Ethical dilemmas in skeletal collection utilization: Implications of the Black Lives Matter movement on the anatomical and anthropological sciences.

The Black Lives Matter (BLM) movement has brought to the public eye longstanding issues of social and racial injustice which have permeated the experiences of individuals of African ancestry in the United States and abroad for centuries. Motivated by a desire to disassemble a framework of systemic racism, the BLM movement has infiltrated numerous social and political arenas including the sciences, demanding change. The impact of the BLM movement is evident in the attention recently garnered by protests of museum skeletal collections' acquisition and handling of African/African American human remains. It is from this vantage point that we explore the ethical issues pervasive within United States skeletal collections and forensically relevant issues surrounding the unclaimed decedents of marginalized populations; colonial/imperial ideological formations, which construct and sustain power differentials in anatomization; and conceive of a path forward that prioritizes personhood.

Ancestry Studies in Forensic Anthropology: Back on the Frontier of Racism.

One of the parameters forensic anthropologists have traditionally estimated is ancestry, which is used in the United States as a proxy for social race. Its use is controversial because the biological race concept was debunked by scientists decades ago. However, many forensic anthropologists contend, in part, that because social race categories used by law enforcement can be predicted by cranial variation, ancestry remains a necessary parameter for estimation. Here, we use content analysis of the Journal of Forensic Sciences for the period 2009-2019 to demonstrate the use of various nomenclature and resultant confusion in ancestry estimation studies, and as a mechanism to discuss how forensic anthropologists have eschewed a human variation approach to studying human morphological differences in favor of a simplistic and debunked typological one. Further, we employ modern geometric morphometric and spatial analysis methods on craniofacial coordinate anatomical landmarks from several Latin American samples to test the validity of applying the antiquated tri-continental approach to ancestry (i.e., African, Asian, European). Our results indicate groups are not patterned by the ancestry trifecta. These findings illustrate the benefit and necessity of embracing studies that employ population structure models to better understand human variation and the historical factors that have influenced it.

Posterior femoral cutaneous neuropathy in piriformis syndrome: A vascular hypothesis.

Piriformis syndrome is described as a neuromuscular condition which occurs when the sciatic nerve is compressed and/or irritated by the piriformis muscle. It is characterized by acute tenderness in the buttock with sciatica-like pain radiating into the posterior aspect of the thigh, leg, and foot. The neurogenic leg and foot pain experienced with this condition is consistent with involvement of the sciatic nerve. However, the posterior thigh pain associated with piriformis syndrome is due to involvement of the posterior femoral cutaneous nerve (i.e., posterior cutaneous nerve of the thigh), which is a branch of the sacral plexus independent of the sciatic nerve. This nerve is rarely mentioned relative to piriformis syndrome even though posterior thigh pain is more prevalent in patients than leg and foot pain. In the few instances when the posterior femoral cutaneous nerve is referenced relative to piriformis syndrome the neuralgic signs associated with it are attributed to compression by piriformis. Yet, given the dramatic size difference between the sciatic and posterior femoral cutaneous nerves one would expect direct piriformis compression to impact the sciatic nerve first and produce leg/foot pain at a far greater frequency than posterior thigh pain. However, the opposite is seen in the literature, which raises the question, what underlying mechanism is responsible for this phenomenon? It is hypothesized that the prevalence of posterior femoral cutaneous nerve involvement in piriformis syndrome is due to compression of the inferior gluteal vein by a hypertrophied piriformis muscle.

The Use of Learning and Study Strategies Inventory (LASSI) to Investigate Differences Between Low vs High Academically Performing Medical Students.

OBJECTIVES: This study examines differences in the Learning and Study Strategies Inventory (LASSI) 10-subscale scores between low and high academically performing medical students relative to internal and external examinations. METHODS: The LASSI instrument was administered to 180 medical students from three classes (2016, 2017, and 2018). To measure the strength of association between LASSI 10-subscale scores and performance on overall biomedical sciences and the United States Medical Licensing Examination (USMLE) Step 1, Pearson product-moment correlation analyses were performed. One-way ANOVA and Bonferroni post-hoc analyses were performed to identify statistically significant differences on LASSI scores between students grouped by quartiles according to their performance on USMLE Step 1 examination (external performance measure) and by their average letter grade in the overall biomedical sciences (internal performance measure). RESULTS: Significant associations were observed between Anxiety, Motivation, and Test Strategies and students' performance on both overall biomedical sciences and USMLE Step 1 examinations. Anxiety, Motivation, and Test Strategies were different between "A" and "C" students in the overall biomedical sciences. Anxiety, Information Processing, Motivation, Selecting Main Idea, and Test Strategies were significantly different between the upper and lower quartiles in USMLE Step 1 student performance. CONCLUSIONS: Anxiety, Motivation and Test Strategies are the main LASSI subscales that were significantly different between high-performing and low-performing students for internal and external examinations. Interestingly, the same LASSI subscales Anxiety, Motivation, and Test Strategies were correlated with students' performance in internal and external examinations.

