The OMT intervention included a brief physical examination to identify somatic dysfunction in lumbar, pelvic, sacral, and lower extremity body regions that treating physicians (C.L.R. or C.R.E. and K.T.S.) considered relevant to the participant's asymmetry of the sacral base position and SSD. Treating physicians were blinded to findings of the US measurements. The OMT was performed to improve sacral asymmetry by treating the sacrum and surrounding regions (lumbar, pelvis, and lower extremities). Improvement in sacral asymmetry was verified (K.T.S.) prior to the postintervention US. The OMT techniques included 1 or more of the following: muscle energy, articular, or high-velocity, low-amplitude as indicated by physical findings and discretion of the treating physician. Additional techniques, such as Still, counterstrain, facilitated positional release, balanced ligamentous tension, and osteopathic cranial manipulative medicine, could be used at the discretion of the treating physician, but total treatment time could not exceed 20 minutes. To encourage participation in the initial study, participants assigned to seated control could receive OMT after the postintervention US assessment.