Frederic Savall

Reliability of the Suchey-Brooks method for a French contemporary population

The Suchey-Brooks method is commonly used for pubic symphyseal aging in forensic cases. However, inter-population variability is a problem affected by several factors such as geographical location and secular trends. The aim of our study was to test the reliability of the Suchey-Brooks method on a virtual sample of contemporary French males. We carried out a retrospective study of 680 pubic symphysis from adult males undergoing clinical Multislice Computed Tomography in two hospitals between January 2013 and July 2014 (Toulouse and Tours, France). The reliability of the Suchey-Brooks method was tested by the calculation of inaccuracy and bias between real and estimated ages, and the mean age for each stage and the mean stage for each 10-years age interval were compared. The degree of inaccuracy and bias increased with age and inaccuracy exceeded 20 years for individuals over 65 years of age. The results are consistent with an overestimation of the real age for stages I and II and an underestimation of the real age for stages IV, V and VI. Furthermore, the mean stages of the reference sample were significantly lower for the 14-25 age group and significantly higher for individuals over 35 years old. Age estimation is potentially limited by differential inter-population error rates between geographical locations. Furthermore, the effects of secular trends are also supported by research in European countries showing a reduction in the age of attainment of indicators of biological maturity during the past few decades. The results suggest that the Suchey-Brooks method should be used with caution in France. Our study supports previous findings and in the future, the Suchey-Brooks method could benefit from re-evaluation of the aging standards by the establishment of new virtual reference samples.

Geometric morphometric analysis reveals sexual dimorphism in the distal femur.

An individuals sex can be determined by the shape of their distal femur. The goal of this study was to show that differences in distal femur shape related to sexual dimorphism could be identified, visualized, and quantified using 3D geometric morphometric analysis. Geometric morphometric analysis was carried out on CT scans of the distal femur of 256 subjects living in the south of France. Ten landmarks were defined on 3D reconstructions of the distal femur. Both traditional metric and geometric morphometric analyses were carried out on these bone reconstructions; these analyses identified trends in bone shape in sex-based subgroups. Sex-related differences in shape were statistically significant. The subjects sex was correctly assigned in 77.3% of cases using geometric morphometric analysis. This study has shown that geometric morphometric analysis of the distal femur is feasible and has revealed sexual dimorphism differences in this bone segment. This reliable, accurate method could be used for virtual autopsy and be used to perform diachronic and interethnic comparisons. Moreover, this study provides updated morphometric data for a modern population in the south of France.

Virtual anthropology: useful radiological tools for age assessment in clinical forensic medicine and thanatology.

Virtual anthropology consists of the introduction of modern slice imaging to biological and forensic anthropology. Thanks to this non-invasive scientific revolution, some classifications and staging systems, first based on dry bone analysis, can be applied to cadavers with no need for specific preparation, as well as to living persons. Estimation of bone and dental age is one of the possibilities offered by radiology. Biological age can be estimated in clinical forensic medicine as well as in living persons. Virtual anthropology may also help the forensic pathologist to estimate a deceased person’s age at death, which together with sex, geographical origin and stature, is one of the important features determining a biological profile used in reconstructive identification. For this forensic purpose, the radiological tools used are multislice computed tomography and, more recently, X-ray free imaging techniques such as magnetic resonance imaging and ultrasound investigations. We present and discuss the value of these investigations for age estimation in anthropology.

Three-dimensional geometric morphometric analysis reveals ethnic dimorphism in the shape of the femur

BackgroundEthnic dimorphism in the distal femur has never been studied in a three-dimensional analysis focused on shape instead of size. Yet, this dimorphism has direct implications in orthopedic surgery and in anthropology. The goal of this study was to show that differences in distal femur shape related to ethnic dimorphism could be identified, visualized, and quantified using 3D geometric morphometric analysis.MethodsCT scans of the distal femur were taken from 482 patients who were free of any bone-related pathology: 240 patients were European (E) and 242 were Asian (A). Ten osteometric landmarks based on standard bone landmarks used in anthropometry were placed on these scans. Geometric morphometric analysis, principal component analysis (PCA), canonical variates analysis (CVA), and other discriminant analyses (Goodall’s F-test and Mahalanobis distance) were performed. A cross-validation analysis was carried out to determine the percentage of cases in which the ethnicity was correctly estimated.ResultsThe shape of the E and A distal femur differed significantly (Goodall’s F = 94.43, P < 0.001 and Mahalanobis D2 distance = 1.85, P < 0.001). PCA identified a difference in distal femur shape between A and E. The CVA revealed that correct ethnicity was assigned in 82% of cases and the cross-validation revealed a 75% rate of correct ethnic group estimation.ConclusionThe distal femur exhibits ethnic dimorphism. 3D geometric morphometric analysis made it possible to demonstrate these differences. The large number of subjects studied has helped modernize the references for certain bone measurements, with direct implication for orthopedic surgery and anthropology.

