Exaggerated curvature of the spine, in the flexion/extension axis. In the thoracic spine, in adolescents, the most common cause of kyphosis is Sheuermann's disease. In the elderly, the most common cause of kyphosis is disc dengeneration. Localised kyphosis may be caused by collapse of one or more thoracic vertebrae which, in the elderly, may be associated with osteoporosis.
A curve in the spine that points to the back of the body. A hunchback is one example of kyphosis. The letter L followed by a number identifies a specific vertebra in the lumbar spine. For example, L3 is the 3rd vertebra in the lumbar spine.L3-4 would refer to the disc between the L3 and L4 vertebrae.