Compact and Trabecular Bone

Unlike the ground bone specimens, the specimens of two small bones on the following slides were decalcified chemically and then mounted and sectioned with a microtome. After staining with H&E all of the cells are readily distinguishable.

• Examine these three specimens and the images below to compare compact and trabecular bone. Bone sample 1 and sample 2  show osteons very well. Sample 3 is mostly trabecular bone, but a small area of compact bone can also be seen. Compare the appearance of the osteons to those you saw in the ground specimen. Identify periosteum, endosteum, Haversian canals, osteocytes, and marrow.

• The rest of the bone tissue present on sample 3 is trabecular bone, and one area of this specimen was undergoing fracture repair. There is much to identify and study on this slide. Locate and carefully study the following structures: periosteum, marrow, osteoblasts and osteoid, osteoclasts, which may be in Howship’s lacunae, and endosteum. Study the image below to help you find some of these structures.
   

Ossification and bone formation.