The inability to bend after lumbar spine surgery may be due to a variety of factors such as short postoperative time, surgical approach, type of trauma, and postoperative stiffness. 1. Postoperative time, surgical methods: the purpose of lumbar spine surgery is to increase the stability of the vertebral body through internal fixation, bone cement, autologous bone or allogeneic bone grafting, within 3 months is to keep the spine in a relatively stable state, and the inability to bend the waist is a normal phenomenon. In addition, if the surgical procedure chosen is vertebral fusion, the surgery itself is to sacrifice the mobility of the vertebrae to restore some of the functions of the spine, and may also be unable to bend. 2. Trauma, postoperative stiffness: If the preoperative injury is more serious, more segments are involved, and more segments need to be immobilized, postoperative stiffness is an inevitable result, and later on the spine needs to be relieved through rehabilitation to compensate for the loss of spinal function. After surgery, the original anatomical structure of the patient has been destroyed, there will be varying degrees of tissue adhesion, muscle stiffness, etc., which may also result in the inability to bend the waist. Lumbar spine surgery may also have other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.