A patient support structure includes a pair of independently height-adjustable supports, each connected to a patient support structure. The supports may be independently raised, lowered, rolled or tilted about a longitudinal axis, laterally shifted and angled upwardly or downwardly. Position sensors are provided to sense all of the foregoing movements. The sensors communicate data to a computer for coordinated adjustment and maintenance of the inboard ends of the patient support structures in an approximated position during such movements. Longitudinal translation structure provides for compensation in the length of the structure when the supports are angled upwardly or downwardly. Patient translation structure provides coordinated translational movement of the patient's upper body along the respective patient support in a caudad or cephalad direction as the support structures are angled upwardly or downwardly for maintaining proper spinal biomechanics and avoiding undue spinal traction or compression.