obsolete_femur true The bone that extends from the pelvis to the knee, being the longest and largest bone in the body; its head articulates with the acetabulum of the hip bone, and distally, the femur, along with the patella and tibia, forms the knee joint. true Femoral os femoris os femorale Use http://purl.obolibrary.org/obo/UBERON_0000981 label: femur thigh bone NCIt:C12717 femoral bone 2.38 http://purl.obolibrary.org/obo/UBERON_0000981 The upper leg bone positioned between the pelvis and the knee. BTO:0001284 James Malone