Answer the following question given this paragraph: 

Osteoporosis is a common age-related bone disease in which bone density and strength is decreased. Watch this video (http://openstaxcollege. org/l/osteoporosis) to get a better understanding of how thoracic vertebrae may become weakened and may fracture due to this disease. How may vertebral osteoporosis contribute to kyphosis?.


Q: A common age-related bone disease in which bone density and strength is decreased is know as what?


A:
osteoporosis