Thoracic spine kyphosis >40° (normal 25-40°).

Thoracolumbar spine kyphosis >30° (normal ~zero degrees).

Some disorders affecting the spine and resulting in kyphosis :

• Postural disorders.
• Scheuermann kyphosis.
• Congenital disorders.
• Paralytic disorders (e.g., Poliomyelitis).
• Myelomeningocele.
• Post-traumatic (fractures with/without cord damage).
• Inflammatory (e.g., Tuberculosis)
• Post surgical (e.g., Postlaminectomy)
• Post irradiation.
• Metabolic (e.g.,Osteoporosis).