A disc herniation is produced when part of the intervertebral disc placed between vertebrae displaces and presses against the nerve root that exits the spinal cord. This causes lesions of various types. This can be caused by falls, accidents, injuries... and degenerative changes of the spine among others.
In the cervical spine the most commonly affected places are the three last cervicals (C5-C6-C7). Some of the symptoms produced are: pain, muscle weakness, decrease in reflexes of arms and/or shoulders, etc.