![]() | This article needs more reliable medical references for verification or relies too heavily on primary sources .(March 2022) | ![]() |
Heat therapy | |
---|---|
ICD-9-CM | 93.34-93.35 |
Heat therapy, also called thermotherapy, is the use of heat in therapy, such as for pain relief and health. It can take the form of a hot cloth, hot water bottle, ultrasound, heating pad, hydrocollator packs, whirlpool baths, cordless FIR heat therapy wraps, and others. It can be beneficial to those with arthritis and stiff muscles and injuries to the deep tissue of the skin. Heat may be an effective self-care treatment for conditions like rheumatoid arthritis. [1]
Heat therapy is most commonly used for rehabilitation purposes. The therapeutic effects of heat include increasing the extensibility of collagen tissues; decreasing joint stiffness; reducing pain; relieving muscle spasms; reducing inflammation, edema, and aids in the post acute phase of healing; and increasing blood flow. The increased blood flow to the affected area provides proteins, nutrients, and oxygen for better healing. [2] There is some evidence to suggest that heat therapy can also aid in the treatment of neurodegenerative diseases like Alzheimer's; as well as for cardiovascular benefits. [3] [4] [5]
Moist heat therapy has been believed to be more effective at warming tissues than dry heat, because water transfers heat more quickly than air. Frequent use of saunas has been linked to a lower risk of vascular disease. [6] [7] [8] [9] [10] [4] Clinical studies do not support the popular belief that moist heat is more effective than dry heat. Moist heat results in the perception that the tissue is heated more deeply. In fact, recent studies indicate that vasodilation, the expansion of the blood capillaries (vessels) to allow more blood flow, is improved with dry heat therapy. Expansion of the blood capillaries is the primary objective of heat therapy. Heat therapy increases the effect on muscles, joints, and soft tissue. Heat is typically applied by placing a warming device on the relevant body part.
Newer breeds of heat therapy devices combine a carbon fiber heater with a cordless rechargeable lithium battery and are built into the specific body wrap (i.e., shoulder wrap or back wrap) for targeted heat therapy. Such devices can be used as alternatives to chemical or plugged-in heating pads, but have not been shown to improve the clinical benefit. All devices primarily provide heat to promote vasodilation.
Infrared radiation is a convenient system to heat parts of our body. It has the advantage over direct contact in that radiation can heat directly the area where the blood capillaries and neuron terminals are. When heat comes from a direct contact source it has to heat the external layer of the skin, and heat is transferred to the deeper layer by conduction. Since heat conduction needs a temperature gradient to proceed, and there is a maximum temperature that can be safely used (around 42 °C), this means lower temperature where warming is needed.
Infrared (IR for short) is the part of the electromagnetic radiation spectrum comprised between 0.78 μm and 1 mm wavelength. It is usually divided into three segments:
IR-A, from 0.78 to 1.4 μm.
IR-B, from 1.4 to 3 μm.
IR-C, from 3 μm to 1 mm.
IR radiation is more useful than the visible radiation for heating our body, because we absorb most of it, compared to a strong reflection of visible light. Penetration depth of infrared radiation in our skin is dependent of wavelength. IR-A is the most penetrating, and reaches some millimeters, IR-B penetrates into the dermis (about 1 mm), and IR-C is mostly absorbed in the external layer of the epidermis (stratum corneum). [11] For this reason the infrared lamps used for therapeutic purposes produce mainly IR-A radiation.
