Arumugan A, et al JOSPT Jan2012
Optimal LP stability is a function of form closure (FmCl), force closure (FcCl) and neuromotor control. Impairment can result in pain, instability, altered LP kinematics and changes in muscle strength and control. External pelvic compression (EPC) has been hypothesized to have an effect on FcCL and neuromotor control.
Conclusion: There is moderate evidence to support the role of EPC in decreasing laxity of the SI joint, changing LP kinematics, altering selective recruitment of stabilizing musculature and reducing pain.
There is limited evidence for the effects of EPC on decreasing sacral mobility.
Comment: So the effects of “SI” bracing are likely results of recruitment/firing pattern changes as opposed to simply added “support”…which is unlikely sufficient via a belt to add substantial mechanical alterations.
However the pelvis appears to have an “upper” & “lower” section either of which can be provocative or relieving in a bracing scenario in certain patients, i.e. some patients feel better with a tight belt at the pelvic brim, others with the support at the hip etc. The ATM2 has shown electrical quiescence of asymmetrical firing patterns with the use of its support belts. The assumption being IF “bad” or inefficient (painful) firing patterns/neuromotor control can be silenced via external bracing, the addition of painless exercise during the bracing appears to have great potential.