Cancellous bone

Cancellous bone, synonymous with trabecular bone or spongy bone, is one of two types of osseous tissue that form bones. The other osseous tissue type is cortical bone also called compact bone.

Characteristics

Cancellous bone has a higher surface area to mass ratio than cortical bone because it is less dense. This gives it softer, weaker, and more flexible characteristics. The greater surface area in comparison with cortical bone makes cancellous bone suitable for metabolic activity e.g. exchange of calcium ions. Cancellous bone is typically found at the ends of long bones, proximal to joints and within the interior of vertebrae. Cancellous bone is highly vascular and frequently contains red bone marrow where haematopoiesis, the production of blood cells, occurs. The primary anatomical and functional unit of cancellous bone is the trabecula. It is commonly thought that the trabecula within the cancellous bone is aligned towards the mechanical load distribution that a bone experiences and this has been studied in the vertebral pedicle.^[1]

Its Latin name is substantia spongiosa or substantia spongiosa ossium. The words cancellous and trabecular refer to the tiny lattice-shaped units that form the tissue. It was first illustrated accurately in the engravings of Crisóstomo Martinez.^[2]

Clinical significance

In osteoporosis (specifically Type 1, aka post-menopausal), cancellous bone is more severely affected than cortical bone.

References

• Netter, Frank H. (1987), Musculoskeletal system: anatomy, physiology, and metabolic disorders. Summit, New Jersey: Ciba-Geigy Corporation ISBN 0-914168-88-6

External links

• Histology image: 02601lba – Histology Learning System at Boston University - "Cartilage and Bone and Bone Histogenesis: trabecular, woven and lamellar bone"
• "Fractal Analysis of Trabecular Bone". University of Washington. Retrieved October 2010.