Assessment of Maceration Techniques Used to Remove Soft Tissue from Bone in Cut Mark Analysis

Abstract

Maceration techniques employed in forensics must be effective without compromising the bone's integrity and morphology, and prevent destruction of evidence. Techniques must also be fast, safe, easily obtainable and inexpensive; not all techniques currently employed are appropriate for forensic use. To evaluate the most suitable approach, seven techniques including current and new methodologies were applied to fresh, fleshed porcine ribs exhibiting cut marks. A sample size of 30 specimens per technique was examined under scanning electron microscopy at the cut mark and the surrounding uncompromised regions; a scoring system of effectiveness was applied. The previously unpublished microwave method fared best for bone and cut mark preservation. Sodium hypochlorite destroyed cut marks, and was deemed unsuitable for forensic analysis. No single technique fulfilled all criteria; however, this study provides a benchmark for forensic anthropologists to select the most appropriate method for their situation, while maintaining the high standards required by forensic science.

Reflectance Transformation Imaging (RTI) for the Documentation of Saw Mark Characteristics

“…All specimens were macerated on the same day of purchase in the UCL Bioarchaeology Laboratory utilizing hot water enzyme maceration. The specimens were macerated prior to imparting trauma to enhance replicability and ensure that the cut surface characteristics remained undamaged for documentation and analysis (25).…”

Recommended Practices for Macerating Human Thyroid Cartilage

“…Methods to remove soft tissue from bone in forensic settings have been well-documented in the literature (5)(6)(7)(8)(9)(10)(11). Soft tissue removal methods each have their own drawbacks in terms of time, laboratory safety, and the risk of accidental damage to cartilage and bone (9).…”

Criminal Dismemberment

“…All of the methods carry some potential for damage to the bone, and one emerging theme suggests that any method used should be monitored closely throughout the investigation process, thereby allowing the practitioner greater control. In reality, there has been little research into the impact of techniques on cut marks on the bone (King and Birch, 2015), creating a situation in which there has been no quantification of the level of damage that might be experienced, especially to exposed AQ 10 K23112_C009.indd 125 12/24/16 5:53:50 PM cancellous bone. This in turn will have an impact on the presentation of conclusions in court.…”

“…Whilst it has not been investigated in relation to cut marks, even with this technique, consideration should still be paid to the potential for shrinkage and the effect that this might have on the analysis of cut marks, when bone is immersed in water and subsequently dried (Todd, 1923(Todd, , 1925Lindsten, 2002). The introduction of chemicals to speed up the process of biological breakdown, such as detergents, washing powders or sodium hydroxide (Fenton et al, 2003;Mairs et al, 2004;Uhre et al, 2015) or enzymes such as trypsin, pepsin or papain (Yin et al, 2010;Simonsen et al, 2011;Uhre et al, 2015) can speed up the maceration process; however, issues of damage to the surface of the bone have been identified and extreme care is advocated in their use (Shelton and Buckley, 1990;Mairs et al, 2004;Steadman et al, 2006;King and Birch, 2015). The chemical that has been widely used but has been shown to be most destructive is bleach (Mann and Berryman, 2012) leading to researchers such as Steadman et al (2006) warning against its use in any forensic situation.…”

“…The chemical that has been widely used but has been shown to be most destructive is bleach (Mann and Berryman, 2012) leading to researchers such as Steadman et al (2006) warning against its use in any forensic situation. Finally, King and Birch (2015) investigated the possibility of utilizing microwave maceration heat to remove soft tissue from the bone, finding that this delivers the ability to remove soft tissue speedily whilst causing minimum damage to the underlying bone. This is not a widely used method however, and further research is required to support these claims and ensure that parameters are established, which ensure that the bone is not overheated and damaged.…”