Forma, Vol. 12 (Nos. 3, 4), pp. 235-245, 1997
Original Paper

Measurement of Strain Distributions within Trabecular Bone: Relationships between Architecture and Function

Brian K. Bay, Ph. D.

Orthopaedic Research Laboratories, Department of Orthopaedic Surgery, University of California Davis School of Medicine, Sscramento, CA, 95817, U.S.A.

(Received December 15, 1995; Accepted November 11, 1996)

Keywords: Trabecular Bone, Strain, Homogenization, Properties, Trabecular Orientation

Abstract. Trabecular bone is an extremely complex and variable mineralized tissue that plays important structural roles in the human skeleton. Understanding the mechanics of trabecular bone is essential to the study of many important orthopaedic diseases, including osteoporosis and osteoarthritis. One of the major impediments to the understanding of trabecular bone mechanics has been the lack of direct experimental data on strain. Progress in this regard has been achieved through the development of a digital image correlation technique for the measurement of two-dimensional continuum level strains at high spatial resolution within samples of trabecular bone. The technique is briefly described, and the precision of displacement measurement and strain calculation is discussed. Two basic problems relevant to trabecular bone mechanics are then evaluated: 1) the relationship between localized and homogenized strains; and 2) the relationship between trabecular orientation and functional strains.