The spinal column is a very complex structure made up of vertebrae, discs, joints, ligaments, nerves and muscles.  This structure is very intricately interconnected so it should not be a surprise that an injury to one portion of this complex structure can cause pain in another part of the structure.  Therefore, injuries or problems with the neck can definitely be a contributing factor to back pain.  A pinched nerve or a pulled muscle in the neck area can extend down into the back and cause back pain.