Lumbar stiffness is commonly caused by the following reasons: First, lumbar muscle strain: it will lead to short-term lumbar stiffness, and the patient will have clinical manifestations of lumbar acidity and lumbar distension, and the lumbar spine activities will also be seriously affected, and the patient will not be able to actively bend over, and the physiological curvature of the lumbar spine will be found to be straightened by taking X-rays. Second, lumbar fracture: it will cause reflex spasm of the lumbar muscles, and the patient will also have clinical manifestations of lumbar stiffness, accompanied by severe pain in the lumbar region and limitation of lumbar vertebral activities, and compression changes of the lumbar vertebral body will be found in the X-ray. Early diagnosis and early treatment can provide satisfactory relief of clinical symptoms such as lumbar stiffness. If the fracture is severe, surgical treatment to restore the stability of the lumbar spine also needs to be considered. Regardless of the cause of lumbar stiffness, the patient should work with lumbar muscle strength training to bring relief from the clinical symptoms of stiffness.