A compression of C3 and C4 means that the vertebrae or nerves in the midsection of the cervical spine, near the base of the neck, are compressed. Injuries that impact the nerves and tissue in this upper spinal region are the most severe because they cause the most damage to the body’s central nervous system. Compression of spinal cord nerves can result in temporary quadriplegia, a form of paralysis, until swelling subsides or a spinal decompression procedure is performed.