by using radiation (infrared light) or conduction (hot packs,
paraffin, water). Superficial heat is believed to increase
the pain threshold, reduce muscle spasm,
and relieve pain by acting on free nerve endings.
Cold therapy may be applied using a variety of
techniques, including ice packs, ice massage, cold
baths, and vapocoolant sprays. Cold therapy decreases
pain and inflammation by constricting blood
flow in superficial and intraarticular tissues and
slowing nerve conduction.