This is a fluoroscopy of a subject from the study back in 2008. The subject is turning their head to the left and there iliac crest raises slightly. The subject had a positive Asymmetrical Tonic Neck Reflex (ATNR) with apparent leg length shortening on the right when the cervical spine was turned to the left.

There are numerous implications of a positive  ATNR including:

  • muscle tone changes in the trunk (e.g., quadratus lumborum, oblique abdominals, psoas major)
  • biomechanical loading implications
  • apparent “leg length discrepancy” observations (many other primitive reflexes can be involved)
  • scoliosis (as documented in children)
  • motor control rehabilitation of the trunk, shoulder girdle, cervical spine

It doesn’t really matter what school of thought you follow, it is pretty easy to see there are implications for primitive reflexes. If primitive reflexes are present, they can be treated with primitive reflex inhibition and motor behavior can improve.

The study in question was looking at the influence of head and limb positions that mimicked primitive reflexes on pattern of abdominal hollowing. The link for this is here:

“Effect of head and limb orientation on trunk muscle activation during abdominal hollowing in chronic low back pain”. https://pubmed.ncbi.nlm.nih.gov/24558971/

It was based on the clinical observations I had for many years on abdominal hollowing. I wrote this paper on asymmetry in abdominal hollowing.

Retraining of asymmetry in recruitment of transversus abdominis

https://www.researchgate.net/publication/262912493_Retraining_of_asymmetry_in_recruitment_of_transversus_abdominis

Primitive reflexes are very gentle and easy techniques to do. They are very useful for helping people move better, and improve motor control. For others (who require a neurological approach), they are a critical aspect of treatment (e.g. concussion, neurodevelopmental disorder, strong neurological soft signs).