Sagittal plane correction in pedicle subtraction osteotomy using the Xia 3 SUK Direct Vertebral Rotation System:...

The Xia 3 SUK Direct Vertebral Rotation (DVR) System was developed for performing the vertebral derotation maneuver in scoliosis surgery. The author applied this device to sagittal plane correction in pedicle subtraction osteotomy for adult spinal deformity. The surgical procedure included 1) preparing secure proximal and distal foundations for correction using mutisegmental pedicle screw-rod fixation (to avoid stress concentration to a specific screw-bone interface), 2) decancellating only the posterior two-thirds of the vertebral column, 3) providing supplemental interbody fusion above and below the osteotomy site (the anterior one-third of the vertebral column and interbody cages serve as an anterior column support and a pivot of correction), 4) closing the osteotomy by gradual approximation of SUK tubes secured to the proximal- and distal-most screw heads, and 5) connecting rods between the proximal and distal screw-rod constructs. Eight consecutive patients with fixed sagittal imbalance were treated using this surgical procedure. No patient required distal fixation points extending to the sacrum and/or pelvis. The sagittal plane correction was 43°. The mean anterior deviation of the C-7 plumb line was improved from 12.7 cm to 4.0 cm immediately after surgery, and it was 6.0 cm at the final follow-up. A pedicle subtraction osteotomy using the Xia 3 SUK DVR System ensures a safe and secure sagittal plane correction in adult spinal deformity.