The lack of strength in the knee may be caused by knee joint disease or lumbar spine disease, and the treatment of the lack of strength in the knee caused by these two pathologies is different, as follows: First, caused by knee joint disease: if the knee weakness is caused by knee joint disease, microwave therapy, ultrashort wave therapy can be considered, and the oral administration of celecoxib and so on, which can make the clinical symptoms relieved. If the symptoms are obvious and there are lesions in the joints, arthroscopic minimally invasive surgery can also be considered to confirm the diagnosis and at the same time carry out treatment, such as restoring the flatness of the joint surface, or reducing joint wear and friction. Second, caused by lumbar spine disease: If knee weakness is caused by lumbar spine disease, lumbar traction, lumbar physical therapy, or even surgical treatment to remove the protruding intervertebral discs and widen the narrow lumbar spinal canal, in order to release the nerve compression and restore the strength of the lower limbs. Therefore, the symptoms of knee weakness should be diagnosed and treated in time, and the corresponding treatment methods should be selected according to the different causes of the disease in order to completely alleviate the clinical symptoms.