The application of infrared thermal imaging technology in medical field mainly uses the infrared radiation of human body itself to collect the infrared radiation energy of human body surface, and after a series of photoelectric signal conversion processing, the infrared radiation information of human body surface is finally presented in the form of pseudo-color infrared thermal image. In the diagnosis of painful diseases, such as acute and chronic shoulder and neck pain, cervical and lumbar diseases, myofascial pain syndrome, etc., there are often some inflammatory characteristics that lead to obvious differences in the temperature distribution of the human body in the diseased area. Many studies have found that medical infrared thermography technology has unique diagnostic value. Generally speaking, in pathological medical diagnosis, the accuracy of infrared detection is very high, because the temperature change of human body surface caused by the difference of pathological changes is very subtle.

The temperature of human limbs is mainly determined by the state of blood circulation. When there are vascular diseases, the blood circulation is blocked and the skin temperature is reduced. Such as angiitis obliterans, arterial embolism, aneurysm, etc., usually manifested as lesion.

If the temperature is abnormal, the location and scope of the lesion can be clearly displayed by infrared thermal imager.