Automatic rib unfolding in postmortem computed tomography: diagnostic evaluation of the OpenRib software compared with the autopsy in the detection of rib fractures

  • Martin KoloppEmail author
  • Nicolas Douis
  • Ayla Urbaneja
  • Cédric Baumann
  • Pedro Augusto Gondim Teixeira
  • Alain Blum
  • Laurent Martrille
Original Article



The main objective of this study was to evaluate the diagnostic performance of the OpenRib software against the gold standard of autopsy in the detection of rib fractures. The secondary objective was to measure inter-rater agreement between each radiological reader.

Materials and methods

Thirty-six subjects who underwent postmortem CT and autopsy were included in this study. Rib fractures were first assessed during the autopsy by carefully dissecting and examining each rib. They were also independently evaluated by three readers using OpenRib software. This software produces from postmortem CT images a reformat of the rib cage and a display of all ribs in a single plane. Each reader was asked to determine if the rib was fractured and, if so, whether the fracture was single or multiple.


After exclusions, 649 ribs were included in the statistical analysis. The two readers with a similar level of experience showed a satisfactory inter-rater agreement and a sensitivity of 0.73 and 0.83 with a specificity of 0.95 and 0.91. However, the experienced reader diagnosed significantly more fractures than the autopsy and the other two readers (p < 0.001).


The use of automatic rib unfolding software in postmortem CT allows an efficient and accurate assessment of rib fractures and enables the diagnosis of fractures that cannot be detected during a standard autopsy. For now, this method seems to be the simplest that can be routinely performed; however, it requires training time in order to be sufficiently effective.


Rib fractures Postmortem computed tomography Image processing Diagnostic performance 


Compliance with ethical standards

Subjects of this study are deceased; the assessment of rib fractures is routinely performed at an autopsy and radiological post-processing was performed using standard PMCT images. Therefore, the approval of the ethics committee was not necessary.

Conflict of interest

One of the authors involved in this work participates in a non-remunerated research contract with Canon Medical systems, the developer of the software used for rib cage unfolding. The rest of the authors declare that they have no conflict of interest and state that this work has not received any funding.


