If you are a practitioner who routinely evaluates sacroiliac function during standing hip flexion, you should notice the loss of sacroiliac motion on one or both sides following lumbar spinal injury, dysfunction or degeneration.
Counternutation is the posterior motion of the sacral base which occurs during anterior superior motion of the ilium (PSIS point of reference). In other words, the body tries to decompress the posterior aspect of the lumbar spine with the anterior superior ilia or ilium fixation relative to a posterior sacral base.
Because of this compensatory fixation, it can be exacerbating when the practitioner completes an AS ilium fixation adjustment. The result will certainly cause posterior ilium motion and anterior sacral base motion, decompensating the spine. This is particularly concerning in cases of disc injury, severe inflammation or facet syndrome.
(When more stable at later stages, an AS ilium adjustment can be the right thing to do to relieve further pressure, a topic of discussion for another article.)
If there is ilium motion blockage during standing hip flexion accompanied by complaints, and when various adjustments and procedures have not released the ilium motion blockage, you may want to look at lumbar traction with decompression as the treatment tool. This could include formal computerized "spinal decompression" or flexion traction methods. In monitoring SI joint motion during hip flexion while standing, after all other methods are tried, it is not uncommon to find a release of SI fixation following decompression traction. The release may be slight to very significant in measurement of PSIS motion.
In cases of obvious significant disc or facet injury, other spinal or sacroiliac corrections by adjustment or otherwise may obviously be avoided, and you may choose to begin immediately with decompression traction. You may find blocked SI motion will be unblocked following traction.
Dr. Joseph Kurnik practices in Torrance, Calif. He is a former columnist and longtime contributor to DC; previous articles are available online at www.dynamicchiropractic.com.