Heat creates higher tissue temperatures, which produces vasodilation that increases the supply of oxygen and nutrients and the elimination of carbon dioxide and metabolic waste. [12]
Heat therapy is useful for muscle spasms, myalgia, fibromyalgia, contracture, bursitis. [12]
Moist heat can be used on abscesses to help drain the abscess faster. [13] A study from 2005 showed heat therapy to be effective in treating leishmaniasis, a tropical parasitic skin infection. [14]
Heat therapy is also sometimes used in cancer treatment to augment the effect of chemotherapy or radiotherapy, but it is not enough to kill cancer cells on its own. [15]
Heat therapy has been shown to be beneficial in treating sub-acute and chronic musculoskeletal pain, but the choice to use heat therapy to treat acute musculoskeletal injuries is contraindicated. The duration, frequency, and type of heat application may differ depending on the quality of the pain and the depth of the tissue being targeted. According to a recent article published in the Archives of Physical Medicine and Rehabilitation in 2021, heat therapy, particularly local heat application (LHA), can provide pain relief, reduce muscle stiffness (increasing muscle available range of motion), and improve blood flow through vasodilation to the affected area, thereby promoting healing for chronic musculoskeletal injuries [16]
Heat therapy is contraindicated in case of acute injury and bleeding disorders (because of vasodilation), tissues with a severe lack of sensitivity, scars [12] and in tissues with inadequate vascular supply (because of increased metabolic rate and demand which a tissue with poor blood supply may fail to meet resulting in ischemia). [17]
In the case of chronic musculoskeletal pain, heat therapy can be used to help reduce pain, increase range of motion, and improve flexibility. A longer duration of heat application may be required for more chronic conditions, such as 10 to 30 minutes, two to three times a day. Physical therapy heat modalities that can be utilized to treat chronic conditions include hot packs, paraffin, warm whirlpool, fluidotherapy, and thermal ultrasound. Assessing skin integrity is crucial before and after the application of long durations of heat therapy. Prolonged heat therapy can help promote tissue healing, which can be especially beneficial for chronic conditions including fibromyalgia and low back pain. [16]
The use of Heat therapy for deep-seated tissue can be treated with shortwave, microwave, and ultrasonic waves. This produces a high temperature that penetrates deeper. Shortwave produces a 27 MHz current, microwaves use 915 and 2456 MHz, and ultrasound is an acoustic vibration of 1 MHz. The way ultrasonic waves work is they selectively superimpose the incoming wave and increase the energy for absorption, and the significant part of the longitudinal compression gets converted into shear waves. When they are rapidly absorbed, the interface between soft tissue and bone is selectively heated. [18]
Heat therapy can be used for the treatment of headaches and migraines.[ citation needed ] Many people with chronic headaches also experience tight muscles in their neck and upper back. The application of constant heat to the back/upper back area can help to release the tension associated with headache pain. In order to achieve heat therapy for headaches, many use microwaveable pads[ citation needed ] which can often overheat, potentially leading to injury, and lose their heat after a few minutes. Some new products use heated water, running through pads, to maintain a constant temperature, allowing people with headaches to use hands-free heat therapy in the treatment of their headache pain.[ citation needed ] However no substantial scientific evidence exist for many of these claims.
Thermotherapy increase the extensibility of collagen tissues. Using heat, it can relieve the stiffness in joints in different cases. Shortwave and Microwave heat application may reduce muscle spasms, and selective heating with microwaves can accelerate absorption of hematomas. This will, in turn, allow the stiff muscle to stretch. Ultrasounds are not absorbed significantly in homogenous muscle. Heat therapy using hyperthermia has been used to treat cancer in combination with ionizing radiation. [19]
The immediate use of either dry or moist heat helps with preserving muscle strength and activity. There is also a great deal of pain reduction after the application of moist heat. To decide whether or not to use dry or moist heat, studies show that moist heat has enhanced healing benefits for muscle soreness and can have a positive effect in only 25% of the time of the application of the dry heat. [20] When discussing delayed onset muscle soreness, a myogenic disease that effects the longevity and intensity of muscle soreness, it has been proven that heat can be used to reduce pain if applied within 1 hour of exercise. [21]
Swelling is inevitable when using heating modalities, but many people are unaware of the effect they have on the volume of swelling after application. Studies show that there was an increase in edema immediately after the use of whirlpool treatments more than the use of a moist hot pack. However, 30 minutes later, it was shown that there was no difference in swelling between patients that received either heating modality. This leads us to the conclusion that moist hot packs as well as whirlpool therapy can help decrease edema in distal-radius fractures. [22] According to the available data, heat therapy for lower limb lymphoedema may be beneficial in lowering limb circumference and volume when administered over an extended length of time (1200–3600 min) at a certain skin temperature (39–42 °C) in a controlled setting (lab, hospital, or outpatient). There was no proof that heat therapy was harmful to lymphoedema patients when used within these parameters. As of right now, there is insufficient evidence to support any recommendations for the use of heat therapy for lymphoedema patients in practice. [23]
Heat therapy is shown to be a great modality for women with dysmenorrhea, which is pain during menstruation. NSAIDs are usually the primary treatment for dysmenorrhea but are associated with adverse effects, such as indigestion, headaches, and drowsiness. Superficial moist heat is a great alternative can help calm abdominal muscle cramps associated with dysmenorrhea without the adverse effects of menstruation. Moist heat can also improve pelvic circulation that further helps reduce pain. [24] Heat therapy is shown to assist women with pain and reduce the duration of the first stage of labor. The first stage of labor is associated with painful contractions of the cervix. Heat therapy can help calm these painful contractions while improving circulation which blocks pain signals to the brain. [25]
A sauna is a room or building designed as a place to experience dry or wet heat sessions, or an establishment with one or more of these facilities. The steam and high heat make the bathers perspire. A thermometer in a sauna is typically used to measure temperature; a hygrometer can be used to measure levels of humidity or steam. Infrared therapy is often referred to as a type of sauna, but according to the Finnish sauna organizations, infrared is not a sauna.
