Biomechanical Gain in Joint Excursion from the Curvature of the Achilles Tendon: Role of the Geometrical Arrangement of Inflection Point, Center of Rotation, and Calcaneus

Ryuta Kinugasa; Naoto Yamamura; Shu Takagi; Shantanu Sinha

doi:10.3390/diagnostics11112097

Biomechanical Gain in Joint Excursion from the Curvature of the Achilles Tendon: Role of the Geometrical Arrangement of Inflection Point, Center of Rotation, and Calcaneus

Diagnostics (Basel). 2021 Nov 12;11(11):2097. doi: 10.3390/diagnostics11112097.

Authors

Ryuta Kinugasa¹, Naoto Yamamura², Shu Takagi², Shantanu Sinha³

Affiliations

¹ Department of Human Sciences, Kanagawa University, Yokohama 221-8686, Japan.
² Department of Mechanical Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan.
³ Muscle Imaging and Modeling Laboratory, Department of Radiology, University of California San Diego, San Diego, CA 92121, USA.

Abstract

The dorsal movement of the Achilles tendon during ankle rotation is restricted by anatomical obstructions. Previously, we demonstrated that the anatomical obstruction provides a gain (gain_AT) in the proximal displacement of the calcaneus compared to the change in the Achilles tendon length. Here, we empirically validate and extend our previous modeling study by investigating the effects of a broad range of obstruction locations on gain_AT. The largest gain_AT could be achieved when the obstruction was located on the most ventral and distal sides within the physiological range of the Achilles tendon, irrespective of the ankle position.

Keywords: ankle geometrical model; ankle plantarflexion; calcaneus position; gear; joint kinematics.

Abstract

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