What characterizes negative bone balance?

• A. Osteocytes are overactive
• B. Osteoblasts are inactive and osteoclasts are overactive
• C. Osteoblasts are active, and resorption is high
• D. Bone formation is greater than resorption

Answer: (B)

Negative bone balance is characterized by a situation in which bone resorption exceeds bone formation. This imbalance often results in a loss of bone density and strength over time, leading to an increased risk of fractures.

In the context of the correct answer, when osteoblasts are inactive, there is a reduced formation of new bone. Osteoclasts, on the other hand, are responsible for bone resorption. When they are overactive, they break down more bone tissue than is replaced by osteoblasts, leading to a net loss of bone material. This is particularly relevant in conditions such as osteoporosis, where bone mass decreases, and the structural integrity of bone is compromised.

The other choices do not accurately reflect the concept of negative bone balance. For instance, if osteocytes were overactive, it would not clearly signal a negative balance since osteocytes primarily maintain bone matrix and do not directly influence the formation versus resorption dynamics in a way that results in negative balance. Additionally, an active osteoblast and high resorption or greater formation than resorption both suggest a positive or neutral bone balance rather than the negative scenario being described.