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.
A normal healthy cervical spine has a slight lordotic curve and it is anatomically important to bear the weight of head. Loss of cervical lordosis can result in straightening of cervical spine or in severe cases it can reverse the curve. The condition is also called cervical kyphosis.Loss of cervical lordosis can result in pain and stiffness in neck. Injury to cervical spine may also lead to loss of cervical lordosis. 2  A whiplash while driving motor vehicle, direct trauma on the neck can all contribute to muscle spasm and loss of curvature of cervical spine. 3  Osteoporosis is another important factor that may cause abnormality in cervical spine curvature.