11. The nerve growth factors were given to rats whose nerve roots had been crushed. 12. Thus, a C5 / 6 disc hernia will normally affect the C6 nerve root . 13. Hunsicker said additional tests last week showed there was pressure on a nerve root . 14. These symptoms are compatible with a spinal cord or nerve root contusion, said Ordia. 15. If the L5 nerve root is involved, the most common cause is a herniated disc. 16. Foraminal stenosis at this joint is the most common cause of cervical nerve root pressure. 17. "Basically, ( the MRI showed ) that where the nerve root comes out, it's pinched," 18. These nerve roots are called according to the spinal vertebrata which they are adjacent to. 19. This procedure is usually performed when decompression of more than one nerve root is needed. 20. Dermatomal distributions are lines on the skin surface following the distribution of spinal nerve roots .