Understanding How Bones Work
Osteoporosis is a progressive disease that causes the bones to deteriorate and eventually lead to fractures.
The word osteoporosis defines itself. “Osteo” means bone, and “porosis” means the porous bone structure that results from the gradual loss of bone density. Osteoporosis causes the bones to gradually loose bone mass resulting in porous, brittle bones.
The different causes of osteoporosis usually interrupt the bone remodeling process. An interruption in the bone remodeling process causes the bones to become brittle and thin. To understand osteoporosis, you must understand how this process works.
The actual breaking down and rebuilding of bone tissue is performed by two groups of cells called osteoclasts and osteoblasts. Bone remodeling occurs when small amounts of bone are broken down by cells known as osteoclasts. After the bone has been broken down and reabsorbed in the body, cells known as osteoblasts move in to the area and start building new bone. The process where old bone is reabsorbed and new bone is built is called the remodeling process.
- Osteoclasts The first group of cells called osteoclasts is responsible for the destruction of existing bone. They appear at a specific area to break down existing bone. Osteoclasts make pinhead holes in the bone to release calcium into the bloodstream which eventually leads to the break down of the bones. The entire process of the bone removal process is referred to as bone resorption.
- Osteoblasts Osteoblasts are the bone building cells of the body. Osteoblasts place a matrix made up of collagen in the tiny holes left by the osteoclasts. The collagen matrix will begin to go through a hardening process, also known as the mineralization phase. During this phase, calcium and phosphorous mix with the collagen matrix in the form of calcium phosphate crystals. The calcium phosphate during this hardening phase contributes to the density in the bones. The process of building bones during the bone remodeling process is known as the bone formation phase.
Osteoporosis is not a natural part of aging. Due to a loss of bone mass and tissue, bones that were once strong may be unable to endure the stress of a normal activity. Basic activities such as bending, twisting or coughing can cause a fracture. Until recently osteoporosis was thought of as a natural part of aging. But there’s nothing natural about breaking a bone by simply laughing, coughing or sneezing.
Types of osteoporosis:
- Type I, also known as primary osteoporosis occurs in post-menopausal women, and is due to estrogen deficiency.
- Type II, also known as secondary osteoporosis occurs in both men and women, and is due to aging or calcium deficiency. Type II can also be due to certain diseases, medications or surgical procedures that accelerate bone loss.
The consequences of osteoporosis: Each year osteoporosis is responsible for more than 1.5 million fractures. These fractures usually occur in the spine, hip or wrist, but they may occur in other bones as well. Osteoporosis fractures can be debilitating, painful and sometimes can result in death. Only one-third of the people who break a hip ever return to being as active as they were before the fracture.
Prognosis: There is no cure for osteoporosis. However, there are medications available that help stop the break down of current bone and help aid in rebuilding new bone. Bisphosphonates, hormones (hormone replacement therapy “HRT”),selective estrogen receptor modulators (SERMs), calcitonin and teriparatide are all medications used for treating osteoporosis.