Differential Diagnosis – Bracer vs Releaser (The table to the left delineates these two extremes.  However, most patients lay somewhere in between.)

Bracer denotes an extreme state of increased muscular tonus (hypertonicity).  Releaser denotes an extreme state of decreased muscular tonus (hypotonicity).  Since muscles act in chains (not independently), a tonicity change in a specific muscle reflects a tonicity change in the entire chain.

Elevating or lowering of the inner longitudinal arch reflects tonicity changes within the posterior chain.  The posterior and anterior chains interact in a reciprocating fashion.  That is, when the posterior chain is braced, the anterior chain is released.  When the posterior chain is released, the anterior chain is braced.