Many joints are not fused a birth. These include the skull as well. This allows for rapid growth and maturation of the boney skeleton.
The sacrum is formed by the fusion of five vertebrae.
sacrum, it's actually five bones that are fused together.
Sacrum, and Coccyx
The five bones fused in the lower back are called the sacrum. The sacrum is a triangular bone located between the two hip bones and forms the back part of the pelvis. It is made up of five separate vertebrae that fuse together during development.
Sacrum
The pelvis is three bones (ilium, ischium, and pubis) fused together. So is the sacrum which are five vertebrae fused together into one bone. The frontal bone (forehead) begins life as two separate bones that seamlessly fuse together as well.
The two sections of the spine that consist of fused bones are the sacrum, which is formed by the fusion of five sacral vertebrae, and the coccyx, which is formed by the fusion of four coccygeal vertebrae.
The pelvis is formed of 3 fused bones: the illium, ishium, and pubis. The sacrum is formed of 5 fused bones. And the coccyx is formed of 2-4 bones.
They are the bones at the bottom of your spine. Often called the tailbone it is the fused section of 3-5 bones below the sacrum.
Five components fused together are typically referred to as a compound or a blend.
The five fused vertebrae with which the hip bones move are collectively known as the sacrum. The sacrum forms the posterior wall of the pelvis and connects the spine to the hip bones, providing stability and support for the body.
The human spine contains 33 bones, including the 24 vertebrae, 9 fused vertebrae in the sacrum and coccyx, and the skull base known as the sacrum.