Background and importance: Pedicle subtraction osteotomy (PSO) is a 3-column osteotomy used to correct rigid, large magnitude sagittal spinal deformity. PSO is an inherently destabilizing procedure intraoperatively, with high risk of neurological deficits from vertebral body subluxation or translation during osteotomy closure. Traditionally, PSO closure has been performed utilizing compression or cantilevering forces across adjacent level instrumentation. Such forces can loosen the instrumentation or cause abrupt subluxation or translation due to the magnitude of force required for PSO closure, resulting in neurological injury. Here, we report using a flexible hinge-powered operating table for controlled closure of PSO in 1º increments via remote-control power of the table, without compression or cantilevering force required across implants.
Clinical presentation: The patient is a 68-yr-old man with a history of prior L2-S1 anterior-posterior fusion, healed sacral fracture, and left sacroiliac joint fusion presenting to our institution with severe back pain while standing. X-rays demonstrated significant sagittal malalignment with pelvic incidence (PI) of 79º and lumbar lordosis (LL) of 37º, while computed tomography scan confirms complete bone healing around prior interbody fusion sites, resulting in rigid sagittal deformity. Due to rigid PI-LL mismatch of 42º, we planned for L2-pelvis revision fusion with L4 PSO.
Conclusion: Here we demonstrate the utility of a flexible hinge-powered operating table for closure of PSO site. This technique eliminates force application to adjacent implants, minimizing vertebral body subluxation, or translation. We believe this allows for safer, more controllable osteotomy closure that minimizes risk of neurological injury.
Keywords: PSO; Pedicle subtraction osteotomy; Spinal osteotomy.
Copyright © 2019 by the Congress of Neurological Surgeons.