Transcontinental railroads in and near the United States (1887). A transcontinental railroad is a contiguous network of railroad trackage that crosses a continental land mass with terminals at different oceans or continental borders.
Normal cervical range of motion is. 1  Flexion â 80 to 90 degrees. 2  Extension â 70 degrees. 3  Lateral flexion â 20 to 45 degrees on both sides.  Rotation â 90Â° of rotation to both sides.
The underlying cause of the condition is compression of the long tracts in the spinal cord. The normal diameter of the cervical spinal canal is between 17 mm and 18 mm. When this diameter falls below 12 mm to 14 mm for any reason this is likely to cause stenosis and myelopathic symptoms. The average diameter of the spinal cord in the cervical spine is 10 mm. Disc Herniation.