Final answer:
Kyphosis is an excessive posterior curvature of the thoracic region and can result from osteoporosis. It is commonly seen in elderly individuals.
Step-by-step explanation:
Excessive posterior curvature of the thoracic region is known as kyphosis. It can result from osteoporosis, which weakens the anterior portions of the upper thoracic vertebrae and causes their collapse. Kyphosis is often seen in elderly individuals and is sometimes referred to as dowager's hump.