Rectus abdominus monitoring during Deep Neck Flexor Training - Really?

It is normal to monitor sternocleidomastoid, anterior scalenes and the hyoids during the cranio-cervical flexion test (CCFT). As well of course, the pattern of flexion. When the superficial muscles have increased activity and the deeper longus coli (and rectus capitis anterior & lateralis) are not producing as much flexion, the head will move into a retraction pattern rather than flexion.


Not everyone has good motor skill learning abilities. There are essentially 3 categories of motor skill learning.
1: Cannot learn (neurocognitive, sensorimotor deficits with neurological soft signs)
2: Can learn with difficulty and extra time
3: Good learners

When teaching the CCFT, a small number of people appear to do very good - almost too good for their first try. But the MCAQ does not predict they would be very good learners. On palpation, there is no palpable activity of the superficial muscles as all. A closer inspection of the pattern reveals they use thoracic flexion. This has the ability in a small number of people to lever the head into flexion. This will generally only occur if you are doing the test on a first low friction surface (e.g. phone book).

So if someone appears to do the test very well with no superficial muscle activity at all, it is worth palpating rectus abdominis just below the zyphoid process.

This can be avoided by doing a motor imagery assessment during the teaching phase of the CCFT. 

Notes:
The MCAQ is a very accurate tool for screening motor skill learning ability.
Primitive reflex inhibition can be used to rehabilitate movement and motor skill learning in poor learners

Everyone should be familiar with this reference:

Martin-Gomez C, Sestelo-Diaz R, Carrillo-Sanjuan V, Navarro-Santana MJ, Bardon-Romero J, Plaza-Manzano G. Motor control using cranio-cervical flexion exercises versus other treatments for non-specific chronic neck pain: A systematic review and meta-analysis. Musculoskelet Sci Pract. 2019 Jul;42:52-59. doi: 10.1016/j.msksp.2019.04.010.