Stress and deformation in a sutured tendon repair; an in-silico model

Many suture repairs have been described to re-approximate severed tendons, yet no one repair is regarded as the gold standard. At present, 25% of hand tendon repairs do not obtain satisfactory mobility following healing, and over 7% of repairs re-rupture (1). Concluding the ideal suture repair would benefit over 800,000 people in the UK who suffer tendon injury per annum (2). Finite element (FE) modelling enables detailed stress analysis of implantable devices and materials for tissue regeneration. However, the in silico model is limited by the description of biological tissues. Past 2D (3) and 3D (4) isotropic descriptions of tendon are unsuitable for modelling complex suture repair geometry. As such, the aim of this work was to mathematically describe tendon tissue, informed by ex vivo tensile testing, to model and compare stress patterns arising due to various suture techniques.