ORIGINAL ARTICLE An evaluation of the objectivity and reproducibility of shear wave elastography in estimating the post-mortem interval: a tissue biomechanical perspective Fabio De-Giorgio 1,2 & Gabriele Ciasca 1,3 & Ronel D’Amico 4 & Pietro Trombatore 4 & Anna D’Angelo 4 & Pierluigi Rinaldi 4 & Filippo Milano 5 & Emanuela Locci 6 & Marco De Spirito 3 & Ernesto d’Aloja 6 & Cesare Colosimo 4 & Vincenzo L. Pascali 1,2 Received: 13 June 2019 /Accepted: 8 July 2020 # Springer-Verlag GmbH Germany, part of Springer Nature 2020 Abstract Cadaveric rigidity—also referred to as rigor mortis—is a valuable source of information for estimating the time of death, which is a fundamental and challenging task in forensic sciences. Despite its relevance, assessing the level of cadaveric rigidity still relies on qualitative and often subjective observations, and the development of a more quantitative approach is highly demanded. In this context, ultrasound shear wave elastography (US SWE) appears to be a particularly well-suited technique for grading cadaveric rigidity, as it allows non-invasive quantification of muscle stiffness in terms of Young’s modulus (E), which is a widely used parameter in tissue biomechanics. In this pilot study, we measured, for the first time in the literature, changes in the mechanical response of muscular tissues from 0 to 60 h post-mortem (hpm) using SWE, with the aim of investigating its applicability to forensic practice. For this purpose, 26 corpses were included in the study, and the muscle mechanical response was measured at random times in the 0–60 hpm range. Despite the preliminary nature of this study, our data indicate a promising role of SWE in the quantitative determination of cadaveric rigidity, which is still currently based on qualitative and semiquantitative methods. A more in-depth study is required to confirm SWE applicability in this field in order to overcome some of the inherent limitations of the present work, such as the rather low number of cases and the non-systematic approach of the measurements. Keywords Time since death . Post-mortem interval . Rigor mortis . Shear wave elastography . Forensic science . Biomechanics . Ultrasound Abbreviations PMI Post-mortem interval SWE Shear wave elastography hpm Hours post-mortem Introduction Determining the time since death or the post-mortem interval (PMI) is a fundamental forensic science task [1, 2]. Although several qualitative and quantitative approaches have been Fabio De-Giorgio and Gabriele Ciasca contributed equally to this work. Electronic supplementary material The online version of this article (https://doi.org/10.1007/s00414-020-02370-5) contains supplementary material, which is available to authorized users. * Fabio De-Giorgio fabio.degiorgio@unicatt.it 1 Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy 2 Department of Health Care Surveillance and Bioetics, Section of Legal Medicine, Università Cattolica del Sacro Cuore, Rome, Italy 3 Dipartimento di Neuroscienze, Sezione di Fisica, Università Cattolica del Sacro Cuore, Rome, Italy 4 Unit of Radiology, Mater Olbia Hospital, SS, Olbia, Italy 5 Department of Biomedicine and Prevention, University of Rome “Tor Vergata”, Rome, Italy 6 Department of Medical Sciences and Public Health, Section of Legal Medicine, University of Cagliari, Cagliari, Italy https://doi.org/10.1007/s00414-020-02370-5 / Published online: 17 July 2020 International Journal of Legal Medicine (2020) 134:1939–1948