  1. 1.
    Kaewlai R, Avery LL, Asrani AV, Novelline RA (2008) Multidetector CT of blunt thoracic trauma. RadioGraphics 28:1555–1570. CrossRefPubMedGoogle Scholar
  2. 2.
    Gondim Teixeira PA, Blum A (2017) Clinical application of musculoskeletal CT: trauma, oncology, and postsurgery. In: Medical radiology. Springer, Berlin, pp 1–27. CrossRefGoogle Scholar
  3. 3.
    Homann G, Mustafa DF, Ditt H, Spengler W, Kopp HG, Nikolaou K, Horger M (2015) Improved detection of bone metastases from lung cancer in the thoracic cage using 5- and 1-mm axial images versus a new CT software generating rib unfolding images: comparison with standard 18F-FDG-PET/CT. Acad Radiol 22:505–512. CrossRefPubMedGoogle Scholar
  4. 4.
    Ha JY, Jeon KN, Bae K, Choi BH (2017) Effect of bone reading CT software on radiologist performance in detecting bone metastases from breast cancer. Br J Radiol 90:20160809. CrossRefPubMedPubMedCentralGoogle Scholar
  5. 5.
    Seuss H, Dankerl P, Cavallaro A, Uder M, Hammon M (2016) Osteoblastic lesion screening with an advanced post-processing package enabling in-plane rib reading in CT-images. BMC Med Imaging 16:39. CrossRefPubMedPubMedCentralGoogle Scholar
  6. 6.
    Bier G, Mustafa DF, Kloth C, Weisel K, Ditt H, Nikolaou K, Horger M (2016) Improved follow-up and response monitoring of thoracic cage involvement in multiple myeloma using a novel CT postprocessing software: the lessons we learned. Am J Roentgenol 206:57–63. CrossRefGoogle Scholar
  7. 7.
    Horger M, Ditt H, Liao S, Weisel K, Fritz J, Thaiss WM, Kaufmann S, Nikolaou K, Kloth C (2017) Automated “Bone Subtraction” image analysis software package for improved and faster CT monitoring of longitudinal spine involvement in patients with multiple myeloma. Acad Radiol 24:623–632. CrossRefPubMedGoogle Scholar
  8. 8.
    Bier G, Schabel C, Othman A, Bongers MN, Schmehl J, Ditt H, Nikolaou K, Bamberg F, Notohamiprodjo M (2015) Enhanced reading time efficiency by use of automatically unfolded CT rib reformations in acute trauma. Eur J Radiol 84:2173–2180. CrossRefPubMedGoogle Scholar
  9. 9.
    Ringl H, Lazar M, Töpker M, Woitek R, Prosch H, Asenbaum U, Balassy C, Toth D, Weber M, Hajdu S, Soza G, Wimmer A, Mang T (2015) The ribs unfolded - a CT visualization algorithm for fast detection of rib fractures: effect on sensitivity and specificity in trauma patients. Eur Radiol 25:1865–1874. CrossRefPubMedGoogle Scholar
  10. 10.
    Dankerl P, Seuss H, Ellmann S, Cavallaro A, Uder M, Hammon M (2017) Evaluation of rib fractures on a single-in-plane image reformation of the rib cage in CT examinations. Acad Radiol 24:153–159. CrossRefPubMedGoogle Scholar
  11. 11.
    Khung S, Masset P, Duhamel A, Faivre JB, Flohr T, Remy J, Remy-Jardin M (2017) Automated 3D rendering of ribs in 110 polytrauma patients: strengths and limitations. Acad Radiol 24:146–152. CrossRefPubMedGoogle Scholar
  12. 12.
    Glemser PA, Pfleiderer M, Heger A, Tremper J, Krauskopf A, Schlemmer HP, Yen K, Simons D (2017) New bone post-processing tools in forensic imaging: a multi-reader feasibility study to evaluate detection time and diagnostic accuracy in rib fracture assessment. Int J Legal Med 131:489–496. CrossRefPubMedGoogle Scholar
  13. 13.
    Blum A, Kolopp M, Teixeira PG, Stroud T, Noirtin P, Coudane H, Martrille L (2018) Synergistic role of newer techniques for forensic and postmortem CT examinations. AJR Am J Roentgenol 211:1–8. CrossRefGoogle Scholar
  14. 14.
    Tobon-Gomez C, Stroud T, Cameron J, Elcock D, Murray A, Wyeth D, Conway C, Reynolds S, Teixeira PA, Blum A, Plakas C (2017) OpenRib clinical application. In: Computational methods and clinical applications in musculoskeletal imaging. Paper presented at MICCAI, Quebec City, 10 September (pp 35-45). Quebec City, CanadaGoogle Scholar
  15. 15.
    Tobon-Gomez C, Stroud T, Cameron J, Elcock D, Murray A, Wyeth D, Conway C, Reynolds S, Teixeira PA, Blum A, Plakas C (2018) Unfolded cylindrical projection for rib fracture diagnosis. In: Glocker B., Yao J., Vrtovec T., Frangi A., Zheng G. (eds) Computational methods and clinical applications in musculoskeletal imaging. MSKI 2017. Lecture Notes in Computer Science, vol 10734. Springer, Cham. pp. 36–47. CrossRefGoogle Scholar
  16. 16.
    Urbaneja A, De Verbizier J, Formery AS, Tobon-Gomez C, Nace L, Blum A, Gondim Teixeira PA (2019) Automatic rib cage unfolding with CT cylindrical projection reformat in polytraumatized patients for rib fracture detection and characterization: feasibility and clinical application. Eur J Radiol 110:121–127. CrossRefPubMedGoogle Scholar
  17. 17.
    Love JC, Symes SA (2004) Understanding rib fracture patterns: incomplete and buckle fractures. J Forensic Sci 49:1153–1158CrossRefGoogle Scholar
  18. 18.
    Daegling DJ, Warren MW, Hotzman JL, Self CJ (2008) Structural analysis of human rib fracture and implications for forensic interpretation. J Forensic Sci 53:1301–1307. CrossRefPubMedGoogle Scholar
  19. 19.
    Scheirs S, Langenhorst W, Malgosa A, Ortega-Sánchez M, McGlynn H, Santos C, Jordana X, Rodriguez-Baeza A, Galtés I (2018) Perimortem fracture pattern in ribs by blunt force trauma. Int J Legal Med 132:1205–1213. CrossRefPubMedGoogle Scholar
  20. 20.
    Yang K, Lynch M, O’Donnell C (2011) “Buckle” rib fracture: an artifact following cardio-pulmonary resuscitation detected on postmortem CT. Legal Med 13:233–239. CrossRefPubMedGoogle Scholar
  21. 21.
    Schulze C, Hoppe H, Schweitzer W, Schwendener N, Grabherr S, Jackowski C (2013) Rib fractures at postmortem computed tomography (PMCT) validated against the autopsy. Forensic Sci Int 233:90–98. CrossRefPubMedGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Service de médecine légaleCHRU de NancyVandœuvre-lès-NancyFrance
  2. 2.Service d’imagerie GuillozCHRU de NancyNancyFrance
  3. 3.Plateforme d’Aide à la Recherche Clinique (PARC)UMDS, CHRU de NancyVandœuvre-lès-NancyFrance

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