Old hearts for modern investigations: CT and MR for archaeological human hearts remains

INTRODUCTION Among 800 burials dated between the 15th and 18th centuries and found in the center of Rennes (Brittany, France), a collection of five heart-shaped lead urns was discovered. This material was studied using classical methods (external study, autopsy and histology), and also modern imaging like computed tomography (CT), magnetic resonance (MR) before and after coronary opacification. The aim of this manuscript is to describe different steps of ancient soft tissues study, especially using imaging techniques. METHODS The study gathered various specialists: anthropologists, archeologists, forensic pathologists, radiologists, pathologic physicians, and physicists. Imaging techniques were performed, before and after coronary opacification. Finally, hearts were autopsied and different histological samples were analyzed. RESULTS Only heart n°2 was too damaged to be studied. Heart n°3 was considered as normal using all investigation techniques. The study of Hearts n°s 4 and 5 revealed dilated cardiomyopathy while Heart n°1 showed important signs of diffuse hypertrophic cardiomyopathy. Different fibro lipid plaques were identified using imaging techniques, and were confirmed by histology. CONCLUSIONS The study of archeological soft tissues using modern imaging is possible if the material is well-preserved. This type of research can uncover principal findings, allowing scientists to establish diseases of ancient times.

Technical note: A preliminary comparative study between classical and interventional radiological approaches for multi-phase post-mortem CT angiography

PURPOSE Multi-phase post-mortem computed tomography angiography (MPMCTA) is a new diagnostic tool, used in forensic pathology. On the one hand, this technique allows a better and direct visualization of vascular and solid organ lesions. On the other hand, the invasiveness of the procedure-which requires surgical denudation (inguinal and/or cervical) and the insertion of surgical cannulas-leads to many relatives refusing scientific autopsies. Our hypothesis states that a minimally-invasive procedure combining interventional radiological techniques with MPMCTA (replacement of surgical cannulas by radiological catheters) will improve the approval rate of scientific autopsies by families. The aim of this study was to evaluate the feasibility of the minimally-invasive MPMCTA approach and to compare its performance to the current reference-standard (the conventional approach). MATERIAL AND METHODS We included consecutively 16 corpses divided in two groups according to the contrast enhancement approach: radiological catheters (n=8), and surgical cannulas (n=8). Corpses were chosen and assigned randomly from our local data. The quality of the imaging procedure was compared according to four items: global vascular opacification, cerebral venous opacification, and lower limbs opacification (arterial and venous). RESULTS A minimally-invasive approach for scientific autopsies is feasible through a radiological catheter. Vascular opacification was optimal in 8 out of 8 cases and was no less effective than the control reference group using surgical cannula incision associated with their non-occlusive aspects.

An unusual homicidal stab wound of the cervical spinal cord: A single case examined by post-mortem computed tomography angiography (PMCTA)

We report an unusual case of homicidal stab wound of the cervical spinal cord, which illustrates the value of post-mortem computed tomography angiography (PMCTA) in cases of vascular injury. First, we noted a posterior and horizontal trajectory to the neck with complete section of the cervical spinal cord between the first and second cervical vertebrae. This lesion was accompanied by section of the right vertebral and right deep cervical arteries. We also noted an anterior cervical trajectory with an injury to the right internal jugular vein and an anterior right chest wound with a lung trajectory and section of the internal mammary vessels. Cases of spinal cord injuries secondary to stab wounds are rare in the literature. Only one large series has been published from Cape Town. Complete section of the cervical spinal cord accounts for only 4.5% of all cases. Furthermore, lethal cases are rare and classically victims survive and present neurological sequelae. We found only one similar case but despite the transection of the cervical spinal cord the patient survived. Some studies suggest that PMCTA may be very helpful in visualizing vascular system injuries. Our observations are consistent with this proposal. The use of different-time acquisitions was essential for detection of the injured vessels.

