Cryotherapy is the local or general use of low temperatures in medical therapy or the removal of heat from a body part. Its goal is to decrease cellular metabolism, increase cellular survival, decrease inflammation, decrease pain and spasm, promote vasoconstriction, and when using extreme temperatures, to destroy cells by crystalizing the cytosol. The most prominent use of the term refers to the surgical treatment, specifically known as cryosurgery. Other therapies that use the term are cryogenic chamber therapy and ice pack therapy. The term "cryotherapy" comes from the Greek cryo (κρυο) meaning cold and the word therapy (θεραπεια) meaning cure.
See main article: Cryosurgery. Cryosurgery is the application of extreme cold to destroy abnormal or diseased tissue. Cryotherapy is used to treat a number of diseases and disorders, especially skin conditions like warts, moles, skin tags and solar keratoses. Liquid nitrogen is usually used to freeze the tissues at the cellular level. The procedure is used often because of its efficacy and low rates of side effects.
Ice pack therapy is a treatment of cold temperatures to an injured area of the body. An ice pack is placed over an injured area and is intended to absorb heat of a closed traumatic or edematous injury by using conduction to transfer thermal energy. The physiologic effects of cold application include immediate vasoconstriction with reflexive vasodilation, decreased local metabolism and enzymatic activity, and decreased oxygen demand. Cold decreases muscle spindle fiber activity and slows nerve conduction velocity, therefore it is often used to decrease spasticity and muscle guarding. It is commonly used to alleviate the pain of minor injuries.
Cryogenic chamber therapy is a treatment whereby the patient is placed in a cryogenic chamber for a short duration (i.e. no more than three minutes, which is comparable to ice swimming), and if used properly, will not destroy tissue. Whole body cryotherapy initially originated in Japan in 1978. However, it was a group of Polish scientists who took the idea and made whole body cryotherapy the physical therapy it is today. The Olympic rehabilitation centre in Spala, Poland opened in May 2000 and has been used as a training and injury rehabilitation centre for many sporting bodies.
The chamber is cooled, typically with liquid nitrogen, to a temperature of - 110 C. The patient is protected from acute frostbite with socks, gloves and mouth and ear protection, but in addition to that, wears nothing but a bathing suit. The patient spends a few minutes in the chamber. During treatment the average skin temperature drops to 12 C, while the coldest skin temperature can be 5 C. The core body temperature remains unchanged during the treatment, however it may drop slightly afterwards. Therapy triggers the release of endorphines which induce analgesia (immediate pain relief).
Patients report that the experience is invigorating and improves a variety of conditions such as psychological stress, insomnia, rheumatism, muscle and joint pain, fibromyalgia, itching, and psoriasis. The immediate effect of skin cooling and analgesia lasts for 5 minutes, but the release of endorphines can have a lasting effect, where the pains and signs of inflammation as found in blood tests remain suppressed for weeks. The effects of extreme cold and endorphine release are scientifically studied. Curiously, some patients compare the feeling to sauna at +110 C.