The ability to maintain a bent posture is due to the lumbar muscles, lumbar ligaments and lumbar intervertebral joints to keep the lumbar spine in a forward leaning position. When bending, the lumbar muscles contract, ligaments tighten, and the pressure on the lumbar intervertebral joints increases. If the lumbar spine and lumbar intervertebral soft tissue lesions or injuries, bending will appear after the symptoms of pain. Long-term sitting work, bending work, heavy physical labor, etc., can lead to the occurrence of lumbar muscle strain due to regular and prolonged strain on the lumbar muscles and ligaments. Patients with lumbar muscle and ligament strain have soreness symptoms that occur after prolonged bending over, or after straining, and the symptoms ease or disappear after rest and sleep. Patients with lumbar disc herniation also experience this soreness after bending, but along with the soreness, most patients also feel back pain, numbness and pain in the legs. A small number of patients with occult spina bifida may also experience back pain after bending, but there may not be any discomfort in general.