Investigating femoral growth disruption in subadults from the 10th-13th century St. Étienne cemetery of Toulouse, France.

OBJECTIVES: The skeleton embodies an individual's environment and lived experiences. Studying childhood growth disruption can, therefore, aid in understanding the experiences of children in the past. This study evaluates growth disruption in a medieval Toulousian subadult sample to explore factors that may have influenced childhood growth and mortality at this site and to assess the utility of Harris line (HL) interpretations in bioarchaeology. MATERIALS AND METHODS: Femoral growth disruption was assessed in n = 71 subadults (0.125-12.42 years) from the 10th-13th century St. Étienne cemetery of Toulouse, France, using femoral length, total area, cortical area, and relative cortical area. Femoral radiographs were assessed for HLs. To determine the prevalence of growth disruption, z-scores were calculated using data from the Denver growth study. RESULTS: The majority of subadults in this sample suffered from femoral growth disruption. Young children (1.0-3.99 years) were the most affected, with >65% experiencing reduced appositional growth and linear growth stunting at time-of-death. Additionally, while many individuals presented with observable HLs, linear and appositional growth did not significantly differ between individuals with and without HLs. DISCUSSION: Maternal malnutrition and inadequate complementary feeding practices likely contributed to the high prevalence of growth disruption among the youngest individuals in the study. The older children and adolescents buried at St. Étienne experienced an amelioration in growth deficits, indicating an improvement in nutrition and/or disease load. The results of this study suggest that more consideration is required when interpreting the presence/absence of HLs, and that studies assessing HLs may benefit from using a more individualistic approach.

Precarious adolescence: Adolescent rickets and anterior sacral angulation in two Dutch skeletal collections from the 18th-19th centuries.

OBJECTIVE: This project aims to provide an objective approach to suggesting cases of adolescent rickets using the presence of anterior sacral angulation and interglobular dentine. MATERIALS: Sacra from 49 individuals from Hattem and 150 individuals from Middenbeemster, and second and third molars from five individuals from Hattem were analyzed. Both sites date to the 17th to 19th centuries. METHODS: The sacra were visually assessed for sacral angulation and measured to quantify anterior sacral angulation. The sampled molars were thin sectioned to look for the presence of interglobular dentine. RESULTS: Metric analysis determined that seven individuals had significantly anteriorly angled sacra. Three of the five individuals with sampled molars had interglobular dentine formed during adolescence. CONCLUSIONS: Adolescent rickets may be associated with anterior sacral angulation. SIGNIFICANCE: Anterior sacral angulation may help identify possible cases of adolescent rickets in archaeological human remains. LIMITATIONS: The small sample size for the molars prevented the identification of more individuals with interglobular dentine present during adolescence. Several individuals with visibly angled sacra were unmeasurable due to post-mortem damage and lacked molars. SUGGESTIONS FOR FURTHER RESEARCH: Research on a larger sample would allow us to understand better the association between anterior sacral angulation and adolescent rickets.

Is dietary deficiency of calcium a factor in rickets? Use of current evidence for our understanding of the disease in the past.

OBJECTIVE: Rickets is considered an indicator of vitamin D deficiency in palaeopathology, but a strand of biomedical thought maintains that dietary calcium deficiency may sometimes play a part in its causation. Our aim is to evaluate the extent to which low calcium intake should be considered as a factor in biocultural interpretations of rickets. METHODS: We assess published modern epidemiological studies that provide primary data to support claims for a role for dietary calcium deficiency in rickets. We also consider how we might identify, via indicators of calcium intake, populations at risk of calcium deficiency in the past. RESULTS: Support for dietary calcium deficiency as a cause of rickets is equivocal. Direct measurement of dietary calcium in the past is not possible, but exposure to risk factors for low calcium intake can to some extent be identified. CONCLUSION: Whilst there is little evidence to alter the view that rickets is essentially an indicator of a population's vitamin D status, occasionally, in very low calcium intake groups, dietary calcium deficiency may play a synergistic role by accentuating the need for vitamin D. SIGNIFICANCE: The notion that dietary calcium deficiency may be a cause of rickets appears to be gaining currency in bioarchaeological studies. This paper shows that it is unusual for this to be the case, and even then the role of vitamin D remains crucial. LIMITATIONS: This paper attempts to summarise the current state of biomedical study in an area that is subject to continuing investigation.

An Investigation of Micro-CT Analysis of Bone as a New Diagnostic Method for Paleopathological Cases of Osteomalacia.

OBJECTIVE: This paper looks to broaden the methodological possibilities for diagnosing osteomalacia in archaeological bone using micro-CT analysis. Increasing the identification of osteomalacia in paleopathology will provide support for important interpretive frameworks. MATERIALS: Nine embedded and two unembedded rib fragments were sourced from St. Martin's Birmingham and Ancaster, UK, and Lisieux Michelet, France. Of the 11 samples, nine were previously confirmed as osteomalacic, and presented with varying levels of diagenesis and two were non-osteomalacic controls, one of which exhibits diagenetic change. METHODS: Micro-CT, backscattered scanning electron microscopy, and light microscopy were employed. Micro-CT images were evaluated for osteomalacic features using corresponding microscopic images. RESULTS: Micro-CT images from osteomalacic samples demonstrated the presence of defective mineralization adjacent to cement lines, areas of incomplete mineralization, and resorptive bays/borders, three key diagnostic features of osteomalacia. Diagenetic change was also detectable in micro-CT images, but did not prevent the diagnosis of osteomalacia. CONCLUSIONS: Micro-CT analysis is a non-destructive method capable of providing microstructural images of osteomalacic features in embedded and unembedded samples. When enough of these features are present, micro-CT images are capable of confirming a diagnosis of osteomalacia. SIGNIFICANCE: Vitamin D deficiency has important health consequences which operate throughout the life course. Increasing the ability to detect cases of vitamin D deficiency provides researchers with a greater understanding of health and disease in past communities. LIMITATIONS: Only adult rib samples were used. SUGGESTIONS FOR FURTHER RESEARCH: Paleopathologists should look to test the utility of micro-CT analysis in diagnosing active rickets in subadult individuals.