Patients with soreness and swelling in the thighs are commonly caused by the following: first, overstrain and trauma of the muscles: it can lead to spasm and tension of the thigh muscles, accumulation of acidic metabolites in the muscles, and impaired blood circulation, which can have soreness and painful symptoms of the muscles, and accompanied by muscle weakness. Second, lumbar disc herniation, lumbar spinal stenosis and other diseases: can cause nerve compression, early also cause thigh soreness and swelling, and accompanied by limb movement disorders, with the development of the disease, the clinical symptoms of the thigh will aggravate, and even cause intermittent claudication. Third, lower limb vascular disease: such as varicose veins and lower limb artery occlusion, can also lead to leg muscles, tissue metabolic disorders, the patient will have thigh soreness and swelling, lower limb weakness. Patients with sore and swollen thighs should be diagnosed and treated promptly to resolve clinical symptoms as soon as possible to avoid adverse consequences.