Stephan A Bolliger1, Beat P Kneubuehl2, Michael J Thali3, Sebastian Eggert3, Lea Siegenthaler4. 1. Department of Forensic Medicine and Imaging, Zurich Institute of Forensic Medicine, University of Zurich, Winterthurerstrasse 190/52, 8057, Zurich, Switzerland. stephan.bolliger@irm.uzh.ch. 2. BPK Consulting, Thun, Switzerland. 3. Department of Forensic Medicine and Imaging, Zurich Institute of Forensic Medicine, University of Zurich, Winterthurerstrasse 190/52, 8057, Zurich, Switzerland. 4. Institute of Forensic Medicine, Centre for Forensic Physics and Ballistics, University of Bern, Bern, Switzerland.
Abstract
PURPOSE: 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. METHOD: 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. RESULTS: 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. CONCLUSIONS: 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.
PURPOSE: 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. METHOD: 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. RESULTS: 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. CONCLUSIONS: 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.
Entities:
Keywords:
Forensic; Pocket-knife; Rib piercing; Stab energy; Stab force
Authors: Stephan A Bolliger; Steffen Ross; Lars Oesterhelweg; Michael J Thali; Beat P Kneubuehl Journal: J Forensic Leg Med Date: 2008-11-07 Impact factor: 1.614
Authors: L Oesterhelweg; S Ross; D Spendlove; C A Schoen; A Christe; M J Thali; S A Bolliger Journal: Leg Med (Tokyo) Date: 2007-06-12 Impact factor: 1.376
Authors: Sarah Schaerli; Richard Schulz; Dominic Gascho; Markus Enders; Sandra Baumann; Michael J Thali; Stephan A Bolliger Journal: Forensic Sci Med Pathol Date: 2017-12-02 Impact factor: 2.007