midollari

Midollari, or the spinal cord, is a central nervous system structure that transmits information between the brain and the rest of the body and coordinates many reflexes. It extends from the medulla oblongata at the base of the brainstem down the vertebral canal to roughly the level of the first or second lumbar vertebra (L1–L2) in adults. Its length is about 42 to 45 centimeters, and the spinal cord is shorter than the vertebral column, with nerve roots continuing as cauda equina below the conus medullaris.

Anatomically, the spinal cord consists of gray matter at the center, shaped like a butterfly, surrounded by white matter tracts. The gray matter contains neuronal cell bodies and synapses, organized into dorsal (posterior) and ventral (anterior) horns, with lateral horns present in thoracic and upper lumbar regions for autonomic neurons. The white matter consists of ascending and descending myelinated axons organized into funiculi (posterior, lateral, and anterior). The cord is divided into spinal segments—cervical, thoracic, lumbar, and sacral—each giving rise to a pair of spinal nerves that exit through the intervertebral foramina. The conus medullaris marks the tapering end, and the filum terminale extends to the coccyx to anchor the cord.

Blood supply is provided mainly by the anterior spinal artery and two posterior spinal arteries, with segmental medullary arteries reinforcing the circulation. Venous drainage occurs via the internal vertebral venous plexus. Functionally, the spinal cord carries motor commands from the brain, conveys sensory information to the brain, mediates most reflexes, and houses neural circuits involved in locomotion and autonomic control. Developmentally, it originates from the neural tube and is organized into segments that align with vertebral correspondences, though adult spinal length lags behind the length of the vertebral column.