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arXiv · 1905.00801

Topology, geometry and mechanics of surgical Z-plasty

Elisabetta Matsumoto·Haiyi Liang·L Mahadevan
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Abstract

Reconstructive surgeries often use topological manipulation of tissue to minimize post-operative scarring. The most common version of this, Z-plasty, involves modifying a straight line cut into a Z-shape, followed by a rotational transposition of the resulting triangular pedicle flaps, and a final restitching the wound. This locally reorients the anisotropic stress field and reduces the potential for scarring. We analyze the planar geometry and mechanics of the Z-plasty to quantify the rotation of the overall stress field and the local forces on the restitched cut using theory, simulations and simple physical Z-plasty experiments with foam sheets that corroborate each other. Our study rationalizes the most typical surgical choice of this angle, and opens the way for a range of surgical decisions by characterizing the stresses along the cut.

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Elisabetta Matsumoto, Haiyi Liang, L Mahadevan. 2019-05-02. Topology, geometry and mechanics of surgical Z-plasty. https://doi.org/10.1103/physrevlett.120.068101

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