Decapitation: A Case Study and Review of the Literature

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Intentional and accidental separation of the head is well documented in the forensic
anthropological and bioarchaeological literature. Generally, decapitation refers to the act
of cutting, tearing, pulling, or otherwise removing the head from the trunk during the
perimortem interval. The process of decapitation can result from (1) suicide, (2)
homicide, (3) a traumatic accident, (4) a judicial execution, or (5) trophy taking.
Decapitation has been utilized as a method of killing or mutilating victims throughout
many periods of human history and has been documented during the Neolithic (e.g.
Kuijt, 2001), Bronze Age (e.g. Khudaverdyan, 2014), Iron Age (e.g. Armit, 2012),
Middle Ages (e.g. Carty, 2015), in prehistoric Peru (Cordy-Collins, 2001), and
California (e.g. Schwitalla et al., 2014). In a medicolegal context, it is not uncommon for
a forensic anthropologist to encounter remains where the head has been removed. In
interpreting and documenting this trauma, it is helpful to have a working knowledge of
common locations of decapitation and the soft tissue involved. To this end, the authors
present a literature review to 1) learn the most common anatomical location of
decapitation, 2) understand the process of decapitation to include common skeletal
locations and the anatomical structures involved, and 3) understand sharp-force and/or
blunt-force trauma to the neck. Finally, a case study is presented to highlight the findings
of the study.
A review of the literature identified 211 cases of complete decapitation in a medicolegal
context (both accidental and intentional). The age range of individuals in this case study
was 32 weeks in utero to 85 years (mean 38.66 years), with 65 females and 121 males
reported (Table 1; Figure 1). There were 12 cases where sex was not reported. Of these
cases, 98 clearly stated the anatomical location of the decapitation; only these cases are
discussed here (Figure 2). The majority of cases (n=69, 67%) occurred at the mid-neck,
in the region of the second to fifth cervical vertebrae. The other cases of decapitation
occurred either superior or inferior to these vertebrae, to include separation at the skull,
atlas, or axis (n=23, 24%) or below the sixth cervical vertebra (n=6, 6%). Of those
inferior to the sixth cervical vertebra, three cases (3%) of decapitation between the sixth
and seventh cervical and three cases (3%) between the seventh and first thoracic
vertebrae were found (Tsokos et al., 2004; Turillazzi et al., 2007). Of these 98 cases,
most common cause of death was ruled suicide (n=42, 40%); followed by
homicide/dismemberment (n=27, 29%); accidental (n=26, 28%); and three cases did not
list cause of death (n=3, 3%). Similar results for decapitation location were found within
the bioarchaeological literature; the mid-neck was most often the area of separation, with
the upper and lower regions being affected to alesser degree.
Remains recovered from two different proveniences were brought to the Washoe
County Regional Medical Examiner’s Office. The fleshed body (minus the neck
and head) was recovered first and accessioned into the Medical Examiner’s Office
for analysis. The seventh cervical vertebra was the most superior vertebra on these
remains. Sometime later, a skeletonized skull with the first six cervical vertebrae
was recovered and confirmed to belong to the body previously accessioned.
Soft tissue from the skull, seven cervical, and the first three thoracic
vertebrae was dissected and removed for anthropological analysis. Low power
magnification was used to examine the sixth and seventh vertebrae where narrow,
V-shaped cutmarks were found. The cut marks are consistent with a knife being
inserted from the anterior to posterior of the neck (Reichs, 1998). On the seventh
cervical vertebra there is a plane of sharp force trauma that extends across both the
left and right superior articular facets and across the uncinate processes of the
superior vertebral body. Additionally, perimortem fractures of the spinous
processes of both the sixth and seventh vertebrae were noted; these fractures are
suggestive of hyperextension of the neck following dismemberment (Ahn, 2011).
Introduction
Case Presentation
Both in the medicolegal and bioarchaeological literature,
decapitation is most common in the mid-neck, primarily between
C2-C5. This finding is likely due to 1) the anatomy in this area,
which makes it a weaker portion of the neck, and 2) the relative
exposure of the mid-neck in comparison to other aspects of the
body. The presence of vital blood vessels, like the common
carotid arteries and jugular veins, as well as the trachea makes it
an ideal location for intentional head dismemberment.
The next most common separation location was in the
superior portion of the neck. The superior portion of the neck
moves in a variety of ways including: 1) twisting; 2) flexion; 3)
extension; 4) rotation; and 5) forward or backwards; and 6) up or
down relative to inferior cervical vertebrae (Gomez, 2001:27).