Utilizing Medical Students as Internal Assets to Enhance Gross Anatomy Laboratory Learning.

Identification of cadaveric structures during anatomy summative practical examinations is a challenge for first-year medical students. To assist in cultivating this skill, we offered 12 formative laboratory activities (anatomy boot camps [ABCs]) that approximated the summative practical examination format using reciprocal and near-peer teaching. Students assisted in crafting the formative practical examination, then engaged in a self-review by scoring their individual answer sheets. Students performing below designated thresholds (≤60%) were offered laboratory review sessions led by medical student upperclassmen. Mann-Whitney U tests were used to compare the performance of participants who attended the ABC sessions leading up to each summative examination. Correlation analysis was utilized to examine the relationship between student participation in ABCs summative examinations. Voluntary surveys were administered to assess the perceived value of the experience. Mann-Whitney U tests indicated students who attended the ABC review preceding three of the four summative practical and two of the four written examinations scored consistently higher on these examinations than students who chose not to attend. Correlation analysis revealed that as the overall frequency of ABC attendance increased, students' performance on the summative practical and written examinations increased significantly (P < 0.001). These findings suggest that the provision of supplemental learning experiences, such as the ABCs, contributes to improved student learning outcomes. This sentiment was echoed in student surveys. This activity, which combines multiple peer teaching approaches, appears to be an effective strategy for guiding and enhancing student success in the anatomy practical examinations. Clin. Anat. 33:286-292, 2020. © 2019 Wiley Periodicals, Inc.

Intrapartum lesions to the lumbar portion of the lumbosacral plexus: an anatomical review

The lumbosacral plexus is formed by the ventral rami of L2-S3 and provides sensory and motor branches to the lower extremity. The spatial orientation of the lumbar portion of the plexus above the pelvic brim leaves it particularly susceptible to intrapartum injury by the fetal head. Such lesions are subdivided into two groups: upper lumbar plexus (L1-L4) and lumbosacral trunk (L4-L5). Given the root levels involved, upper lumbar plexus lesions produce symptoms suggestive of iliohypogastric, ilioinguinal, genitofemoral, femoral, and obturator neuropathies or L4 radiculopathies. Alternatively, involvement of the lumbosacral trunk can imitate a common fibular (peroneal) neuropathy or L5 radiculopathy. This symptomatic overlap with various neuropathies and radiculopathies, makes diagnosis of such lesions particularly challenging. To assist in the clinical diagnosis of intrapartum lumbosacral plexopathies, we provide an overview of the motor, sensory, and reflex deficits associated with such lesions and establish the clinical profile of such patients by presenting case studies from the literature of lumbosacral plexopathies. Only cases from the literature involving women who delivered via cesarean section are explored to isolate the presentation of these lesions from injuries related to birth trauma.Based on this overview, we offer differential diagnostic tools which can be utilized to aid in the identification and subsequent treatment of intrapartum lesions to the lumbar portion of the lumbosacral plexus

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Learning and study strategies correlate with medical students' performance in anatomical sciences.

Much of the content delivered during medical students' preclinical years is assessed nationally by such testing as the United States Medical Licensing Examination® (USMLE® ) Step 1 and Comprehensive Osteopathic Medical Licensing Examination® (COMPLEX-USA® ) Step 1. Improvement of student study/learning strategies skills is associated with academic success in internal and external (USMLE Step 1) examinations. This research explores the strength of association between the Learning and Study Strategies Inventory (LASSI) scores and student performance in the anatomical sciences and USMLE Step 1 examinations. The LASSI inventory assesses learning and study strategies based on ten subscale measures. These subscales include three components of strategic learning: skill (Information processing, Selecting main ideas, and Test strategies), will (Anxiety, Attitude, and Motivation) and self-regulation (Concentration, Time management, Self-testing, and Study aid). During second year (M2) orientation, 180 students (Classes of 2016, 2017, and 2018) were administered the LASSI survey instrument. Pearson Product-Moment correlation analyses identified significant associations between five of the ten LASSI subscales (Anxiety, Information processing, Motivation, Selecting main idea, and Test strategies) and students' performance in the anatomical sciences and USMLE Step 1 examinations. Identification of students lacking these skills within the anatomical sciences curriculum allows targeted interventions, which not only maximize academic achievement in an aspect of an institution's internal examinations, but in the external measure of success represented by USMLE Step 1 scores. Anat Sci Educ 11: 236-242. © 2017 American Association of Anatomists.

