Sciatica caused by cold, low temperature as well as strain and poor posture can cause pain due to bad stimulation causing inflammatory exudation from the muscles and accumulation of inflammatory substances, which can irritate the sciatic nerve. In this case, the pain caused by stimulation of the sciatic nerve is not too serious, so you can apply heat, rest in bed, curl up the leg and observe the recovery. If it is very serious, attention should be paid to the presence of primary lesions, such as muscle compression, adhesions, and lumbar spine lesions. If there is disc herniation, compression or lumbar spine slippage, spinal stenosis, etc., which stimulates the nerve roots and sciatic nerve, then slight exertion and cold will aggravate the pain of the nerve. In this case, in addition to paying attention to warmth and avoiding bad posture, it is necessary to examine clearly and treat the root cause.