(From the December 2006 The “G”Note)
When you see an obviously misaligned L4 on the AP x-ray, you’re probably dealing with an acute L5 subluxation. The L4 compensates to reduce pressure on the L5 disc. This results in an antalgic lumbar spine. This patient had a L5 PLI-M subluxation.
Don’t be fooled into thinking that L4 must be the subluxation due to the gross misalignment on the x-ray film. As Dr. Alex Cox states, “The subluxation isn’t free to move that far.”
This isn’t to say that a subluxation cannot demonstrate gross misalignment; it often does. That is why it is important to remember what Dr. C. S. Gonstead said: “Find the subluxation on the patient and verify it with the x-ray.”
Steven Tanaka, DC – Editor: It is easy to focus on a markedly misaligned vertebra on the x-ray film and declare that to be the subluxation to adjust. Dr. Vance presents pre- and post- AP x-rays of the lumbar spine to show the changes to the spine when the right subluxation is adjusted. In this case L5 was adjusted and L4 was left alone. When L5 was adjusted, the compensatory L4 alignment re-centered itself. As the saying goes, “fix the bad ones, and leave the good ones alone.”
Photo 1: initial x-ray. Note the tilt of L4 on L5 with the open wedge on the right side.
Photo 2: post x-ray. Note that the plane line of L4
is nearly parallel to the L5 plane line
“Find the subluxation. Accept it where you find it. Correct it. Leave it alone”. — C. S. Gonstead, D.C.