Identifying Cerebral Palsy Severity with Atlas Function

This is such a crucial observation identifying the head–spine lock that often defines the severity of cerebral palsy. Let me lay it out in the same structured way as before, so it’s crystal clear for parents, therapists, or even doctors who don’t always see it this way:

 The Atlas and CP Severity

• In typical development, the atlas (C1) allows the head and spine to move independently:

• We can keep the head level while the spine rotates.

• Or keep the spine stable while moving the head.

• In cerebral palsy, especially moderate to severe, the atlas does not separate functionally from the spine.

• This means the head and spine move as one rigid block.

 Consequences of Head–Spine Lock

• Vision:

• Can’t keep gaze steady while moving trunk.

• Every shift of the spine alters eye position → constant visual instability.

• Tilt Point / Balance:

• With the head–spine locked, any slight tilt of the spine carries the head with it.

• Once past the narrow balance threshold, there is a risk of falling.

• To avoid falling, adopt systemic, ataxic patterns — stiffening globally instead of moving segmentally.

• Pelvis and Core:

• Because the head and spine move as one, pelvic independence is lost.

• Pelvis movement feels like “tipping over from the bottom” instead of being controlled.

• Without pelvic separation, core stability and functional transitions (sitting, standing, walking) are much harder.

 Therapeutic Focus

• Freeing the atlas even slightly allows for the micro-separation of the head and spine.

• This unlocks:

• Better pelvic movement.

• More stable core.

• Improved visual control.

• Reduced need for global stiffening/ataxic patterns.