Both proximal femora from 10 females were acquired at autopsy. The trabecular component of the femoral neck of one specimen from each pair was evacuated, while the contralateral specimen was left intact as a reference. Bone mineral content (BMC) of the femoral neck, demonstrated only a slight (mean 4.8%) individual side to side variation. After evacuation of the trabecular component, BMC was reduced with mean 23.5%. Mechanical strength of the specimens, determined by applying a force to the femoral head perpendicularly to the axis of the femoral shaft, was reduced by mean 39.5%. Correlation between BMC and fracture strength was poor. There was no correlation between reduction in BMC and reduction in mechanical strength after evacuation, indicating that bone fracture strength is influenced by factors other than the mineral content.