Whenever an official injury diagnosis includes the words "spinal cord," as in the case of Jameel McClain's injury, everyone takes pause.
As scary as that sounds, doctors expect McClain to make a full recovery, and surgery will not be required.
Nevertheless, spinal cord contusions sound scary for a reason.
The information highway from the brain to the rest of the body, the spinal cord runs from the top of the neck to the lower back. It carries the electrical signals from the brain to the muscles, organs and tissues of the body.
Partial or complete interruption of the pathway at any point causes symptoms below the level of injury. Those symptoms include, but are not limited to weakness, numbness and, in the worst-case scenario, complete and permanent paralysis.
Interruption of the spinal cord occurs when it is compressed or severed. Severance of the cord produces the most catastrophic consequences, but compression from a contusion can cause just as much damage.
Fortunately, McClain's injury appears to be of a much, much milder variety.
Let's take a look at what probably happened.
When McClain went down during the Baltimore Raven's Week 14 31-28 loss to the Washington Redskins, the force of the blow to his neck likely ruptured some of the blood vessels surrounding his spinal cord.
When blood vessels break, they bleed. Unlike a simple cut to the skin that bleeds into the outside world, blood from broken vessels on the inside of the body has nowhere to go. Instead, it collects in a small pocket of blood called a "hematoma."
A growing hematoma displaces the other tissues surrounding it. In McClain's case, those tissues included the spinal cord.
Swelling from injury to ligaments surrounding the spinal cord leading to cord compression can also cause a contusion.
Exact medical details remain unavailable, so it is unclear which type of injury best describes McClain's case. Fortunately, reports of serious symptoms have not surfaced, suggesting that the contusion is only slightly pressing on his spinal cord.
Regardless, any degree of spinal cord contusion is quite serious. Though doctors project a full recovery, McClain must rest until then.
It takes time for McClain's body to heal by absorbing the swelling or bleeding of the contusion.
Until it does, additional injury could result in further swelling or bleeding, and therefore, more spinal cord compression. More spinal cord compression has the potential to lead to the dire consequences discussed above.
During the coming weeks and months, McClain will likely undergo MRIs at regular intervals to monitor the resolution of the swelling or hematoma. He will also be subjected to frequent neurological testing to evaluate sensation and muscle strength throughout his body.
When McClain's MRI no longer shows evidence of contusion and his neurological exam shows normal and symmetrically intact sensation and muscle strength, he will likely resume physical activity.
Assuming symptoms do not recur as his activity level is gradually increased, he will then return to NFL action.
Unfortunately, this process of healing and medical clearance will take a significant amount of time, and team physicians will certainly be safe rather than sorry.
Though NFL players frequently play through mild injuries, when an injury is to the spinal cord or brain, there is zero room for error.
McClain's negative neck X-rays from Week 14 are not enough to allow him to play, as X-rays allow doctors to look at only the bones of the neck.
MRIs show soft tissue detail, such as that of muscles, ligaments or the spinal cord itself. When McClain's MRI showed spinal cord damage, he was immediately ruled out despite a clean X-ray.
Speculation suggests that further evaluation showed the contusion to be large enough to merit placing McClain on Injured Reserve, as Wilson also reports.
This move thins out an already injury-depleted Baltimore Ravens defense, and the Ravens (9-5) suddenly look vulnerable.
Yet the Ravens are not alone. They merely represent the next victim of an injury-ravaged 2012 NFL season.
Whether or not further reform takes place to address the ever-increasing amount of injuries being sustained by NFL players is a conversation for another time.
Nevertheless, McClain's spinal cord contusion represents the most recent serious injury suffered in the NFL.
Unless something changes, Roger Goodell's league faces substantial problems in the future regarding this issue.
Dave Siebert is a medical/injury Featured Columnist for Bleacher Report who will be graduating from medical school in June, 2013. He has plans to specialize in both Family Medicine and Primary Care (non-operative) Sports Medicine. Injury and anatomical information discussed above is based on his own clinical knowledge and was supplemented a transcript of Dr. David Wong's interview on spinal cord contusions that can be found here.