Using digital image correlation to determine bone surface strains during loading and after adaptation of the mouse tibia

• Published in: Journal of biomechanics 2010-03, Vol.43 (4), p.599-605
• Main Authors: Sztefek, Pavel, Vanleene, Maximilien, Olsson, Robin, Collinson, Rebecca, Pitsillides, Andrew A, Shefelbine, Sandra
• Format: Article
• Language: English
• Subjects: Adaptation, Physiological - physiology; Animals; Biological and medical sciences; Biomechanics. Biorheology; Bone remodelling; Bone strain; Bones; Computer Simulation; Digital image correlation; Elastic Modulus - physiology; Elasticity Imaging Techniques - methods; Finite element analysis; Fundamental and applied biological sciences. Psychology; Loading; Male; Mice; Mice, Inbred C57BL; Models, Biological; Mouse; Physical Medicine and Rehabilitation; Signal Processing, Computer-Assisted; Skeleton and joints; Statistics as Topic; Strain gauges; Stress, Mechanical; Studies; Tibia - anatomy & histology; Tibia - physiology; Tissues, organs and organisms biophysics; Vertebrates: osteoarticular system, musculoskeletal system
• ISSN: 0021-9290; 1873-2380
• DOI: 10.1016/j.jbiomech.2009.10.042

Abstract Previous models of cortical bone adaptation, in which loading is imposed on the bone, have estimated the strains in the tissue using strain gauges, analytical beam theory, or finite element analysis. We used digital image correlation (DIC), tracing a speckle pattern on the surface of the bone during loading, to determine surface strains in a murine tibia during compressive loading through the knee joint. We examined whether these surface strains in the mouse tibia are modified following two weeks of load-induced adaptation by comparison with contralateral controls. Results indicated non-uniform strain patterns with isolated areas of high strain (0.5%), particularly on the medial side. Strain measurements were reproducible (standard deviation of the error 0.03%), similar between specimens, and in agreement with strain gauge measurements (between 0.1 and 0.2% strain). After structural adaptation, strains were more uniform across the tibial surface, particularly on the medial side where peak strains were reduced from 0.5% to 0.3%. Because DIC determines local strains over the entire surface, it will provide a better understanding of how strain stimulus influences the bone response during adaptation.