Polymyalgia rheumatica (PMR) is a clinical syndrome characterized by pain in the proximal limbs and trunk. It generally includes the following three key points: onset at age 50 or older; pain and morning stiffness in two of the three susceptible sites of the shoulder girdle, pelvic girdle and neck, lasting for more than 30 minutes and lasting for more than 1 month; plus evidence of systemic reactions such as elevated erythrocyte sedimentation rate exceeding 40 mm/h or 50 mm/h. In addition to giant cell arteritis (GCA), the diagnosis of polymyalgia rheumatica can be excluded if there are other specific diseases such as rheumatoid arthritis, chronic infection, polymyositis or malignant tumors. PMR and GCA are closely related. About 1/4 of PMR eventually develops into GCA, and 40% of GCA may show PMR manifestations. Therefore, some people believe that PMR and GCA are different manifestations of the same disease, that is, PMR is only one of the clinical manifestations of GCA, but some people also propose that they are independent diseases.