Chronic pain or chronic pain syndrome is a type of pain that is also known by other titles such as gradual burning pain, electrical pain, throbbing pain, and nauseating pain. This type of pain is sometimes confused with acute pain and can last from three months to several years; various diagnostic manuals such as DSM-5 and ICD-11 have proposed several definitions of chronic pain, but the accepted definition is that it is "pain that lasts longer than the expected period of recovery."
Tension headache, stress headache, or tension-type headache (TTH), is the most common type of primary headache. The pain usually radiates from the lower back of the head, the neck, the eyes, or other muscle groups in the body typically affecting both sides of the head. Tension-type headaches account for nearly 90% of all headaches.
Interventional radiology (IR) is a medical specialty that performs various minimally-invasive procedures using medical imaging guidance, such as x-ray fluoroscopy, computed tomography, magnetic resonance imaging, or ultrasound. IR performs both diagnostic and therapeutic procedures through very small incisions or body orifices. Diagnostic IR procedures are those intended to help make a diagnosis or guide further medical treatment, and include image-guided biopsy of a tumor or injection of an imaging contrast agent into a hollow structure, such as a blood vessel or a duct. By contrast, therapeutic IR procedures provide direct treatment—they include catheter-based medicine delivery, medical device placement, and angioplasty of narrowed structures.
Ischemia or ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism. Ischemia is generally caused by problems with blood vessels, with resultant damage to or dysfunction of tissue i.e. hypoxia and microvascular dysfunction. It also implies local hypoxia in a part of a body resulting from constriction.
Near-infrared spectroscopy (NIRS) is a spectroscopic method that uses the near-infrared region of the electromagnetic spectrum. Typical applications include medical and physiological diagnostics and research including blood sugar, pulse oximetry, functional neuroimaging, sports medicine, elite sports training, ergonomics, rehabilitation, neonatal research, brain computer interface, urology, and neurology. There are also applications in other areas as well such as pharmaceutical, food and agrochemical quality control, atmospheric chemistry, combustion research and knowledge.
Cupping therapy is a form of pseudoscience in which a local suction is created on the skin with the application of heated cups. As alternative medicine it is practiced primarily in Asia but also in Eastern Europe, the Middle East, and Latin America. Cupping has been characterized as a pseudoscience and its practice as quackery.
Far infrared (FIR) or long wave refers to a specific range within the infrared spectrum of electromagnetic radiation. It encompasses radiation with wavelengths ranging from 15 μm (micrometers) to 1 mm, which corresponds to a frequency range of approximately 20 THz to 300 GHz. This places far infrared radiation within the CIE IR-B and IR-C bands. The longer wavelengths of the FIR spectrum overlap with a range known as terahertz radiation. Different sources may use different boundaries to define the far infrared range. For instance, astronomers often define it as wavelengths between 25 μm and 350 μm. Infrared photons possess significantly lower energy than photons in the visible light spectrum, with tens to hundreds of times less energy.
Cryotherapy, sometimes known as cold therapy, is the local or general use of low temperatures in medical therapy. Cryotherapy may be used to treat a variety of tissue lesions. The most prominent use of the term refers to the surgical treatment, specifically known as cryosurgery or cryoablation. Cryosurgery is the application of extremely low temperatures to destroy abnormal or diseased tissue and is used most commonly to treat skin conditions.
