A vertebral column consists of vertebrae described as belonging to Pentad groups (known as segments). These segments come (sequentially from either top to bottom): a cervical, thoracic, & lumbar vertebrae, & a sacrum and coccyx.

Embryology
In the man fetus, the spinal cord extends all the way down to the sacral vertebrae. As a individual matures, a spinal cord shortens relative to a rest of a system, therefore at adulthood, a spinal cord lone reaches down to in the level of L1 (the number one, i personally.e. greatest, lumbar vertebra), where it ends & a cauda equina begin - this is why lumbar punctures are commonly carried out in an adult at a (moo) level of L3/L4.

Anatomy
A spinal cord originates within a brain at the inferior prevent of the medulla oblongata, exiting the skull via the foramen magnum. These are wrapped around troika shells of membranes, known as meninges.

A spinal cord carries sensory signals and motor innervation to most of the skeletal muscles in the body. About each voluntary muscle in a body beneath the head depends on the spinal cord for control. Likewise, virtually all cutaneous sensation in a image below a neck is transmitted via the spinal cord. Virtually all of the sympathetic pathways and the moo (we.e. non-vagal) parasympathetic pathways also go through the spinal cord.

The cross-subdivision through the spinal cord reveals that there is a exchange canal (carrying spinal fluid - CSF) surrounded by grey matter on the inside, & this is surrounded by white matter. (This is the opposite to the brain's cerebral cortex.) A part of the cord may be divided into great symmeterical halves per dorsal median sulcus & ventral median fissure.

A dorsal (towards a back) side of the spinal cord carries centripetal principles. A nerve cell that bring somatosensory info to the spinal cord reside in the dorsal root ganglion. Sensation from either a moo person travels higher a willowy tract, sensation from either a upper person & arms travels higher a wedge-shaped tract, which lies lateral to the willowy tract. No wedge-shaped tract in a lumbar a portion of the spinal cord when receptive reference from either the arms would non travel across this metropolitan area.

Drive facts (signals from either a brain to move a muscles) travels down a ventral (some the stomach) half of the spinal cord. Motor neurons are within a front tooth (this means about a front, in homo it means the equivalent when ventral) horn of the gray matter. There are ii independent columns of nerve cell in a prior horn, the medial & lateral drive columns.

A actual cord is approxiamately cylindrical in shape, but a across varies at different vetebral levels. There are deuce enlargements, cervical & lumbar. A cervical enlargement is due to a cord segments from either C3 to T1 which innervates a upper limb via the brachial plexus. A lumbar enlargement arise from segments L1 to S3 & innervates a moo limbs via a lumbar & sacral plexuses.

A spinal cord proper stops at a level of L1. It ends at a conic point called the conus medullaris, from either which a strand of connective tissue, the filament terminale extends caudal & attaches to the dorsal surface of the foremost cocygeal vertebra.

There is a higher proportion of substantia alba in the cervical (neck) part of the spinal cord. This is because references to & from either a whole system (like a feet) must pass across on this text. Around counterpoint, a lumbar & sacral areas don't carry trading tools from either anywhere above the children, and so develop less substantia alba.

Pathology
Damage in the spinal cord, known as myelopathy, can symptom inside paraplegia or quadriplegia, depending on a level inside the spinal cord of the damage. spinal tumor syringomyelia