Cold compresses are applied to the lesion with ice or ice water in a container, which reduces the local temperature and capillary constriction to reduce bleeding and exudation, reduce the stimulation of metabolites on nerves, and reduce pain, whose analgesic mechanism is exactly the opposite of that of hot compresses. Cold compresses have an irreplaceable role in the treatment of acute lumbar injuries. Within 24 to 48 hours after the injury, cold compresses can reduce the amount of blood seepage from the injury and the resulting swelling and pain, which is conducive to the early healing of the injured tissue. The waist skin burns immediately with cold smelting treatment can reduce the local temperature, reduce exudation, reduce the degree of tissue damage, but also with cool water immersion or continuous rinsing. In addition, pharmacies sold in the “good fast”, “Yunnan Baiyao aerosol”, “Li Tong” and other aerosol can also evaporate heat and reduce the local temperature, play a cold therapy role. Cold compresses are suitable for lumbago caused by acute lumbar injury, such as acute lumbar sprain, lumbar soft tissue contusion, lumbar skin burns, etc.. It can also be used for high fever caused by inflammatory disorders of the lumbar region or high fever caused by spinal cord injury. Patients with low back pain should pay attention to the following points when carrying out home cold therapy: 1. cold therapy is limited to patients within 24 to 48 hours after injury; 2. caution for patients with inflammatory skin diseases in the lumbosacral region; 3. caution for women during menstruation and pregnant women in the lumbosacral region; 4. prohibited for those with exposed lumbar muscles, nerves and other tissues.