Estimating the Timing of Long Bone Fractures: Correlation Between the Postmortem Interval, Bone Moisture Content, and Blunt Force Trauma Fracture Characteristics*

Abstract

There is very limited knowledge about how long perimortem fracture characteristics persist into the postmortem interval (PMI). Therefore, in this study, 60 porcine long bones were exposed to natural taphonomic conditions and fractured with a steel bone breaking apparatus every 28 days throughout a 141-day period. Differences between macroscopic blunt force trauma fracture characteristics (fracture angle, surface morphology, and outline) were examined to determine if they varied over time or in relationship to bone moisture content (ash weight) and overall assessment. There are significant relationships between (1) PMI and percent ash weight (%AW), fracture surface, and fracture angle and (2) %AW and fracture surface and fracture angle. Bone moisture content correlates significantly with fracture morphology and other characteristics commonly used by forensic anthropologists to determine the timing of traumatic injuries. However, fracture characteristics normally associated with perimortem trauma can persist long into the PMI.

New insights in the analysis of blunt force trauma in human bones. Preliminary results

“…In literature, there are already many characteristics known to make the distinction between perimortem and postmortem fractures like colour, smooth and rough edges [8,16,17]. In reality, however, this distinction is still a challenge in forensic cases, especially when the bones are still fresh.…”

Fatal cranial injury in an individual from Messina (Sicily) during the times of the Roman Empire

“…51e53 Cranial computed tomography scanning (Fig. 9) clearly demonstrate the presence of splinter bone attached to the fracture margins confirming that the lesion was made on 'fresh' bone, 21 and excludes the possibility that the lesion was caused a long time after death on dry bone by taphonomic factors. The characteristics and position of the lesion on the right parietal, the absence of a bony reaction on the margins of the perforation, and the presence of internal bevelling, all seem to indicate a perimortem trauma, occurring immediately before death (possibly the cause of death) or immediately after death.…”

“…35,54 However, the bones retain 'fresh' properties for a considerable time after death. 21,55,56 Therefore caution should be exercised when determining the timing of fractures. There are some analytical methods for studying the timing of a bone fracture of the postcranial skeleton, 57,58 but no reference is available for the skull.…”

“…39e41 Perimortem injuries are those that occur at or near the time of death and are distinguished by an absence of any evidence of healing; the uniform presence of stain from water, soil, or vegetation on broken and adjacent bone surfaces; the presence of greenstick fractures, incomplete fractures, spiral fractures, and depressed and compressed fractures. 21,30 Perimortem usually implies that the injury is directly associated with the cause of death. 20 Postmortem injuries are those that have occurred after death and tend to be characterized by smaller fragments, nonuniform coloration of the fracture ends and the adjacent bone surface, especially light-colored edges.…”

Sepultamentos secundários com manipulações intencionais no Brasil: um estudo de caso no sítio arqueológico Pedra do Cachorro, Buíque, Pernambuco, Brasil

“…Quanto à antiguidade da fratura, o principal interesse está em distinguir aquelas que são perimortem, ou produzidas em ossos frescos, ou seja, contendo substância orgânica (colágeno), daquelas que foram produzidas postmortem em ossos secos e sem conteúdo orgânico (Turner II;Turner, 1990;Sauer, 1998;Villa;Mahieu, 1991;Ubelaker;Adams, 1995;Wieberg;Wescott, 2008). Apesar de que, em alguns casos, essa distinção possa ser problemática -em particular, em ossos planos e com pouca espessura cortical, como do quadril, costelas e escápulas -, geralmente não resulta difícil para o olhar de de animais, para inferir a origem de atividades de caça e processamento em nossos ancestrais hominídeos do continente africano (Binford, 1981;Kroll, 1986;Bunn et al, 1980;Lupo;O'Connel, 2002;Potts;Shipman, 1981;Selvaggio, 1994;Rose, 1983).…”