Trepanations in non-adults of the 16th to 18th C. The osteological series of the Church of the Assumption of Valdepeñas (Ciudad Real, Spain).

OBJECTIVE: To investigate the presence of trepanations in an early Modern Age, skeletal collection documented in medical treatises but infrequently reported in osteological collections. MATERIALS: Analyses were conducted on 387 non-adult crania from the ossuary in the church of the Assumption of Valdepeñas (16th - 18th C.), Ciudad Real, Spain. METHODS: All complete or semi-complete crania of non-adults (aged 3-20 years) were macroscopically examined. RESULTS: Trepanation was detected in two adolescents aged 14 and 20 years; no evidence of their survival was observed. CONCLUSIONS: These findings suggest that trepanation was carried out in rural areas as Valdepeñas in the 16th-18th centuries, where the selection of instruments indicates knowledge of contemporaneous medical treatises. SIGNIFICANCE: The present study provides new data on trepanation and how it was performed in adolescents during this period. LIMITATIONS: Understanding the motive for these interventions is highly challenging in the absence of bone lesions, and their occurrence is likely underestimated due to the scant research in skeletal remains from the early Modern Age. SUGGESTIONS FOR FUTURE RESEARCH: Further palaeopathological analyses of osteological collections from this period will provide more information about how this surgical technique was perfected.

Estimation of the post-mortem interval of human skeletal remains using Raman spectroscopy and chemometrics.

An important demand exists in the field of forensic analysis to objectively determine the post-mortem interval (PMI) when human skeletal remains are discovered. It is widely known that bones undergo different chemical and physical processes after death, mainly due to their interaction with the environment in which they are found, although it is not known exactly what these processes consist of. Multiple techniques have been used so far to follow up these and other post-mortem changes and thus establish the time elapsed since the individual's death, but they present important drawbacks in terms of reliability and accuracy. The aim of this research was to propose an analytical methodology capable of determining the PMI by using non-destructive Raman spectroscopy measurements of human skeletal remains. The recorded Raman spectra provided valuable and potentially useful information from which a multivariate study was performed by means of orthogonal partial least squares regression (OPLSR) in order to correlate the PMI with the detected spectral modifications. A collection of 53 real human skeletal remains with known PMI (15 years ≤ PMI ≤ 87 years) was analysed and used for building and validating the OPLS model. The PMI of 10 out of 14 validation samples could be determined with an accuracy error of less than 30%, demonstrating the adequate predictive performance of the OPLS model even in spite of the large inter-individual variability it handled. This opens up the possibility of applying the OPLS model in combination with non-destructive techniques to the determination of the PMI of human skeletal remains that have been buried in conditions similar or equal to those of cemetery niches and in a geographic location with a Mediterranean climate, which is an important achievement for forensic medicine and anthropology.