The sacrum is the name of the bone located at the base of the spine that consists of five fused vertebrae. The sacrum is anatomically present between fifth lumbar vertebrae and the coccyx. S1 vertebral body 2.S1 nerve root 3.Thecal sac 4.Sacral ala 5.Sacroiliac joint, synovial portion 6.Iliac crest 7.Median sacral crest 8.Inferior L5-S1 facet joint 9.Ligamentum flavum 10.Sacroiliac joint, fibroligamentous portion 11.Multifidus muscle 12.Erector spinae muscle group 13.Gluteus medius muscle 14.Gluteus minimus muscle 15. https://www.spineuniverse.com › anatomy › lumbar-spine-sacrum-coccyx It is triangular-shaped bone present between the two hip bones. 1. The lumbosacral spine is that section of the backbone which lies around the level of the lower back and hips. The sacrum (or sacral bone, latin: os sacrum) is a triangular bone at the base of the spine, which is formed by five sacral vertebrae (S1 - S5) that fuse with each other between ages 18 and 30. The sacrum and coccyx are unlike other bones in your spinal column. The sacrum, sometimes called the sacral vertebra or sacral spine (S1), is a large, flat triangular shaped bone nested between the hip bones and positioned below the last lumbar vertebra (L5). In this article, we shall look at the anatomy of the sacral plexus – its formation and major branches. The alae (wings) of the sacrum articulate bilaterally with the ilium. The superior aspect of the sacrum, referred to as the sacral promontory, articulates superiorly with the L5 vertebral body of the lumbar spine. Sacral bone is located at the lower part of the vertebral column. Whilst the internal spinal cord only stretches down as far as the the L2 vertebrae, damage to the sacral region can still have a range of different effects. Below the lumbar area is the sacral region, commonly called the base of the spine. Within the spine, an individual bone is known as a vertebra, plural vertebrae. https://www.innerbody.com › image_skel05 › skel14_spine.html The sacrum itself sits between the fifth segment of the lumbar spine (at the level of L5) and the coccyx (the tail bone). The sacrum articulates with four bones - with the last (fifth) lumbar vertebra … S1 vertebral body level. This arrangement forms the lumbosacral joint, which is reinforced by iliolumbar and lumbosacral ligaments. Anatomy of the human Spine. A discussion of the anatomy of the sacral spine is best considered in light of the traumatic and surgical implications related to surgical fixation in sacral fractures and elective spine … Understanding sacral dysmorphism is critical for the safe placement of lumbosacral and iliosacral fixation. The plexus is formed by the anterior rami (divisions) of the sacral spinal nerves S1, S2, S3 and S4. It also receives contributions from the lumbar spinal nerves L4 and L5. The sacrum is basically made up of …