The pathophysiology of Osteoporosis
Osteoporosis is a disease characterized by a decrease in bone mass that occurs when the rate of bone resorption exceeds the rate of bone formation, a common occurrence as the body ages (Betts et al.,2022). This causes the bones to become brittle to the point where even something as simple as bending over can cause the bones to break. This disease is often called a “silent” disease because symptoms usually go unnoticed until you break a bone. A break or fracture can happen in any bone, but it is most common in the bones of femoral head, vertebrae, and wrists. Osteoporosis is more common in women and/or anyone with a family history of the disease. It affects almost 20% (1 in 5) of women aged 50 and over and almost 5% (1 in 20) of men aged 50 and over (CDC, para 3).
This disease affects the bones of the skeletal system. Bone is a dynamic tissue constantly undergoing. These changes occur when old or damaged bone tissue is removed, and new bone tissue is formed. The pathophysiology of osteoporosis involves a disruption in the balance between bone formation and bone resorption, resulting in a loss of bone mass and deterioration. Bone resorption occurs when osteoclasts remove bone by dissolving minerals and breaking down the matrix (Rockville, 2004). This causes an imbalance favoring bone resorption over formation.
Normal Anatomy of the Skeletal System
The bones of the skeletal system provide structural support for the rest of the body, permit movement and locomotion by providing levers for the muscles, protect vital internal organs and structures, provide maintenance of mineral homeostasis and acid-base balance, serve as a reservoir of growth factors and cytokines, and provide the environment for hematopoiesis within the marrow spaces (Clarke B. (2008). There are 206 bones in an adult body.
They are classified into five primary types: long bones, short bones, flat bones, irregular bones, and sesamoid bones (Betts et al.,2022). Each type of bone has unique characteristics and functions. Bone is made of protein, collagen, and minerals, especially calcium. Collagen provides a framework for incorporating minerals, mainly calcium phosphate into the collagen framework. The mineral makes bone hard and strong, while the collagen offers flexibility so the bone can resist breaking (Branch, 2023).
Mechanism of Pathophysiology in Osteoporosis
The pathophysiology of osteoporosis involves multiple factors, including hormonal changes, genetics, age, and poor diet. As our bodies age, we begin to slow down on the production of the sex hormones estrogen and testosterone. A decrease in estrogen levels in women at menopause is one of the most vital risk factors for developing osteoporosis; because of this, women are more at risk for developing this disease. Between the age of 45-50, women will enter menopause. Menopause occurs when the menstrual period ceases, thus slowing down the production of estrogen. Estrogen is a steroid hormone associated with the female reproductive organs and is responsible for developing female sexual characteristics (Delgado, 2003). Estrogen also plays a crucial role in bone metabolism, particularly in maintaining bone density and strength. It promotes osteoblastic activity and the production of bone matrix; osteoblasts are the cells responsible for forming new bones. (Betts et al.,2022).
Genetics is another factor that contributes to the development of osteoporosis. It can affect anyone, but it is most common in women. According to the National Library of medicine, people who are slim and thin boned
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