Manual therapy, or manipulative therapy, is a part of Physiotherapy, it is a physical treatment primarily used by physical therapists, occupational therapists to treat musculoskeletal pain and disability; it mostly includes kneading and manipulation of muscles, joint mobilization and joint manipulation. It is also used by Rolfers, massage therapists, athletic trainers, osteopaths, and physicians.
An infrared sauna uses infrared heaters to emit infrared light experienced as radiant heat which is absorbed by the surface of the skin. Infrared saunas are popular in alternative therapies, where they are claimed to help with a number of medical issues including autism, cancer, and COVID-19, but these claims are entirely pseudoscientific. Traditional saunas differ from infrared saunas in that they heat the body primarily by conduction and convection from the heated air and by radiation of the heated surfaces in the sauna room whereas infrared saunas primarily use just radiation.
A strain is an acute or chronic soft tissue injury that occurs to a muscle, tendon, or both. The equivalent injury to a ligament is a sprain. Generally, the muscle or tendon overstretches and partially tears, under more physical stress than it can withstand, often from a sudden increase in duration, intensity, or frequency of an activity. Strains most commonly occur in the foot, leg, or back. Immediate treatment typically includes four steps abbreviated as R.I.C.E.: rest, ice, compression, elevation.
A chronic wound is a wound that does not heal in an orderly set of stages and in a predictable amount of time the way most wounds do; wounds that do not heal within three months are often considered chronic. Chronic wounds seem to be detained in one or more of the phases of wound healing. For example, chronic wounds often remain in the inflammatory stage for too long. To overcome that stage and jump-start the healing process, a number of factors need to be addressed such as bacterial burden, necrotic tissue, and moisture balance of the whole wound. In acute wounds, there is a precise balance between production and degradation of molecules such as collagen; in chronic wounds this balance is lost and degradation plays too large a role.
Cold compression therapy, also known as hilotherapy, combines two of the principles of rest, ice, compression, elevation to reduce pain and swelling from a sports or activity injury to soft tissues and is recommended by orthopedic surgeons following surgery. The therapy is especially useful for sprains, strains, pulled muscles and pulled ligaments.
Neck pain, also known as cervicalgia, is a common problem, with two-thirds of the population having neck pain at some point in their lives.
Contrast bath therapy is a form of treatment where a limb or the entire body is immersed in hot water followed by the immediate immersion of the limb or body in cold ice water. This procedure is repeated several times, alternating hot and cold. The only evidence of benefit is anecdotal and no plausible mechanism has been confirmed.
Hyperthermia therapy(or hyperthermia, or thermotherapy) is a type of medical treatment in which body tissue is exposed to temperatures above body temperature, in the region of 40–45 °C (104–113 °F). Hyperthermia is usually applied as an adjuvant to radiotherapy or chemotherapy, to which it works as a sensitizer, in an effort to treat cancer.
Heat illness is a spectrum of disorders due to increased body temperature. It can be caused by either environmental conditions or by exertion. It includes minor conditions such as heat cramps, heat syncope, and heat exhaustion as well as the more severe condition known as heat stroke. It can affect any or all anatomical systems. Heat illnesses include: heat stroke, heat exhaustion, heat syncope, heat edema, heat cramps, heat rash, heat tetany.
Low-level laser therapy (LLLT), cold laser therapy, photobiomodulation (PBM) or red light therapy is a form of medicine that applies low-level (low-power) lasers or light-emitting diodes (LEDs) to the surface of the body. Whereas high-power lasers are used in laser medicine to cut or destroy tissue, it is claimed that application of low-power lasers relieves pain or stimulates and enhances cell function. The effects appear to be limited to a specified set of wavelengths and new research has demonstrated effectiveness at myopia control. Several such devices are cleared by the United States Food and Drug Administration (FDA), and research shows potential for treating a range of medical problems including rheumatoid arthritis and oral mucositis.
Dentomandibular sensorimotor dysfunction (DMSD) is a medical condition involving the mandible, upper three cervical (neck) vertebrae, and the surrounding muscle and nerve areas.