heat increases blood flow to an area, so should not be used when internal bleeding accompanies an injury. However, like cryotherapy, heat reduces muscle spasms by increasing the blood flow to an area, which helps to wash out metabolic waste products and increase the amount of oxygen reaching the tissues.

Electrical stimulation

Application of electrical stimulation can restore muscle tone by stimulating muscles to contract rhythmically. This method is used often when an injured person has been confined to bed for a long period of time. Over time, muscles will atrophy and the patient will require long, arduous periods of exercise once he is mobile. The use of electrical stimulation can prevent muscle atrophy and reduce the necessary physical therapy regimen required later. Electricity is also used to drive molecules of medication through the skin into the tissues. This is called iontophoresis. A special machine called a TENS machine (transcutaneous electrical nerve stimulation) beams electric current through the skin (transcutaneously) into the injured area specifically to stop pain. Why TENS has this ability to assuage pain remains open to question, but it is thought that it prevents pain perception by the sensory nerves in the injured area. That is, the nerves that normally would detect pain and carry the impulse to the spinal cord do not sense pain. The electrical signal from the TENS machine can be adjusted for frequency and strength to achieve its effect without patient discomfort. All electrical stimulation is delivered by placing pads on or around the injured area to conduct the electrical current.

Mechanical manipulation

The use of massage, manipulation of the injured limb, traction, and weight lifting are part of the mechanical form of physical therapy. Massage is the rubbing, tapping, or kneading of an injured area to increase blood circulation and relieve pain. Manipulation consists of putting an injured joint through its movements from one extreme to the other. This is designed to restore full range of motion to the joint and eliminate pain from movement. Traction is the application of weight to stretch muscles or to help increase the space between vertebrae and relieve nerve compression. Manipulation may be carried out by a trained technician or by using a machine especially constructed to exercise the injured joint. Resistance can be altered in the machine to make joint extension or flexing more difficult, thus helping to build the muscles that control the joint movement.

Many forms of physical therapy can be carried out at home, but the exercises must first be carefully explained by a trained therapist. Incorrect application of a physical therapy modality can be as harmful as any traumatic injury. Most modalities are applied two or three times daily over a period of time to help restore movement, flexibility, or strength to an injured area.

Aging is a normal process. Some age-related bodily changes may be misunderstood and unnecessarily limit daily activities. Normal aging need not result in pain and decrease in physical mobility. A physical therapist is a source of information to understand these changes and offer assistance for regaining lost abilities or develop new ones. A physical therapist working with older adults understands the anatomical and physiological changes that occur with normal aging. The physical therapist will evaluate and develop a specially designed therapeutic exercise program. Physical therapy intervention may prevent life long disability and restore the highest level of functioning.

Through the use of tests, evaluations, exercises, treatments with modalities, screening programs, as well as educational information, physical therapists:

  • increase, restore or maintain range of motion, physical strength, flexibility, coordination, balance and endurance
  • recommend adaptations to make the home accessible and safe
  • teach positioning, transfers, and walking skills to promote maximum function and independence within an individual's capability
  • increase overall fitness through exercise programs
  • prevent further decline in functional abilities through education, energy conservation techniques, joint protection, and use of assistive devices to promote independence
  • improve sensation, joint proprioception and reduce pain

Common Conditions

A vast number of conditions are treated effectively with physical therapy intervention. Examples of specific diseases and conditions that may be improved with physical therapy include:

  • arthritis
  • sports/orthopedic injuries
  • joint replacements
  • cerebral vascular accident (stroke)
  • coordination and balance disorders
  • Alzheimer disease

See also Syndrome.



Larson, David E., ed. Mayo Clinic Family Health Book. New York: William Morrow, 1996.

Pisetsky, David S., and Susan F. Trien. The Duke University Medical Center Book of Arthritis. New York: Fawcett Columbine, 1992.

Larry Blaser


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—A prefix meaning cold.


—Any of the forms into which physical therapy is divided.


—A prefix meaning heat.


—A term meaning through the skin.

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