Transitional vertebrae have the characteristics of two types of vertebra. The dural sac ends at the vertebral level of the second sacral vertebra. The lumbar cistern extends into the sacrum upto S2 vertebra. Each thoracic nerve T1 -T12 originates from below each corresponding thoracic vertebra. Adjacent to each vertebra emerge spinal nerves. The sacrum is a normal block vertebra. Anterolisthesis commonly involves the fifth lumbar vertebra. The underside of the second sacral vertebra has an angular longitudinal keel. One passenger suffered a compression fracture to his first lumbar vertebra. Its most prominent point behind corresponds to the spinous process of the seventh thoracic vertebra. The accident left her with a fractured lumbar vertebra and damaged nerves in her legs. It enters the root of the left lung opposite the sixth thoracic vertebra. They then proceed superiorly, in the transverse foramen of each cervical vertebra. Inclination begins to decrease at the ninth thoracic vertebra. Spondylolisthesis is the displacement of one spinal vertebra compared to another.