MHS 233 Ground Bone

Compact Bone
(India Ink)

An alternative technique for examining bone is to saw bone into thin wafers and use abrasive surfaces to produce thin "ground" sections. Many structures are easier to identify after staining with a dark dye (India ink for this specimen).

The higher contrast allows open spaces to be seen in greater detail. The more intense staining of osteons compared to interstitial lamellae reflects their lower mineralization (i.e., higher permeability to the dye).

• Osteons (#1,#2,#3) - cylindrical structures that are the structural unit of compact bone. They are arranged parallel to the lines of stress in a bone.
  • Haversian Canals - circular opening at their center.
  • Haversian Lamellae - concentric layers of mineralized matrix that forms most of the osteon.
  • Lacunae - darkly stained, lenticular spaces in the mineralized matrix that contain an osteocyte.
  • Canaliculi - darkly stained, small channels that connect lacunae with each other. Osteocytes share nutrients by extending cellular processes through canaliculi.
• Interstitial Lamellae (#1,#2,#3) - lightly stained remnants from remodeling of bone.
  • Remnants of Osteons - parts of previous osteons, such as Haversian canals or sections of the Haversian lamellae, are often seen within these areas.
  • Canaliculi - relatively few are stained compared to those in osteons.

The structure of an osteon can also be seen in EM 217 Osteon by scanning electron microscopy. An osteocyte inside a lacunae is shown in EM 218 Osteocyte.