In winter, the knee is especially cold due to trauma and underlying diseases, need to pay attention to warmth, can be improved by hot compresses and other physical therapy. 1. Trauma history, if the knee has been traumatized or frostbite, resulting in the knee part of the articular cartilage, periosteum and synovial membrane has been damaged, this kind of situation is generally no special intervention method, need to pay attention to warmth, wear knee pads, hot compresses. 2. Suffering from underlying diseases, such as osteoarthritis, cartilage chronic strain, osteophytes and other diseases, which need to be dealt with in a timely manner for the original disease, if necessary, surgical intervention, daily life can be improved through hot compresses, baking and other physiotherapy methods. It is recommended to seek timely medical treatment under the guidance of a professional physician to carry out targeted treatment.