What type of bone is characterized as being most responsive to therapies?

• A. Cortical bone
• B. Trabecular bone
• C. Compact bone
• D. Mechanical bone

Answer: (B)

Trabecular bone, often referred to as cancellous or spongy bone, is the type that is most responsive to therapies. This responsiveness is primarily due to its high surface area and metabolic activity compared to other types of bone. Trabecular bone is found more in areas such as the vertebrae, pelvis, and end of long bones, where it plays a critical role in supporting the overall structure of the skeleton and mineral homeostasis.

Therapies aimed at improving bone density, such as pharmacological treatments for osteoporosis, typically target the trabecular bone because it is more rapidly remodeled than cortical bone. This remodelability allows interventions, such as bisphosphonates or hormone therapy, to have a more pronounced effect on increasing bone density in these areas, potentially lowering the risk of fractures.

In contrast, cortical bone is denser and makes up the outer layer of bones, serving as a protective shell that is less metabolically active, thus less responsive to therapeutic interventions compared to trabecular bone. The other options, such as compact and mechanical bone, are not types recognized in the context of responsiveness to therapy in the same way that trabecular bone is, emphasizing the importance of trabecular bone in therapeutic outcomes.