A Rare Case of an Intact Bone Plug Associated with a Gunshot Exit Wound

Abstract

This case study presents an unusual manifestation of gunshot trauma in skeletal tissue from a post-World War II human rights abuse sample uncovered in Vilnius, Lithuania. After briefly reviewing the typical wound appearance of projectile trauma in the cranium, we discuss the presence of an intact bone plug associated with a gunshot exit wound in an individual from the Tuskulenai Case. While this individual demonstrated typical gunshot entry and exit wounds to the cranium consistent with high-velocity trauma, the bone plug indicates that the projectile likely lost much of its kinetic energy while traveling through the cranium resulting in a low-velocity impact at the exit site. This study reviews a similar instance of a bone plug recovered from a bioarcheological sample in Peru and emphasizes the importance of thorough archeological excavations of mass graves.

A novel hypothesis for the formation of conoidal projectile wounds in sandwich bones

“…Despite lack of production of intact bioceramic conoids, comparison of plug morphology produced by low velocity impacts [15][16][17] with residual fracture morphology subsequent to medium and high velocity impacts reveals similarities that are indicative of a common fracture process. Whilst overlap in external morphology between conoidal wounds produced by blunt and projectile trauma has been reported previously [50][51][52], this is the first report of wounds inflicted at 150 m/s being identical internally to those produced at 850 m/s.…”

“…The first description of such plugs was provided by Murphy et al [15] who described frontal and parietal plugs associated with perforating wounds of unknown aetiology in archaeological material. Murphy et al [16] later described two more entry wound plugs in a parietal (produced by impact with a train) and occipital (produced by a cross-bow bolt), and Bird and Fleischman [17] later provided additional information on a frontal bone exit wound plug produced by low velocity bullet impact. Significantly, these tri-layered bone plugs are conoidal and the hole they fit into in their parent bone is bevelled accordingly; internally for an entry [15,16], and externally for an exit [17].…”

“…Murphy et al [16] later described two more entry wound plugs in a parietal (produced by impact with a train) and occipital (produced by a cross-bow bolt), and Bird and Fleischman [17] later provided additional information on a frontal bone exit wound plug produced by low velocity bullet impact. Significantly, these tri-layered bone plugs are conoidal and the hole they fit into in their parent bone is bevelled accordingly; internally for an entry [15,16], and externally for an exit [17]. The compressive side of the plug in the outer cortical layer may exhibit compressive damage, whilst the tensile side of the plug in the inner cortical layer is often characterised by radial fractures emanating from a central point, a process resulting in a distinct stellate fracture pattern.…”

A scanning electron microscopy study of projectile entry fractures in cortical bone; genesis and microarchitectural features

“…Theoretically, compression due to plastic deformation and/or fracture would cause immediate contact with a wider projectile radius and thus result in only one ring crack. In support of this hypothesis, four of the five conoids described from the archaeological and forensic literature displayed a compressed cortical roof [38][39][40], as did the two most intact conoids in our previous experimental series [4]. This hypothesis cannot fully explain lack of multiple ring cracks, however, as the rebound impacts exhibited both plastic deformation and more than one generation of ring crack.…”

“…In contrast, SEM analysis of the intact cortical roof of the conoid produced at 74 m/s did not show any ring cracks (see [ 4 ] for µCT cross-sectional analysis of this conoid). Ring cracks large enough to detect with µCT were also absent from a second conoid resulting from a 57 m/s impact in the same experimental series [ 4 ] and are not present in the images of intact conoids reported in the literature [ 38 – 40 ]. Variation in ring crack number and distribution around the impact site has also been demonstrated in other ceramic materials including dense alumina [ 35 ] and coarse alumina subjected to repeated load cycles [ 37 ].…”