Causes

The individual bones (vertebrae) that make up a healthy spine look like cylinders stacked in a column. Kyphosis occurs when the vertebrae in the upper back become more wedge shaped.

Abnormal vertebrae can be caused by:

• Fractures. Broken or crushed vertebrae (compression fractures) can result in curvature of the spine. Mild compression fractures often don't produce noticeable signs or symptoms.
• Osteoporosis. This bone-thinning disorder can cause spinal curvature, especially if weakened vertebrae result in compression fractures. Osteoporosis is most common in older women and people who have taken corticosteroids for long periods of time.
• Disk degeneration. Soft, circular disks act as cushions between spinal vertebrae. With age, these disks dry out and shrink, which often worsens kyphosis.
• Scheuermann's disease. Also called Scheuermann's kyphosis, this disease typically begins during the growth spurt that occurs before puberty. Boys are affected more often than girls.
• Birth defects. Spinal bones that don't develop properly before birth can cause kyphosis.
• Syndromes. Kyphosis in children can also be associated with certain syndromes, such as Ehlers-Danlos syndrome and Marfan syndrome.
• Cancer and cancer treatments. Cancer in the spine can weaken vertebrae and make them more prone to compression fractures, as can chemotherapy and radiation cancer treatments.