Since it is impossible to discuss all types of nerve root and spinal cord disorders in the time available, we have chosen to focus on the clinical features of syndromes caused by compression by tumors or other lesions affecting the nerve roots and the spinal cord.
http://www.neuroanatomy.wisc.edu/SClinic/Radiculo/Radiculopathy.htm
Spinal cord section with its ventral and dorsal root fibers and ganglion. Information from the skin, skeletal muscle and joints is relayed to the spinal cord by sensory cells located in the dorsal root ganglia. The dorsal root fibers are the axons originated from the primary sensory dorsal root ganglion cells.
http://neuroscience.uth.tmc.edu/s2/chapter03.html
The spinal nerve roots can be damaged as they traverse the spinal (vertebral) canal, but are especially vulnerable in the intervertebral foramina, where the ventral and dorsal spinal roots join to form the spinal nerves. Look over the segmental innervation of the lower and upper limbs in the following charts.
http://www.neuroanatomy.wisc.edu/SClinic/Radiculo/Radiculopathy.htm
Background. Cervical radiculopathy is a dysfunction of a nerve root of the cervical spine. The seventh (C7; 60%) and sixth (C6; 25%) cervical nerve roots are the most commonly affected. Sagittal magnetic resonance image of the cervical spine. This image reveals a C6-C7 herniated nucleus pulposus. In the younger population, cervical radiculopathy is a result of a disc herniation or an acute injury causing foraminal impingement of an exiting nerve. Disc herniation accounts for 20-25% of the cases of cervical radiculopathy.
http://emedicine.medscape.com/article/94118-overview
The spinal cord is the most important structure between the body and the brain. The spinal cord extends from the foramen magnum where it is continuous with the medulla to the level of the first or second lumbar vertebrae. It is a vital link between the brain and the body, and from the body to the brain. The spinal cord is 40 to 50 cm long and 1 cm to 1.5 cm in diameter. Two consecutive rows of nerve roots emerge on each of its sides. These nerve roots join distally to form 31 pairs of spinal nerves.
http://neuroscience.uth.tmc.edu/s2/chapter03.html
There are eight cervical nerve roots arising from the cervical spinal cord, which exit the vertebral canal through foramen (circular openings, or windows, between the vertebras that house the spinal cord). The size or diameter of the vertebral canal and foramen vary in size, depending on the person.
https://www.hss.edu/conditions_neck-cervical-nerve-spinal-cord.asp
Syndromes associated with lumbosacral radiculopathies. Posterior sciatica. * pain which radiates along the posterior thigh and the posterolateral aspect of the leg is due to an S1 or L5 radiculopathy (nerve roots). When caused by S1 irritation it may proceed to the lateral aspect of the foot; pain due to L5 radiculopathy may radiate to the dorsum of the foot and to the large toe.
http://www.neuroanatomy.wisc.edu/SClinic/Radiculo/Radiculopathy.htm
After exiting the canal, the lower cervical nerve roots become interwoven with each other to form the brachial plexus, a series of nerves that supply sensation and motor function to the arms and hands.
https://www.hss.edu/conditions_neck-cervical-nerve-spinal-cord.asp
These injuries occur from either a pinching (compression) of the nerve on the same side the neck is flexed/extended or a stretching of the nerve on the opposite side of where the neck is flexed/extended. Those affected may experience sharp, burning pain that may radiate into the shoulder and down the arm to the hand.
https://www.hss.edu/conditions_neck-cervical-nerve-spinal-cord.asp
The muscles in the neck support and protect the vertebral bodies, cord, and nerve roots by absorbing forces transmitted to the neck directly, or through the head or trunk.
https://www.hss.edu/conditions_neck-cervical-nerve-spinal-cord.asp
what is affected by cervical nerve root
Cervical radiculopathy is a dysfunction of a nerve root of the cervical spine.