The tightness and heavy falling of the waist after lumbar spine surgery may be caused by preoperative nerve injury that has not yet recovered, postoperative adhesion of nerve tissue, decreased mobility of the lumbar spine, bed rest and other reasons. 1. Neurological factors: If nerve damage has occurred before lumbar spine surgery, it is normal to feel tightness in the waist and a heavy falling sensation after the surgery, because nerve damage recovery is very slow, and the surgery is just to relieve the compression, and cannot repair the nerve fundamentally. Secondly, some patients need to expose the nerve tissue during lumbar spine surgery, intraoperative tugging and postoperative exudation may cause adhesion of the nerve tissue, which will also be manifested in the above symptoms. 2. Surgical methods and bed rest: some patients undergoing lumbar spine surgery need to undergo fusion of vertebrae, and after fusion, the mobility of vertebrae will be reduced compared to the preoperative period, and the lumbar muscles will be stiff, which will be manifested as tightness and a feeling of falling down; patients need to stay in bed after the surgery, or do not undergo early rehabilitation, which will also lead to stiffness, tightness, and even a feeling of falling down in the lumbar muscles. After lumbar spine surgery, there may be other reasons for the tightness and heaviness of the lower back, it is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, and then give targeted treatment or treatment under the guidance of the doctor.