Injuries to the neck may originate with the bones of the cervical spine, the disks present in the spinal column, the spinal cord, the nerves that extend into the neck, or the muscles that work with the cervical spine to create movement.
The neck is generally described as the region of the human anatomy that extends from the base of the skull to the top of the shoulders. It is supported by the cervical spine, a portion of the backbone that is a series of seven vertebrae, semicircular bones that are assembled into a column. Between each vertebrae is a disk, a ring-shaped fibrous structure that is designed to assist in the absorption and cushion of the shocks received by the spine.
The vertebrae are connected to one another by facets, ligaments that permit the various vertebrae to flex in movement. The cervical vertebrae are constructed to permit the head and the neck to move the head forward, backward, and in rotation. Vertebrae are designated in accordance with their position in the spine; the cervical, or neck, vertebrae are numberd C1 through C7, with the C1 vertebrae being the structure that supports the skull.
The vertebrae are shaped to provide bone protection to the spinal cord, which extends from the brain through the length of the spine; the brain and the spinal cord are the components of the central nervous system. From the spinal cord emanate nerves from individual openings in each of the vertebrae, extending into the body to create the network of muscular control and direction that is the peripheral nervous system. A serious injury to the spinal cord has the potential to ultimately compromise the entire peripheral system.
The muscles that work most closely with the cervical vertebrae to provide movement are the splenius capitis, which is positioned on both sides of the neck along the spine, and the trapezius, the muscles that connect the base of the neck to the shoulders.
The neck is subjected to a number of direct traumas in many different sports. The most common types of sport injuries that involve either the neck of the cervical spin include:
- Fracture of the cervical spine: This serious injury most commonly arises when the athlete has the neck driven forcefully into the shoulders. Common mechanisms of this injury are a football tackle, when either the ball carrier or the tackler has his/her head driven in a compressive fashion into the cervical vertebrae, which are forced into one another. This fracture may also occur when a diver strikes his/her head upon either the bottom of a swimming pool, or if he/she is diving from a significant height, where the diver's head collides with the water surface at an acute angle.
- Whiplash: This is an injury that may occur in similar circumstances to those of a cervical fracture. Whiplash most commonly is the result of the body moving and then coming to a sudden stop, with the head and neck continuing to move forward in a violent motion. Whiplash is a common outcome of collisions in sports such as auto racing, ice hockey, American football, and other contact sports. The reverse of the whiplash mechanism occurs, to the same physical effect, when a boxer is punched to the head, causing the skull and neck to be forced backward, while the rest of the body is relatively stationary. Unlike a fracture, whiplash is a soft tissue injury.
- Pinched nerve: This is the generic term used to describe a circumstance when one of the components of the nerve network that extends from the spinal cord becomes the subject of pressure, often from physical contact. The pressure prevents the nerve from functioning correctly, which may create a loss of function in the muscle serviced by the nerve.
- Disk injury: As with any other part of the back, the disks that separate the cervical vertebrae may become irritated, or the disk may become herniated, where its gel content leaks out and creates pressure upon the adjacent nerves. The herniated disk can occur as a result of a single movement, such as a strenuous lift, or the condition may arise over time through repeated stresses to the neck or poor posture.
- Spinal cord: An injury to the spinal cord is usually the most serious neck injury. Spinal cord damage usually occurs along with a significant force or impact. When the spinal cord becomes severed, the person will almost always lose the function of either the lower limbs (paraplegia), or all of the the limbs, (quadriplegia).
Improper technique in contact sports is the leading cause of cervical spine and neck injuries in sport. When the athlete is either instructed to initiate contact with the head, or when they are reckless in the manner in which their head is exposed to such contact, neck injuries are a far more probable outcome. American football, where all players wear a helmet that in some circumstances accentuates this risk, and ice hockey, where the athletes are subject to being driven into a the barrier surrounding the playing surface, are each higher risk sports for a neck injury.