The neck is the most critical of the spinal sections, since the spinal cord which transmits information from the brain to the body and back has not had a chance to start branching out into the peripheral nerves yet.  Thus it is fractures and abnormalities  here in the seven vertebrae that make up the cervical spine that most often result in paralysis, or even death.  It is also perhaps the easiest portion of the spine to injure since the seven vertebrae that make up the cervical spine are the smallest of the vertebrae and lack the the support structure that helps to protect the rest of the spine.  This is why paramedics will immediately place an auto accident victim in a cervical collar and strap them to a back board, especially since numerous studies have shown that the average accident victim is in too much emotional and physical shock to even know that they are in pain, let alone where they hurt.  If you've ever been in an accident yourself, think back to that accident.  Most likely you didn't feel any pain at all immediately after the wreck, yet 20 to 30 minutes later you felt like a you had been run over by a herd of wild horses.   If the doctor is only worried about major injuries to the neck, he or she will often order an AP (or frontal view) and a Lateral (or side view).  However because of the way the cervical spine connects to head and the body, two pictures will seldom do the job.  The side view is the picture that will most often demonstrate possible "unstable" fractures (those that are most likely to cause permanent problems if not handled correctly), yet because the neck connects to the upper back directly between the shoulders, a straight side shot will often not show all seven bones.  One way we can try to over come this problem is by having someone pull on the patient's arms, thus pulling the shoulders down and out of the way.  Yet even this method may not work completely.  I remember one man who had been a defensive lineman in college who's shoulders where so massive that even with our strongest assistant pulling on his arms, we could only see the top three bones.  In cases such as this, it is often necessary to do a second side shot using a position commonly called a "swimmers".  For this x-ray, the patient is commonly rolled up onto his or her side if it is safe to do so.  In either case, the arm closest to the film is raised up as high over the patient's head as possible, and the other arm is held stretched straight down the patient's side as if he or she was swimming (thus the common name for this position).   This has the effect of moving the shoulders up and down so that they are no longer superimposed on each other on the x-ray, thus giving us a better view of the spine as it runs between them.  Some technologists will also put a slight angle on the x-ray tube to help further separate the shoulders.

The next problem with x-raying the neck is getting a good frontal picture of all seven bones.  Between the slight forward curve of the cervical spine, and the jaw overhanging the top portion of the neck, it is necessary to put a slight angle on the x-ray tube to get a good picture of vertebrae 3 through 7.  In order to see the top two bones, which are directly behind your jaw, it is necessary to "play dentist" so to speak.  First we have the patient open his or her mouth as far as they can, then we try to align the patient's head so that neither the teeth nor the back of the head will be superimposed over these two bones (by the way, this x-ray is not always needed in young children since their heads tend to be shaped a bit differently and their jaws tend to be much thinner).  This should give us a clear image of the atlas (the top bone in the neck which connects with the head in such a way as to allow us to nod) and the odontoid (the second bone in the neck which has a "pin" sticking up called the dens which goes through a hole in the atlas and allows us to shake our heads).  An alternative to this open mouth x-ray is to align the x-ray beam with the angle of the jaw in such a way as to show the top two bones through the hole in the base of the skull where the spinal cord comes out.  While not as clear as the first picture, this extended Waters view is a viable alternative when the patient cannot do the open mouth version for one reason or another (i.e.- broken jaw, unusually long teeth, etc.).

Once the doctor has been satisfied that there is no immediate threat to the spinal cord, two obliques or angled shots are often done to demonstrate the IV (short for intervertebral) foramen where the various nerves come out of the cervical spine to run to the shoulders, arms, and chest.  Since these openings are at a 45 degree angle to the shoulders, the patient is rotated so that the shoulders form a 45 degree angle with the film holder first one way, then the other.  This allows the doctor and the radiologist to see if any of these holes are damaged in such a way as to put pressure on one of the nerves coming of the spinal cord in the cervical region.

The next portion of the spine is the thoracic spine which makes up the upper back.  The thoracic spine consists of twelve vertebrae which form the base to which the rib cage is anchored.  Because the rib cage gives some additional support to this area of the back, it is relatively unlikely for the thoracic spine to be broken, and when it is, the fracture is normally a compression fracture which means that the bone has been flattened or crushed.  An AP, or frontal view of the thoracic spine is a straight shot down through the patient's chest, with the center of the x-ray beam entering through the center of the sternum or breast bone.  The Lateral, or side view, can be a bit more difficult however.  For one thing, the patient's arms must be raised up as high as possible to avoid ending up with a picture of the patient's arms instead of an x-ray of the patient's back.  Still, this does not always show all 12 bones from the side.  As with the cervical spine, part of the thoracic spine is also located between the shoulders, thus making a "swimmer's" view identical to the one done for the neck necessary.  In fact the only difference between the two is that in the cervical version we are looking for the bottom most bone in the neck and part of the top bone in the upper back, while in the thoracic version we are looking for the top two or three vertebrae in the upper back and are only interested in the bones of the neck in so far as they are needed to be sure we know which vertebrae really is the top bone in the thoracic spine.  One other difference between the cervical vertebrae and the thoracic vertebrae is that the holes between the vertebrae where nerves come off of the spinal cord in the thoracic spine are parallel to the shoulders so additional views of the upper back are not needed to evaluate these IV Foramina for problems.

The lower back, or lumbar spine, is the next most likely portion of the spine to be injured next to the neck.  This is partly due to the fact that, like the cervical spine, the lumbar spine does not have any additional bony support like the thoracic spine does.  Instead, much of the support for the lower back relies on the size of the individual vertebrae and the abdominal muscles.  Add in the fact that the human back is designed to support weight with the back held straight as opposed to bent over, and you have lots of ways that you can injure your lower back without even realizing what happened until it is too late.  Fortunately the true spinal cord ends between the first and second lumbar vertebrae.  From this point down to the sacrum, the nerves contained by the lumbar spine resemble a bunch of fine delicate strands of hair, indeed one of the older names for this section is Latin for horse's tail since that is what it looked like to early scientists.  Because of this, fractures and injuries in the lower back are more likely to result in chronic pain and weakness rather than paralysis, but paralysis is still possible.  Where the lumbar spine connects to the sacrum and pelvic girdle, the spine starts to curve back which puts the joint between the bottom vertebrae in the lumbar spine and the sacrum at an angle to the plain that the rest of the lumbar vertebrae rest in.  However in most patients, L5 (the common short hand way of referring to the fifth or bottom most vertebrae in the lumbar spine) can be seen adequately in the plain frontal or AP and side or Lateral views that demonstrate the other four bones in the lower back.  However some facilities will take a "better safe than sorry" approach and include "spot" films (x-rays of the junction of L5 and S1 with the x-ray tube angled to match the angle of this joint) from the side, and possibly from the front as well.  When taking these x-rays, the technologist will feel for the crest or top of your pelvis and the bottom most rib to locate the center of your lumbar spine.  The positioning for the spot films if they are done uses the crest of the pelvis and the superior iliac spine (a raised portion on the front outer edges of the pelvis that can be easily felt in most patients).   Depending on the nature of your injury or problem, the doctor may also ask the technologist to get two obliques or angled shots in order to check out the articular processes which are small protrusions off the back of the lumbar vertebrae which help keep the lumbar spine aligned and help keep you from turning too far from side to side.   They are called articular processes because they articulate or form a moving joint with the processes of the lumbar vertebrae immediately above and below them.  To x-ray these processes, the technologist will have you roll up about 45 degrees to first one side, then the other.  The x-rays will be centered at about the level of the top of the pelvis and 1 1/2 to 2 inches in from the iliac spine.