NURS 6501: Final Exam: Please contact Assignment Samurai for help with NURS 6501: Final Exam or any other assignment. Email: assignmentsamurai@gmail.com   Which of the following best describes the pathophysiological mechanism of osteoporosis? Group of answer choices

• Increased bone formation due to excessive activity of osteoblasts
• Autoimmune attack on bone marrow cells
• Abnormal deposition of collagen fibers in bone
• Reduced bone mass due to increased osteoclast activity and decreased bone formation

The correct answer is: Reduced bone mass due to increased osteoclast activity and decreased bone formation   Explanation: Osteoporosis is characterized by low bone mass and microarchitectural deterioration, leading to fragility fractures. Its pathophysiology involves:

1. Increased osteoclast activity: Excessive bone resorption.
2. Decreased osteoblast activity: Reduced bone formation (often due to aging, estrogen deficiency, or calcium/vitamin D insufficiency).
3. Imbalance in bone remodeling: Resorption outpaces formation.

Why Not the Others?

• Increased bone formation (osteoblast activity): Occurs in Paget’s disease, not osteoporosis.
• Autoimmune attack on bone marrow: Seen in multiple myeloma or rheumatoid arthritis, not osteoporosis.
• Abnormal collagen deposition: Occurs in osteogenesis imperfecta (brittle bone disease), not typical osteoporosis.

Key Risk Factors:

• Postmenopausal women (estrogen loss → ↑ osteoclasts).
• Aging (↓ osteoblast function).
• Glucocorticoid use (↓ bone formation).

Thus, osteoclast-driven bone loss is the core mechanism.