If there is a lower lumbar problem, one or both ilia will fixate in the AS positions. This is a self-protective mechanism, not to be lightly messed with. The problem is usually the lower lumbar spine with the ilia assuming the AS position, the sacral base will move posteriorly and superiorly to stabilize the spine. When the process goes too far, groin and hip discomfort will result. Reckless adjusting of the AS fixations can weaken the spine due to nutation.
Decisions based on knowledge have to be made.
If there is a left sided AS fixation, there is a lumbar problem predominant. Correct it first and then repalpate. If an AS fixation exists long enough, gluteal and hip flexors will become strained. If left uncorrected, secondary problems such as gluteal and hip flexor strain may become independent problems, requiring specific nonadjustive therapy. The lower lumbar extensors may also become strained.