Al Makhzoomi Anas K, Kirk Thomas B, Allison Garry T
School of Allied Health, Faculty of Health Science, Curtin University, Perth, Western Australia, Australia.
School of Science, Engineering and Technology, RMIT University Vietnam, Ho Chi Minh City, Vietnam.
J Biomech. 2021 Nov 9;128:110790. doi: 10.1016/j.jbiomech.2021.110790. Epub 2021 Oct 6.
The response of white New Zealand rabbit Achilles tendons to load was assessed using mechanical measures and confocal arthroscopy (CA). The progression of fatigue-loading-induced damage of the macro- (tenocyte morphology, fiber anisotropy and waviness), as well as the mechanical profile, were assessed within the same non-viable intact tendon in response to prolonged cyclic and static loading (up to four hours) at different strain levels (3%, 6% and 9%). Strain-mediated repeated loading induced a significant decline in mechanical function (p < 0.05) with increased strain and cycles. Mechanical and structural resilience was lost with repeated loading (p < 0.05) at macroscales. The lengthening of D-periodicity correlated strongly with the overall tendon mechanical changes and loss of spindle shape in tenocytes. This is the first study to provide a clear concurrent assessment of form (morphology) and function (mechanics) of tendons undergoing different strain-mediated repeated loading at multiple-scale assessments. This study identifies a variety of multiscale properties that may contribute to the understanding of mechanisms of tendon pathology.
