Investigation of the force associated with the formation of lacerations and skull fractures

Abstract

Publication informationInternational Journal of Legal Medicine, 126 (6) ABSTRACTPost mortem examination is often relied upon in order to determine whether a suspicious death was natural, accidental, suicidal or homicidal. However, in many cases the mechanism by which a single injury has been inflicted cannot be determined with certainty based on pathological examination alone. Furthermore the current method of assessing applied force relating to injury is restricted to an arbitrary and subjective scale (mild, moderate, considerable, or severe). This study investigates the pathophysiological nature of head injuries caused by blunt force trauma, specifically in relation to the incidence and formation of a laceration. An experimental model was devised to assess the force required to cause damage to the scalp and underlying skull of porcine specimens following a single frontoparietal impact. This was achieved using a drop tower equipped with adapted instrumentation for data acquisition. The applied force and implement used could be correlated with resultant injuries and as such aid pathological investigation in the differentiation between falls and blows. Experimentation revealed prevalent patterns of injury specific to the reconstructed mechanism involved. It was found that the minimum force for the occurrence of a laceration was 4000 N.3

How hard is hard enough? An investigation of the force associated with lateral blunt force trauma to the porcine cranium

“…Similarly, a study conducted in England demonstrated that 26% of non-firearm related homicides involved blunt force trauma, 88% of which involved multiple blows to the head [2]. Another review of blunt force trauma cases over a period of 10 years (2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009) in Ireland demonstrated that 70% of blows resulted in both fracture of the skull and laceration of the scalp [3]. In Cape Town, South Africa homicide/assault is the second leading cause of premature death [4,5] and blunt force trauma forms a portion of these deaths [6].…”

“…Typically, these take the form of case studies which merely describe the wound morphology due to specific weapons [26][27][28][29][30][31]. Only a limited number of studies have attempted to analyse the associated force behind an impact due to a specific blunt instrument [3,23,32,33].…”

“…Those studies which have investigated lateral impact biomechanics have utilised a variety of different methodologies including: static compression tests [11] (as cited in [7]), drop tests [3,[12][13][14][15][16][17], free fall tests [18][19][20], impacts with a pneumatic/ hydraulic piston [21,22], gas gun tests [23,24] and pendulum set ups [25]. Specimens utilised in these tests have also varied greatly, comprising of intact human cadavers, intact cadaver heads, dry human skulls and porcine specimens.…”

Animal experimentation in forensic sciences: How far have we come?

“…On the other hand, applying alternative methods rather than using animals has provided, in the forensic field, important and reproducible results, as presented in Table 3 [74,[77][78][79][80][81][82][83][84][85][86][87][88]. And for many less elaborate projects, animals who have died from other causes can be used.…”

A subacute epidural haematoma extending over the occipital region and posterior cranial fossa due to a laceration in the transverse sinus

“…Additionally, there was no finding indicating poor nutrition when the autopsy was performed. Thus, it is likely that the head injury was accidental rather than inflicted and that he had fallen down stairs, bruising the occipital area against the flat surface because there was some suture diastases without laceration [15].…”