Sex determination of a Tunisian population by CT scan analysis of the skull

It is widely accepted that the estimation of biological attributes in the human skeleton is more accurate when population-specific standards are applied. With the shortage of such data for contemporary North African populations, it is duly required to establish population-specific standards. We present here the first craniometric standards for sex determination of a contemporary Tunisian population. The aim of this study was to analyze the correlation between sex and metric parameters of the skull in this population using CT scan analysis and to generate proper reliable standards for sex determination of a complete or fragmented skull. The study sample comprised cranial multislice computed tomography scans of 510 individuals equally distributed by sex. ASIRTM software in a General ElectricTM workstation was used to position 37 landmarks along the volume-rendered images and the multiplanar slices, defining 27 inter-landmark distances. Frontal and parietal bone thickness was also measured for each case. The data were analyzed using basic descriptive statistics and logistic regression with cross-validation of classification results. All of the measurements were sexually dimorphic with male values being higher than female values. A nine-variable model achieved the maximum classification accuracy of 90% with −2.9% sex bias and a six-variable model yielded 85.9% sexing accuracy with −0.97% sex bias. We conclude that the skull is highly dimorphic and represents a reliable bone for sex determination in contemporary Tunisian individuals.

Comment on: Systematic Review and Meta-Analysis of Occupational Outcomes After Bariatric Surgery

Dear Editor, We read with great interest the systematic review of Sharples and Cheruvu about occupational outcomes after bariatric surgery [1]. We congratulate the authors for their interesting work. The relationship between obesity and occupation raises a major public health issue. Obesity surgery is very powerful to improve quality of life. The authors pointed out the limited evidence in the literature regarding occupational outcomes following bariatric surgery. They demonstrated that bariatric surgery has a generally positive impact on occupational outcomes. This implies that surgery may have wider economic, social, and psychological benefits over and above its immediate health benefits [1]. We would like to add to authors’ conclusions, since their systematic review only identified ten studies, which compared occupational outcomes before and after surgery, between 2004 and 2015. We have identified 15 more studies [2–16], and we have chosen to include other surgical procedures (open surgeries, adjustable gastric banding, vertical banded gastroplasty) and older articles (from 1977 to 2016), because we cannot ignore the successive evolutions of bariatric surgery and the successive evolutions of work world. All studies published between 1977 and 2000 showed an increase in employment after surgery by 17–29% [2–5]. Furthermore, Peace et al. [6] observed that 36% of the operated patients had better occupational functioning, and Valley et al. [7] observed that 33% of their sample improved their educational or occupational status within the first postoperative year by taking courses, gaining employment, or advancing their occupational status. Crisp et al. [8] found that at 2 years after surgery, 30% of a nonworking sample had taken up a full-time job. Martin et al. [9] found increases in rates of employment in a publicly funded group: approximately 45% of those receiving public assistance could decrease their level of support. All these studies compared employment before and after surgery. Näslund and Agren [10] compared, at 1 year, operated patients to controls (those seeking bariatric surgery). OBES SURG (2017) 27:811–812 DOI 10.1007/s11695-016-2487-3

Candida albicans spondylodiscitis following an abdominal stab wound: Forensic considerations

Candida albicans spondylodiscitis is a fungal infection of the spine which is still unusual in spite of the increasing frequency of predisposing factors. A 22-year-old man received an abdominal stab wound during a physical assault. Initial medical care included surgery, prolonged use of indwelling vascular catheters with administration of broad-spectrum antibiotics, and hospitalization in intensive care. Two months after the event, the victim experienced back pain in the right lumbar region and septic spondylodiscitis secondary to C. albicans was diagnosed three weeks later. This case is noteworthy because of its clinical forensic context. In France, the public prosecutor orders a medico-legal assessment after an assault for all living victims in order to establish a causal relationship between the assault and its complications. In our case, the patient presented numerous risk factors for candidemia and the forensic specialist reasonably accepted that the causal relationship was certain but indirect. We have only found one published case of spondylodiscitis after an abdominal penetrating injury and the pathogenic agent was not mentioned. We have found no case reported in a forensic context. This unusual observation shows that it may be genuinely difficult to prove the causal relationship between an abdominal penetrating injury and an unusual infectious complication such as fungal spondylodiscitis.