Spinal cord injuries: Paraplegia: paralysis of both lower limbs Quadriplegia: paralysis of all 4 limbs  Complete transection: loss of all sensations and voluntary movement below the level of transection  Hemisection: partially severed – paralysis on the side of cut “Challenges are often a matter of our perception."

Part of CNS Found within vertebral foramina of all vertebrae (for protection) extends to 3 rd or 4 th lumbar vertebrae Location

Function The pathway for sensory input to the brain and motor output from the brain Reflex center

Spinal cord anatomy

Spinal nerves: path of communication between spinal cord and specific parts of body; come in pairs  Connected to spinal cord by: Posterior (dorsal) root – sensory neurons; contains a posterior root ganglion (containing cell bodies of neurons) Anterior (ventral) root – motor neurons In the back; Out the front

Gray matter  forms a butterfly shape in the white matter  dendrites, cell bodies, unmyelinated axons

Anatomy of gray matter Central canal: center of gray matter; filled with cerebrospinal fluid Posterior (dorsal) horns: sensory neurons Anterior (ventral) horns: somatic motor neurons In the back; Out the front

Anatomy of white matter Columns: contain tracts – bundles of axons; to/from brain

Meninges 3 layers that surround brain and spinal cord for protection  Dura mater: most superficial  Arachnoid mater: middle  Pia mater: touches surface of spinal cord and brain. Cerebrospinal fluid is between arachnoid and pia mater. It cushions and carries nutrients (oxygen, glucose) to neurons