OK, given those 2 scenarios given by stcommodore:
Case 1: Theoretically should be fully immobilized. They have an AMS which makes you unable to assess for neuro deficits. Though, nothing will probably save this guy, the discussion is purely academic. However, scene is unsafe. As far as I am concerned scoop and run. Sorry dude, my life over yours (at least if you have any left).
Case 2: Does not need a cervical collar. He is neurologically intact. No one is making jusdgements about a long board to keep the rest of the spine secure. There seems to be some confusion about what immobilization means. The c-collar only immobilizes the cervical spine. If you have a localized injury to the thoracic cord, a c-collar will do nothing to protect it.
Reread what the PHTLS book says:
In general, if a patient did not sustain definite neurologic injury at the moment that the trauma occurred, there is little concern for a spinal injury. This is because of the mechanism of injury and the kinematics associated with the force involved. Penetrating objects generally do not produce unstable spinal fractures as does blunt force injury because penetrating trauma produces little risk of unstable ligamentous or bony injury.
Penetrating injuries do not cause unstable spinal fractures. Therefore there is no potential for cord damage following the injury due to the patient moving. Any cord damage is going to happen at the time of the injury and will manifest immediately. Interested in a little EBM, here is an article to review:
http://www.ncbi.nlm.nih.gov/sites/entrez?D...Pubmed_RVDocSum
There were 57,532 patients that were evaluated at the two trauma centers. Of those, 42.3% (24,336) were following blunt or penetrating assault. All of the penetrating injury patients with a cspine fracture or cervial spinal cord injury had some form of neurologic deficit on presentation. There was one blunt assault patient who presented without neuro deficit, but he had neck pain at the time of presentation. All patients with cervical spinal cord injury had a neuro deficit on presentation.
Here is one more for you:
http://www.ncbi.nlm.nih.gov/sites/entrez?D..._RVAbstractPlus
Here is one that discusses putting the pt on a board:
http://www.ncbi.nlm.nih.gov/sites/entrez?D..._RVAbstractPlus
Here is one that I found interesting, though I'm not too sure how I feel about it yet:
http://www.ncbi.nlm.nih.gov/sites/entrez?D..._RVAbstractPlus