Related Experiment Video
Updated: Jun 5, 2026

Trabecular Bone Microarchitecture Evaluation in an Osteoporosis Mouse Model
Published on: September 8, 2023
Bone marrow fat is inversely related to cortical bone in young and old subjects
Tishya A L Wren1, Sandra A Chung, Frederick J Dorey
1Department of Radiology, Childrens Hospital Los Angeles, MS #81, 4650 Sunset Boulevard, Los Angeles, California 90027, USA.
Objective:
Recent studies suggest a close local link between bone marrow adiposity and endosteal bone formation. Using magnetic resonance imaging, we examined whether the relation between the amount of marrow fat and cortical bone is present at multiple sites along the diaphyses of the long bones of young and old males and females.
Design:
The relations between values for cortical bone area and percent marrow fat in each 5-mm section along the midthird of both femoral shafts were determined using magnetic resonance imaging in eight healthy young (aged <25 yr), and nine healthy old (aged >55 yr) men and women.
Results:
Strong inverse correlations were observed between values for cortical bone area and percent marrow fat along the shafts of all 34 femurs; r values between -0.54 to -0.97; all P values = 0.01-0.0001. The strength of this local association was comparable in the young and the elderly and in males and females.
Conclusion:
Our results underscore the strength of the local connections between bone and marrow adiposity. Increasing our understanding of the mechanism for this association could lead to better diagnosis and treatment approaches for osteoporosis.
Related Concept Videos
Bone Disorders
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...
Changes in the Appendicular Skeleton with Age
Initially, the limb buds consist of a core of mesenchyme covered by a layer of ectoderm. The ectoderm at the end of the limb bud thickens to form a narrow crest called the apical ectodermal ridge. This ridge stimulates the underlying...
Compact Bone
Compact bone, also called cortical bone, is the denser, stronger of the two types of bone tissue. It is found under the periosteum and in the diaphyses of long bones, where it provides support and protection. The microscopic structural unit of compact bone is called an osteon, or haversian system. Each osteon is composed of concentric rings of calcified...
Bone as Supporting Connective Tissue
Bone Matrix
Bone, or osseous tissue, is a connective tissue that has a large amount of two different types of matrix material. The organic matrix is similar to the matrix material found in other connective tissues, including some amount of collagen and elastic fibers. This gives strength and flexibility to the tissue. The inorganic matrix consists of mineral salts— mostly calcium salts— that give the...
The Functions of the Skeletal System
Spongy Bone
Spongy bone is more porous, and less dense compared to compact bone. It is composed of concentric lamellae that are arranged irregularly to form the trabecular network. In some bones, the spaces between trabeculae contain red marrow, where...

