Bone's mechanostat: A 2003 update
Article first published online: 3 NOV 2003
Copyright © 2003 Wiley-Liss, Inc.
The Anatomical Record Part A: Discoveries in Molecular, Cellular, and Evolutionary Biology
Volume 275A, Issue 2, pages 1081–1101, December 2003
How to Cite
Frost, H. M. (2003), Bone's mechanostat: A 2003 update. Anat. Rec., 275A: 1081–1101. doi: 10.1002/ar.a.10119
- Issue published online: 3 NOV 2003
- Article first published online: 3 NOV 2003
- Manuscript Accepted: 6 AUG 2003
- Manuscript Received: 15 JUL 2003
- nontraumatic fractures;
- osteogenesis imperfecta;
- bone quality;
The still-evolving mechanostat hypothesis for bones inserts tissue-level realities into the former knowledge gap between bone's organ-level and cell-level realities. It concerns load-bearing bones in postnatal free-living bony vertebrates, physiologic bone loading, and how bones adapt their strength to the mechanical loads on them. Voluntary mechanical usage determines most of the postnatal strength of healthy bones in ways that minimize nontraumatic fractures and create a bone-strength safety factor. The mechanostat hypothesis predicts 32 things that occur, including the gross anatomical bone abnormalities in osteogenesis imperfecta; it distinguishes postnatal situations from baseline conditions at birth; it distinguishes bones that carry typical voluntary loads from bones that have other chief functions; and it distinguishes traumatic from nontraumatic fractures. It provides functional definitions of mechanical bone competence, bone quality, osteopenias, and osteoporoses. It includes permissive hormonal and other effects on bones, a marrow mediator mechanism, some limitations of clinical densitometry, a cause of bone “mass” plateaus during treatment, an “adaptational lag” in some children, and some vibration effects on bones. The mechanostat hypothesis may have analogs in nonosseous skeletal organs as well. Anat Rec Part A 275A:1081–1101, 2003. © 2003 Wiley-Liss, Inc.