The individual bones (vertebrae) that make up a healthy spine look like squares stacked in a column. Kyphosis occurs when the vertebrae in the upper back become more wedge-shaped. This deformity can be caused by a variety of problems, including:

  • Osteoporosis. This bone-thinning disorder can result in crushed vertebrae (compression fractures). Osteoporosis is most common in elderly women and in people who have taken high doses of 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.
  • Cancer and cancer treatments. Cancer in the spine can weaken vertebrae and make them more prone to compression fractures, as can cancer treatments such as chemotherapy and radiation.
  • Scheuermann's disease. The kyphosis associated with Scheuermann's disease, a hereditary disorder, typically begins during the growth spurt that occurs before puberty. Boys are affected more often than are girls.
  • Birth defects. In rare cases, a baby's spinal column doesn't develop properly in the womb, which can result in kyphosis.

An exaggerated curve in the upper spine also can be caused by slouching. Called postural kyphosis, this problem doesn't involve any deformities in the spine. It's most common in teenagers, particularly girls.

Jun. 14, 2012