Sacrum apex is directed downward and presents an oval facet for articulation with the coccyx. The sacral canal as a continuation of the vertebral canal runs throughout the greater part of the sacrum. The sacral angle is the angle formed by the true conjugate with the two pieces of sacrum. Normally it is greater than 60 degrees. A sacral angle of lesser degree suggests funneling of the pelvis. The sacral promontory marks part of the border of the pelvic inlet, and comprises the iliopectineal line and the linea terminalis. The sacral promontory articulates with the last lumbar vertebra to form the
Artificial bone fractured bone. However, if damage to bone is caused by a disease or severe injury, it becomes difficult for the body to repair itself. When the human body is unable to regenerate the lost bone tissue, surgeons come in and replace the missing bone using autografts, allografts, and synthetic grafts (artificial bone). When compare artificial bone to autograft and allograft, it is less invasive and more biocompatible since it avoids the risk of unknown viral infections. When designing implanted biomaterials, key criteria are biocompatibility, osteoconductivity, high porosity and biomechanics compatibility. Artificial bone was initially made of materials like metals and