Biomechanical analysis of a femur fracture in osteoarchaeology: Reconstruction of pathomechanics, treatment and gait.

In paleopathology, biomechanics allows us to investigate traumas in ancient skeletal remains. The aim of our current research is to reconstruct pathomechanics, treatment and gait of an individual from a Late Medieval femur with evident bone callus. In particular, to reconstruct the dynamic of the trauma that caused the injury and the adopted therapeutic measures, taking into account medical knowledges of that time. The femur was recovered during the archaeological investigation in the Sanctuary of Sacro Monte, Varese (Northern Italy). Classical physical anthropological methods and CT scans were used for macroscopic and radiological measurements of the bone. Finally, the reconstruction of the static and dynamic functional outcomes of the lesion were performed by Observation Gait Analysis (OGA) procedure. The femur shows an important callus at the middle third proximal of the shaft. The antemortem fracture was oblique and caused by a direct trauma probably related to occupational activities. The alignment of the segments in the frontal plane lead us to assume that the fracture was treated and the femur was immobilized with splints. The overlap and the angle of the segments indicate that the subject was not submitted to traction or fracture reduction. Good bone remodeling and consolidation of the fracture suggest that the subject had gradually led to the resumption of load and walking, although with important effects on posture and movement. The use of the OGA allows us to highlight the subject's kind of gait after healing.