Kyphosis is an excessive outward curvature of the top of the spine, causing a hump to appear on the upper back. Hunchbacks suffer from kyphosis or scoliosis (a lateral curvature), or a combination of the two, kyphoscoliosis. The body may compensate for kyphosis by developing a lordosis, or inward curvature, in another part of the spine.
Kyphosis may be simply the result of bad posture or muscle weakness, or the body's way of compensating for another condition such as a hip deformity. A common cause of kyphosis in the elderly is osteoporosis, bone brittleness which leads to collapse of the vertebrae. Other medical conditions which affect the bones, like ankylosing spondylitis, may result in the development of kyphosis. Physiotherapy is an appropriate treatment for some cases of kyphosis, but if it is severe, the wearing of a dreaded back brace, or even a surgical operation on the bones (osteotomy), may be required.