According to the American Academy of Orthopaedic Surgeons, or AAOS, neck pain can be caused by abnormalities in the soft tissues, including the muscles, ligaments and nerves, along with the vertebrae or spinal bones and joints. In some cases, neck pain manifests on only one side of the cervical spine and radiates to the upper shoulder area. Neck and shoulder pain can be mild, moderate or severe, depending on the cause of the pain.
Whiplash can cause right-sided pain that runs from the neck down to the shoulder. According to the National Institute of Neurological Disorders and Stroke, or NINDS, whiplash is a collection of symptoms that occur immediately after a rapid extension and flexion injury of the neck. In most cases, whiplash involves a neck sprain and strain -- soft tissue injuries that can cause considerable pain or discomfort in one or both sides of the neck, depending on the orientation of the neck during the injury. The most common cause of whiplash is a motor vehicle accident, although the condition can also be caused by sports mishaps. Common signs and symptoms associated with whiplash include neck pain that radiates to the upper shoulder, neck stiffness, headaches, dizziness, numbness and tingling in the arms, back pain, memory loss, impaired concentration, nervousness and irritability.
Brachial Plexus Injury
A brachial plexus injury can cause pain on the right side of the neck down to the shoulder. Brachial plexus injuries involve damage to the network of nerves -- the brachial plexus -- that send signals from the spine to the shoulder, arm and hand. Brachial plexus injuries occur when these nerves are stretched or torn. Brachial plexus injuries may occur when the head and neck are forcibly moved away from the affected shoulder while the affected shoulder is pressed down, over-stretching the side of the neck and the tissues that run from the upper neck to the top of the shoulder. According to MayoClinic.com, brachial plexus injuries are common in contact sports, but may also occur during motor vehicle accidents and falls. Common signs and symptoms associated with brachial plexus injuries include neck and shoulder pain, an electrical shock-like sensation down the arm and affected-side arm numbness and weakness.
Cervical Disc Herniation
According to the Spine Universe website, a ruptured or herniated cervical disc is a common cause of neck, shoulder and arm pain. A cervical disc herniation occurs when the annulus fibrosus -- the fibrous ring that surrounds a spinal disc -- cracks or breaks open, allowing the nucleus pulposus -- the jelly-like center portion of the spinal disc -- to protrude into the spinal canal or the intervertebral foramen. The intervertebral foramen is the hole through which spinal nerve roots -- offshoots of the spinal cord -- exit the spinal column. If the herniated disc material irritates or compresses one of these nerve roots, a person will usually experience pain or discomfort in the neck, shoulder and arm. Along with pain, common signs and symptoms associated with a cervical disc herniation include arm numbness and tingling and weakness in certain arm muscles.