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Treatment of Pain and Inflammation


Alex Moroz

, MD, New York University School of Medicine

Last full review/revision Jun 2017| Content last modified Jul 2017
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Topic Resources

Professional rehabilitation therapists treat pain and inflammation. Such treatment makes movement easier and enables people to participate more fully in rehabilitation. Techniques used include

  • Heat therapy

  • Cold therapy

  • Electrical stimulation

  • Traction

  • Massage

  • Acupuncture

For therapists, whether to use heat or cold therapy is often a personal choice, although cold therapy seems to be more effective for acute pain. When heat therapy and cold therapy are used, caution must be used to avoid burns and cold injuries.

Heat therapy

Heat increases blood flow and makes connective tissue more flexible. It temporarily decreases joint stiffness, pain, and muscle spasms. Heat also helps reduce inflammation and the buildup of fluid in tissues (edema). Heat therapy is used to treat inflammation (including various forms of arthritis), muscle spasm, and injuries such as sprains and strains.

Heat may be applied to the body’s surface or to deep tissues. Hot packs, infrared heat, paraffin (heated wax) baths, and hydrotherapy (agitated warm water) provide surface heat. Heat may be generated in deep tissues by high-frequency sound waves (ultrasound).


Types of Heat Therapy





Heat applied to the body’s surface

Infrared heat

Heat applied with a lamp, usually less than 20 minutes a day

Care needed to avoid burns

Not used in people with a severe heart, liver, or kidney disorder, peripheral vascular disease, or reduced skin sensation

Arthralgia (joint pain)

Arthritis (various forms)

Back pain


Muscle spasm

Myalgia (muscle pain)

Neuralgia (nerve pain)



Tenosynovitis (inflammation of tendons and their covering)

Whiplash injuries

Hot packs

Cotton cloth containers filled with silicate gel, usually warmed in a microwave oven

Can be wrapped in a towel to protect the skin from burns

Same as for infrared heat

Paraffin bath

Dipping in, immersion in, or painting with melted wax

Usually applied to small joints, such as those of the hand, knee, or elbow

Not used for open wounds


Immersion in agitated warm water in a large industrial whirlpool

Enhances wound healing by stimulating blood flow and helping clean out burns and wounds

Relaxes muscles and relieves pain

Heat applied to deep tissues


High-frequency sound waves to penetrate deep into tissues, vibrating them and producing heat, which draws blood (with oxygen and nutrients) to the area

Not applied to tissues whose blood supply has been reduced (ischemia), numbed or actively infected areas, bones that are healing, or certain parts of the body (such as the eyes, brain, spinal cord, ears, heart, or reproductive organs)

Not used in people with a tendency to bleed or cancer

Bone injuries


Complex regional pain syndrome




Cold therapy (cryotherapy)

Applying cold may help numb tissues and relieve muscle spasms, pain due to injuries, and low back pain or inflammation that has recently developed. Cold may be applied using an ice bag, a cold pack, or fluids (such as ethyl chloride) that cool by evaporation. The therapist limits the time and amount of cold exposure to avoid damaging tissues and reducing body temperature (causing hypothermia). Cold is not applied to tissues with a reduced blood supply (for example, when the arteries are narrowed by peripheral arterial disease).

Electrical stimulation

If muscles lack proper nerve input (because of a peripheral nerve injury, spinal cord disorder, or stroke), the muscles quickly waste away (atrophy) and become stiff and contracted (spastic). Electrical stimulation by electrodes placed on the skin causes the muscles to contract, providing a form of exercise that helps prevent atrophy and spasticity.

One form of electrical stimulation—called transcutaneous electrical nerve stimulation (TENS)—uses low current that does not cause muscles to contract. TENS may be useful for chronic back pain, rheumatoid arthritis, a sprained ankle, shingles, or a localized area of pain. For TENS, a handheld, battery-powered device produces the current, which is applied through electrodes placed on the skin. The device produces a tingling sensation but is not painful.

Transcutaneous electrical nerve stimulation may be applied several times a day for 20 minutes to several hours, depending on the severity of the pain. Often, people can be taught to use the TENS device at home as needed. Most people tolerate the therapy well, but not all people experience pain relief. TENS may cause abnormal heart rhythms (arrhythmias). Thus, people who have a severe heart disorder or a pacemaker should not use it. TENS should not be applied to or near the eyes.


Neck (cervical) traction may be used in a hospital, rehabilitation center, or at home to treat chronic neck pain due to degeneration of bones in the neck (cervical spondylosis), a ruptured disk, whiplash injuries, or spasm of the neck muscles (torticollis—see Focal and segmental dystonias). Traction is more effective when people are sitting than when they are lying in bed. A system that uses a motor is usually most effective.

Typically, traction is combined with other physical therapy, including exercises and stretching exercises. Although cervical traction devices are available through consumer catalogues, therapists should select the type of device and determine the amount of weight to be used. People should not use such devices alone. A family member should be available to release the weight gently, which reduces the risk of injury.


Massage may relieve pain, reduce swelling, and help loosen tight (contracted) tissue. Only a licensed massage therapist should use massage to treat an injury. Massage should not be used to treat infections or inflammation due to blood clots (thrombophlebitis).


Some Uses for Massage

  • Amputation

  • Arthritis

  • Bruises

  • Bursitis

  • Cancer (certain types)

  • Cerebral palsy

  • Fibromyalgia

  • Fractures

  • Hemiplegia (paralysis of one side of the body)

  • Joint injuries

  • Low back pain

  • Multiple sclerosis

  • Neuritis

  • Paraplegia

  • Periarthritis

  • Peripheral nerve injuries

  • Quadriplegia

  • Sprains

  • Strains

  • Tight (contracted) tissues


Thin needles are inserted through the skin at specific body sites, often far from the site of pain. The needles may be twirled rapidly and intermittently for a few minutes, or a low electric current is applied through the needles. Acupuncture may stimulate the brain to produce endorphins. Endorphins, produced naturally in the brain, block pain sensations and reduce inflammation. Acupuncture is sometimes used with other treatments to manage recently developed or chronic pain and arthritis. Acupuncture should be done by a certified acupuncturist and with sterile needles.

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