TY - JOUR
T1 - Enthesis strength, toughness and stiffness
T2 - an image-based model comparing tendon insertions with varying bony attachment geometries
AU - Golman, Mikhail
AU - Birman, Victor
AU - Thomopoulos, Stavros
AU - Genin, Guy M.
N1 - Publisher Copyright:
© 2021 The Author(s).
PY - 2021
Y1 - 2021
N2 - Tendons of the body differ dramatically in their function, mechanics and range of motion, but all connect to bone via an enthesis. Effective force transfer at the enthesis enables joint stability and mobility, with strength and stiffness arising from a fibrous architecture. However, how enthesis toughness arises across tendons with diverse loading orientations remains unclear. To study this, we performed simultaneous imaging of the bone and tendon in entheses that represent the range of tendon-to-bone insertions and extended a mathematical model to account for variations in insertion and bone geometry. We tested the hypothesis that toughness, across a range of tendon entheses, could be explained by differences observed in interactions between fibre architecture and bone architecture. In the model, toughness arose from fibre reorientation, recruitment and rupture, mediated by interactions between fibres at the enthesis and the bony ridge abutting it. When applied to tendons sometimes characterized as either energy-storing or positional, the model predicted that entheses of the former prioritize toughness over strength, while those of the latter prioritize consistent stiffness across loading directions. Results provide insight into techniques for surgical repair of tendon-to-bone attachments, and more broadly into mechanisms for the attachment of highly dissimilar materials.
AB - Tendons of the body differ dramatically in their function, mechanics and range of motion, but all connect to bone via an enthesis. Effective force transfer at the enthesis enables joint stability and mobility, with strength and stiffness arising from a fibrous architecture. However, how enthesis toughness arises across tendons with diverse loading orientations remains unclear. To study this, we performed simultaneous imaging of the bone and tendon in entheses that represent the range of tendon-to-bone insertions and extended a mathematical model to account for variations in insertion and bone geometry. We tested the hypothesis that toughness, across a range of tendon entheses, could be explained by differences observed in interactions between fibre architecture and bone architecture. In the model, toughness arose from fibre reorientation, recruitment and rupture, mediated by interactions between fibres at the enthesis and the bony ridge abutting it. When applied to tendons sometimes characterized as either energy-storing or positional, the model predicted that entheses of the former prioritize toughness over strength, while those of the latter prioritize consistent stiffness across loading directions. Results provide insight into techniques for surgical repair of tendon-to-bone attachments, and more broadly into mechanisms for the attachment of highly dissimilar materials.
KW - energy-storing tendons
KW - fibrous tissues
KW - positional tendons
KW - tendon enthesis
KW - tendon-to-bone insertion
KW - toughness
UR - http://www.scopus.com/inward/record.url?scp=85122907626&partnerID=8YFLogxK
U2 - 10.1098/rsif.2021.0421
DO - 10.1098/rsif.2021.0421
M3 - Article
C2 - 34932930
AN - SCOPUS:85122907626
SN - 1742-5689
VL - 18
JO - Journal of the Royal Society Interface
JF - Journal of the Royal Society Interface
IS - 185
M1 - 20210421
ER -