Lumbar pain when bending over may be caused by lumbar muscle strain, lumbar disc herniation, lumbar vertebral hyperplasia and so on, and you should consult a doctor in time. 1. Lumbar muscle strain: sedentary, long standing and other poor posture will lead to lumbar muscle strain, lumbar superficial tissue lesions, there will be pain when bending over, rest for a period of time after the pain can be relieved. 2. Herniated lumbar intervertebral disc: when patients have herniated lumbar intervertebral discs, local extrusion will occur when bending, which will aggravate the symptoms of herniated lumbar intervertebral discs, press and stimulate the surrounding tissues and nerves, causing lumbago and the inability to bend over. 3. Lumbar spine hyperplasia: patients with lumbar spine hyperplasia, bending will stimulate the surrounding tissues, so that the acute attack of inflammation, lumbago, can not bend. In addition to the above common causes, but also need to be alert to lumbar spine fracture, lumbar spinal stenosis and other diseases may occur, the occurrence of lumbar pain can not bend over, please go to the hospital in a timely manner.