Open dataset of femoral cross-sectional geometry across ontogeny, including high resolution CT-derived structural variables, estimated ages, and proteomic sex identification.

Ontogenetic changes in long bone structure provide critical insights into the interplay between growth, mechanical loading, and skeletal development, yet open-access datasets focusing on non-adult individuals remain limited. This study presents an open dataset of femoral cross-sectional geometric properties spanning infancy to adolescence, derived from high-resolution computed tomography (CT) scans of archaeological human remains from the San Pablo Convent (Burgos, Spain). The dataset includes 72 unfused femora representing a continuous developmental sequence from 2.00 to 16.18 years of age. Cross-sectional geometric variables were extracted at four standardized and biomechanically meaningful locations along the femur: distal diaphysis, midshaft, proximal diaphysis, and femoral midneck. For each section, the dataset provides measurements of cortical and medullary areas, area ratios, second moments of area, and torsional rigidity, enabling detailed assessments of structural strength and biomechanical adaptation during growth. Age at death was estimated primarily from dental development, with complementary femoral-length-based regressions when dentition was unavailable. A key feature of this dataset is the inclusion of biological sex estimation based on amelogenin peptide identification from tooth enamel using a minimally invasive proteomic approach, allowing the investigation of sexual dimorphism prior to skeletal maturity. This resource supports reproducible research in bioarchaeology, biomechanics, and developmental skeletal biology.