The myriad range of movement is primarily due to distinctive
anatomical structures of C1 and C2. The C1 vertebra lacks a
vertebral body; has enlarged deeply concave superior articular
facets; and is essentially a ring where the occipital condyles
articulate to support the skull. Inferiorly to C1 is the C2 vertebra
which has a unique projection called the dens. The dens articulates
to the fovea on the interior aspect of the anterior arch. Both of
these structures and the lack of intervertebral discs allow for the
significant rotation of the superior neck. Unlike other vertebrae,
the skull, C1, and C2 move as a single unit (Moore et al., 2014),
which may make it more difficult to separate the head from the
torso. Although the superior portion of the neck is more mobile,
upper neck decapitations may also be difficult based on muscle
attachments at the base of the cranium (e.g., rectus capitis
posterior major and rectus capitis posterior minor), additional
ligaments (e.g., nuchal ligament, interspinous ligaments, cruciate
ligament, etc.), and membranes (e.g. tectorial membrane)
encountered between the cranial base, atlas, and axis.
In instances of lower cervical decapitation/dismemberment,
the prominent anatomical location of the seventh cervical vertebra
has been proposed as a reason for choosing the lower neck versus
the upper neck (Zoja et al., 2010). However, in the lower neck
region, the rhomboids and the transverse portion of the trapezius
may be encountered making separation of the head and neck more
difficult. The posterior aspect of the neck has approximately three
times more muscle than on the anterior portion, and consequently
the neck is three times stronger in extension than in flexion
(Gomez, 2001). Consequently, additional perimortem blunt force
trauma may also be present, such as in this case study where
hyperextension led to perimortem fractures (Figure 4). Fractures
associated with hyperextension typically occur at the weakest
point of the spinous processes (e.g. approximately 8mm from the
tip of the spinous processes) (Ayanoglu et al., 2017). The spinous
processes of the inferior cervical vertebrae are longer and have a
horizontal orientation which causes muscle loadings to be directed
perpendicular to the axis of the processes (Posthuma de Boer et
al., 2016). Thus, the hyperextension of the neck increases the
compression load on the posterior skeletal elements that will
eventually lead to the failure of the spinous processes.
As demonstrated in the literature, the most common
anatomical location of separation occurs at the weakest region of
the neck (C2-C5). The mid-neck region is relatively slender and
contains less soft tissue compared to the regions superior and
inferior to the second through fifth cervical vertebrae. The results
of the present study can aid the forensic and bioarchaeological
community in analyses of neck trauma associated with intentional
and accidental decapitation.
Discussion and
Conclusions
Results
Decapitation: A Case Study and Review of the Literature
Victoria Swenson1, Rebecca L. George 1, Marin A. Pilloud1and Laura D. Knight2,3
1Department of Anthropology, University of Nevada, Reno
2Washoe County Regional Medical Examiner’s Office, and 3University of Nevada,
Reno School of Medicine, Department of Pathology
Age
Accident
Homicide/
Dismemberment
Suicide
N/A
Fetal
-5
yrs
2 1 0 0
6-18 yrs 1 1 1 0
19
-
34 yrs
5 6 13 1
35
-50
yrs
7 2 14 1
51
-65
yrs
0 2 10 1
66+ yrs 1 2 1 0
N/A 10 13 3
Total: 26 27 42 3
Table 1: Age ranges of the 98 individuals included in this study.
Figure 1: Accident, homicide, and suicide demographics of the 98 individuals included in this
study.
Figure 2: Anatomical decapitation location of the 98 individuals presented in this
study.
2
1
5
7
0
1
10
1 1
6
2
0
1
13
14
10
1
3
0
2
4
6
8
10
12
14
16
FETAL-5.YRS
6-18.YRS
19
-34.YRS
35-
50.YRS
51-65.YRS
66+.YRS
N/A
Accident
Homicide /
Dismemberment
Suicide
N/A
2
13
1
11
2
4
9
12
1
20
15
28
2
23
10
0
5
10
15
20
25
30
ACCIDENTAL
HOMOCIDE/DISMEMBERMENT
SUICIDE
N/A
Skull-C2
C2-C5
C6-T1
Acknowledgments
We would like to sincerely thank Dr. Jenanne Ferguson from the University of
Nevada, Reno who translated an article necessary for this research.