Stabbing energy and force required for pocket-knives to pierce ribs

Bolliger, Stephan A.<sup>1</sup>; Kneubuehl, Beat P.<sup>2</sup>; Thali, Michael J.<sup>1</sup>; Eggert, Sebastian<sup>1</sup>; Siegenthaler, Lea<sup>1</sup>

Affiliations

¹Department of Forensic Medicine and Imaging, Zurich Institute of Forensic Medicine, University of Zurich, Winterthurerstrasse 190/52, 8057 Zurich, Switzerland

²BPK Consulting, Thun, Switzerland

³Institute of Forensic Medicine, Centre for Forensic Physics and Ballistics, University of Bern, Bern, Switzerland

Abstract and keywords

In addition to reconstructing the course of events, the medical examiner will often have to answer questions regarding the force necessary to inflict a certain injury in stabbing incidents. Several groups have examined the force needed to penetrate soft-tissue and clothing; however, no studies addressing the energy needed for penetrating ribs exist. Therefore, we decided to investigate this force on an animal model.

Ribs from healthy, 8 to 10-month-old pigs were used as a substitute for human ribs. These ribs were then stabbed either transversely or longitudinally with two different pocket-knife blades, namely a Swiss Army pocket knife and a sturdier pocket knife (Classic Schnitzmesser, Herbertz Solingen) dropped from a drop-tower at defined heights and therefore defined energies.

Longitudinally orientated stabs showed complete piercing of the ribs at approximately 11 Joules (J) or with a stabbing force in excess of 906 Newton (N) for both blade types. Transversely orientated stabs, however, displayed complete piercing between 11 and 16 J, or in excess of 1198 N, with the sturdy pocket knife tending to require a little more energy than the Swiss army pocket knife.

Young adult porcine ribs are completely pierced by pocket knife blades at energies between 11 and 16 J. Assuming the porcine ribs are comparable to those ribs of young adult humans, our results indicate that a complete penetration of the chest wall through the ribs by stabbing with a pocket knife is rather easily achieved.

Keywords: Stab energy; Stab force; Pocket-knife; Rib piercing; Forensic

Links

DOI: 10.1007/s12024-016-9803-z

PubMed: 27503509

WoS: 000390036400002

History

Accepted: 2016-07-21

Online: 2006-08-09

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Cited By (7)

Year	Entry
2020	Gaudet JR, Lievers WB, Fairgrieve SI. Development and commissioning of an instrumented pneumatic device to simulate blunt- and sharp-force trauma. Forensic Sci Int. February 2020;307:110123.
2020	Hogue M, Fairgrieve SI, Lievers WB. Stabbing angle alters peak force and work during sharp force trauma of porcine ribs. Forensic Sci Int. September 2020;314:110373.
2021	Waltenberger L, Beitel S, Benecker B, Heimel P, Weninger W, Kanz F. A histological comparison of non-human rib models suited for sharp force trauma analysis. Forensic Sci Int. February 2021;319:110661.
2018	Nolan G, Hainsworth SV, Rutty GN. Forces generated in stabbing attacks: an evaluation of the utility of the mild, moderate and severe scale. Int J Legal Med. January 2018;132(1):229-236.
2020	Bolliger SA, Wallace E, Dobay A, Knaute DF, Thali MJ, Barrera V. The cutting edge: an investigation into the pressure necessary for cutting skin with different knife blade types. Int J Legal Med. May 2020;134(3):1133-1140.
2023	Heckmann V, Engum V, Simon G, Poór VS, Tóth D, Molnar TF. Piercing the surface: a mechanical analysis of stabbing with household tools. J Forensic Sci. July 2023;68(4):1218-1227.
2022	Hogue M. Effects of Blade Angle on the Force and Work During Sharp Force Trauma of Porcine Ribs [Master's thesis]. Sudbury, ON: Laurentian University; 2022.