Influence of edentulism on human orbit and zygomatic arch shape.

Edentulism, or tooth loss, seriously alters the appearance of the lower facial skeleton. The aim of this study was to determine if complete maxillary edentulism also impacts the curvature shape of the orbits and zygomatic arches in elderly adults. The study was conducted on 80 crania comprising two cross-sectional populations of elderly African- and European-Americans (60-80 years old). Forty of the crania possessed intact dentition; the remaining 40 exhibited complete edentulism with tooth socket resorption. Three-dimensional semilandmarks representing the curvature of the orbits and zygomatic arches were collected using a hand-held digitizer. Each craniofacial region's semilandmarks were aligned into a common coordinate system via generalized Procrustes superimposition. Regional variation in shape was explored via principal component analysis, multivariate analysis of variance, discriminant function analysis, cross-validation, and vector plots. Shape differences between the edentulous and dentate groups were detected in both the orbits (P = 0.0022) and zygomatic arches (P = 0.0026). Ancestry and sex differences were also identified in both regions. Orbit data correctly classified dentate crania 65% of the time and edentulous crania 72.5% of the time. Zygomatic arch data correctly classified 75% dentate and 60% of edentulous crania. The individual curves constituting each region also exhibited shape alteration with tooth loss, with the exception of the inferior zygomatic curve. Vector plots revealed patterns of superoinferior expansion, and medial and lateral recession depending on the region examined. These results suggest a relationship exists between maxillary edentulism and changes in the surrounding craniofacial structures.

Regional shape change in adult facial bone curvature with age.

Life expectancies have increased dramatically over the last 100 years, affording greater opportunities to study the impact of age on adult craniofacial morphology. This article employs a novel application of established geometric morphometric methods to examine shape differences in adult regional facial bone curvature with age. Three-dimensional semilandmarks representing the curvature of the orbits, zygomatic arches, nasal aperture, and maxillary alveolar process were collected from a cross-sectional cranial sample of mixed sex and ancestry (male and female; African- and European-American), partitioned into three age groups (young adult = 18-39; middle-aged = 40-59 years; and elderly = 60+ years). Each facial region's semilandmarks were aligned into a common coordinate system via generalized Procrustes superimposition. Regional variation in shape was then explored via a battery of multivariate statistical techniques. Age-related shape differences were detected in the orbits, zygomatic arches, and maxillary alveolar process. Interactions between age, sex, and ancestry were also identified. Vector plots revealed patterns of superoinferior compression, lateral expansion, and posterior recession depending on the population/subpopulation, location, and age groups examined. These findings indicate that adult craniofacial curvature shape is not static throughout human life. Instead, age-related spatial modifications occur in various regions of the craniofacial skeleton. Moreover, these regional alterations vary not only through time, but across human populations and the sexes.

Craniofacial growth, maturation, and change: teens to midadulthood.

Despite the attainment of several adult cranial dimensions relatively early in childhood, skeletal maturity and, by consequence, adult form are typically defined by the eruption of the third molars around 17 years of age. This in turn serves as the division between subadults and adults, which is then applied to population studies of biological variation. Specifically, comparative data sets of adult measurements are not directly applied to individuals who do not have complete skeletal growth, as it is believed that the confounding effects of allometry may skew the results. The present study uses geometric morphometrics techniques to investigate the appropriateness of this division with respect to three-dimensional anatomical landmarks. Twenty-six landmarks were collected from a single population of 24 crania partitioned into 4 age groups spanning late adolescence to midadulthood. Generalized Procrustes and multivariate statistical analyses were performed on the landmark data. Results showed no significant morphological differences between the teen and young adult age groups, whereas significant shape and size differences were found in older adults relative to their younger cohorts. Moreover, no growth-related shape variation (ie, allometry) was detected within the sample. These findings suggest that adult form is attained several years earlier than commonly thought and corroborate other research that suggest that subtle changes in cranial morphology continue throughout adulthood.