Variation of the anterior aspect of the femoral head-neck junction in a modern human identified skeletal collection.

The effectiveness of the so-called skeletal markers of activity as functional indicators is widely debated. Among them, certain morphological features of the anterior aspect of the femoral head-neck junction (Poirier's facet, cervical fossa of Allen, etc.) have been considered in relation to some behaviors and specific activities (e.g., squatting, horseback riding, etc.). However, disagreement on terminology and descriptions, the absence of standardized scoring methods and poor knowledge of the variability and distribution of these features make it difficult to interpret their meaning. The aim of this study is to analyze the variability of the anterior aspect of the femoral neck through a new scoring method taking into account three main traits: Poirier's facet, plaque, and cribra (including the Allen's fossa). This method has been applied to a sample of 225 adult individuals of both sexes coming from an identified modern skeletal collection, achieving low intraobserver and interobserver error values. The results highlight some significant trends: plaque, almost always bilateral, appears to be a normal condition of the femur, being present in approximately 90% of the individuals. Cribra is more frequent in females and decreases with age. Poirier's facet shows a very low frequency. This method allows the representation of both the anatomical diversity of the region already described in literature and part of the variability never considered before. Our results suggest caution in considering these features as markers related to specific activities.