Women can’t straighten up their backs because of lumbar sprain, lumbar muscle strain, lumbar disc herniation and other factors. 1. Lumbar sprain: due to acute strains of the lumbar muscles caused by bending, turning, and carrying heavy loads, lumbar pain can occur and can’t straighten up the waist. 2. Lumbar muscle strain: also known as lumbar fasciitis, due to trauma, overexertion, exposure to wind and cold, or long-term poor posture (standing, sitting, bending over) and other factors can make the lumbar muscles, ligaments, and other soft tissue damage, lumbar pain, distension, and can not straighten out the waist of the performance. 3. Lumbar disc herniation: the protruding intervertebral disc stimulates or presses the cauda equina nerve or nerve root, which manifests as lumbar pain, sciatica, numbness of the lower limbs, or inability to straighten up after bending over. Women who can not straighten up may also have other reasons, such as recurring low back pain and can not be relieved, we recommend timely medical care, improve the examination to clarify the cause of the disease, to give targeted treatment or treatment.