Possible causes of spinal pain when bending over include muscle strain, myofasciitis, spinal stenosis, and herniated disc. 1. Muscle strain: It may be caused by muscle strain in the posterior lumbar region. In the process of bending, due to muscle contraction, it is easy to produce the symptoms of spinal pain. 2. Myofasciitis: it may be caused by myofasciitis in the lower back, and the inflammation stimulation will easily trigger the symptoms of local pain. When the patient bends over, the fascia is stretched, resulting in localized tension and spasm, which triggers the manifestation of spinal pain. 3. Spinal stenosis: It may be caused by spinal stenosis, which easily triggers the symptoms of spinal pain. When bending over, the spine will be squeezed, which will aggravate the symptoms of spinal pain. 4. Herniated disc: This may be caused by a herniated disc. In the process of bending over, due to the increase in local pressure, it is easy to cause the herniated disc to compress the surrounding tissues, thus triggering the symptoms of spinal pain. Spinal pain when bending may also have other reasons, it is recommended to go to the regular hospital in time to improve the relevant examination, clear the cause of the disease, under the guidance of the doctor for targeted treatment or treatment.