The 70-year-old man’s waist is severely bent and his legs are numb and weak may be caused by osteoporosis, lumbar disc herniation and so on. It can be treated by taking calcium, analgesic drugs, neurotrophic drugs and other methods. 1. Osteoporosis: due to osteoporosis in the elderly, minor trauma can cause fracture, so that the vertebral body compression, resulting in 70-year-old old man waist severely bent. The bending will make changes to the intervertebral discs, muscles and ligaments, leading to compression of the nerves, which will lead to numbness and weakness of the legs. Calcium carbonate, calcium lactate, calcium citrate, calcium gluconate and other calcium drugs can be taken to treat osteoporosis and relieve the symptoms of severe lumbar curvature and leg numbness and weakness. 2. lumbar disc herniation: 70 year old man waist serious bending leg numbness and weakness may be lumbar disc herniation, lumbar spinal stenosis caused by nerve compression of the leg. 70 year old man, generally conservative treatment, can take celecoxib, diclofenac and other analgesic drugs to relieve the pain, and at the same time oral methylcobalamin neurotrophic drugs to alleviate the symptoms of numbness and weakness of the leg. The 70-year-old man with a severely bent waist and numbness and weakness of the legs, should be timely to the hospital, clear cause and targeted treatment, the use of drugs need to be under the guidance of a doctor.