What are the causes of low back pain (LBP) ?

Causes of low back pain 

• Mechanical (soft-tissue lesion) back pain
• Intervertebral disc lesions (e.g. prolapse, disc degeneration) 
• Facet joint disease (osteoarthritis, psoriatic arthritis) 
• Vertebral fracture
• Axial spondyloarthritis 
• Paget's disease
• Spondylodiscitis
• Bone metastases 
• Spondylolisthesis (pain aggravated by standing or walking)
• Scheuermann's disease
• DISH (diffuse idiopathic skeletal hyperostosis)
• Arachnoiditis (a rare cause resulting from nerve root sheath inflammation in the spinal canal)

[Source: Davidson's principles and practice of medicine 23rd Edition; page 996]