Limits...
Injury risk assessment of non-lethal projectile head impacts.

Oukara A, Nsiampa N, Robbe C, Papy A - Open Biomed Eng J (2014)

Bottom Line: Based on the principle that equal rigid wall maximal impact forces will produce equal damage on the head, these limits can be determined for any other projectile.This paper proposes a comparison between the "force wall approach" and two different head models.The first one is a numerical model (Strasbourg University Finite Element Head Model-SUFEHM) from Strasbourg University; the second one is a mechanical surrogate (Ballistics Load Sensing Headform-BLSH) from Biokinetics.

View Article: PubMed Central - PubMed

Affiliation: Royal Military Academy-Department of Weapon Systems and Ballistics-30 Avenue de la Renaissance, 1000 Brussels, Belgium ; Polytechnic Military School, 17 Bordj El-Bahri, Algiers, Algeria ; University of Liège (ULg)-Aerospace & Mechanical Engineering Department (LTAS) - 1, Chemin des Chevreuils, 4000 Liège, Belgium.

ABSTRACT
Kinetic energy non-lethal projectiles are used to impart sufficient effect onto a person in order to deter uncivil or hazardous behavior with a low probability of permanent injury. Since their first use, real cases indicate that the injuries inflicted by such projectiles may be irreversible and sometimes lead to death, especially for the head impacts. Given the high velocities and the low masses involved in such impacts, the assessment approaches proposed in automotive crash tests and sports may not be appropriate. Therefore, there is a need of a specific approach to assess the lethality of these projectiles. In this framework, some recent research data referred in this article as "force wall approach" suggest the use of three lesional thresholds (unconsciousness, meningeal damages and bone damages) that depend on the intracranial pressure. Three corresponding critical impact forces are determined for a reference projectile. Based on the principle that equal rigid wall maximal impact forces will produce equal damage on the head, these limits can be determined for any other projectile. In order to validate the consistence of this innovative method, it is necessary to compare the results with other existing assessment methods. This paper proposes a comparison between the "force wall approach" and two different head models. The first one is a numerical model (Strasbourg University Finite Element Head Model-SUFEHM) from Strasbourg University; the second one is a mechanical surrogate (Ballistics Load Sensing Headform-BLSH) from Biokinetics.

No MeSH data available.


Related in: MedlinePlus

ICP and head force relation curve [3].
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Figure 3: ICP and head force relation curve [3].

Mentions: The first step of the study was to define a physiological benchmark parameter for cranial impact damage. Based on head protection impacts on Human Biological Models (HBM) and Animal Biological Models (ABM), the Intracranial Pressure (ICP) has been correlated to head injuries. The role of the ICP in the head damage has already been demonstrated in previous studies, for other types of impacts [4]. The ICP is measured on cisterna magna, relatively near the cerebellum [3]. The head damage curve linking the maximum ICP to the impact velocity for the XM1006 was determined using the different impact data on the temporal, frontal and parietal head parts for the low velocities. Only the temporal impacts are considered for the high velocities according to the worst case scenario approach (Fig. 2) [3]. The clinical findings on HBM and ABM allowed defining the damage threshold values presented in Table 1 [5]. Then, through numerical simulations, the relation between ICP and maximum impact force was derived (Fig. 3). This relation is supposed to be the same for any projectile impact [3]. Equation (1) gives the relation between maximum impact force on the head and impact velocity. This relation is obtained by combining the data from Fig. (2) and Fig. (3).


Injury risk assessment of non-lethal projectile head impacts.

Oukara A, Nsiampa N, Robbe C, Papy A - Open Biomed Eng J (2014)

ICP and head force relation curve [3].
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4231376&req=5

Figure 3: ICP and head force relation curve [3].
Mentions: The first step of the study was to define a physiological benchmark parameter for cranial impact damage. Based on head protection impacts on Human Biological Models (HBM) and Animal Biological Models (ABM), the Intracranial Pressure (ICP) has been correlated to head injuries. The role of the ICP in the head damage has already been demonstrated in previous studies, for other types of impacts [4]. The ICP is measured on cisterna magna, relatively near the cerebellum [3]. The head damage curve linking the maximum ICP to the impact velocity for the XM1006 was determined using the different impact data on the temporal, frontal and parietal head parts for the low velocities. Only the temporal impacts are considered for the high velocities according to the worst case scenario approach (Fig. 2) [3]. The clinical findings on HBM and ABM allowed defining the damage threshold values presented in Table 1 [5]. Then, through numerical simulations, the relation between ICP and maximum impact force was derived (Fig. 3). This relation is supposed to be the same for any projectile impact [3]. Equation (1) gives the relation between maximum impact force on the head and impact velocity. This relation is obtained by combining the data from Fig. (2) and Fig. (3).

Bottom Line: Based on the principle that equal rigid wall maximal impact forces will produce equal damage on the head, these limits can be determined for any other projectile.This paper proposes a comparison between the "force wall approach" and two different head models.The first one is a numerical model (Strasbourg University Finite Element Head Model-SUFEHM) from Strasbourg University; the second one is a mechanical surrogate (Ballistics Load Sensing Headform-BLSH) from Biokinetics.

View Article: PubMed Central - PubMed

Affiliation: Royal Military Academy-Department of Weapon Systems and Ballistics-30 Avenue de la Renaissance, 1000 Brussels, Belgium ; Polytechnic Military School, 17 Bordj El-Bahri, Algiers, Algeria ; University of Liège (ULg)-Aerospace & Mechanical Engineering Department (LTAS) - 1, Chemin des Chevreuils, 4000 Liège, Belgium.

ABSTRACT
Kinetic energy non-lethal projectiles are used to impart sufficient effect onto a person in order to deter uncivil or hazardous behavior with a low probability of permanent injury. Since their first use, real cases indicate that the injuries inflicted by such projectiles may be irreversible and sometimes lead to death, especially for the head impacts. Given the high velocities and the low masses involved in such impacts, the assessment approaches proposed in automotive crash tests and sports may not be appropriate. Therefore, there is a need of a specific approach to assess the lethality of these projectiles. In this framework, some recent research data referred in this article as "force wall approach" suggest the use of three lesional thresholds (unconsciousness, meningeal damages and bone damages) that depend on the intracranial pressure. Three corresponding critical impact forces are determined for a reference projectile. Based on the principle that equal rigid wall maximal impact forces will produce equal damage on the head, these limits can be determined for any other projectile. In order to validate the consistence of this innovative method, it is necessary to compare the results with other existing assessment methods. This paper proposes a comparison between the "force wall approach" and two different head models. The first one is a numerical model (Strasbourg University Finite Element Head Model-SUFEHM) from Strasbourg University; the second one is a mechanical surrogate (Ballistics Load Sensing Headform-BLSH) from Biokinetics.

No MeSH data available.


Related in: MedlinePlus