What skeletal locations are primarily associated with trabecular bone?

• A. Spine and ribs
• B. Femoral neck and fingers
• C. Ultradistal forearm and calcaneus
• D. Scapula and thoracic spine

Answer: (C)

Trabecular bone, also known as cancellation bone or spongy bone, is predominantly found in areas of the skeleton that are subject to high levels of stress and where flexibility is beneficial. The ultradistal forearm and calcaneus are excellent examples of skeletal locations where trabecular bone is primarily found.

The ultradistal forearm is the area nearest the wrist, and because it bears weight and allows for a range of motion, it contains a significant amount of trabecular bone to manage those physical demands. Similarly, the calcaneus, or heel bone, provides support and absorbs shock during activities such as walking and running, necessitating the presence of trabecular bone to enhance strength and flexibility in these load-bearing areas.

In contrast, while the other locations mentioned (like the spine and ribs) do contain trabecular bone, the primary association of trabecular bone is indeed stronger in the ultradistal forearm and calcaneus due to their functional roles in supporting loads and facilitating movement, which requires both strength and weight reduction.