Factors Leading to Revision Surgery after Percutaneous Vertebroplasty Using Hydroxyapatite Block and Posterior Fusion for Osteoporotic Vertebral Fracture: A Retrospective Study

<p>Introduction: The rate of reoperation due to screw backout is high after posterior fusion (PSF) combined with percutaneous vertebroplasty using hydroxyapatite blocks (VPHA) for osteoporotic vertebral fractures at our institution. Between January 2018 and May 2021, VPHA+PSF treatment was performed in ten cases, and reoperation was performed in four. Eight cases are reported in detail and discussed with additional literature review.</p><p>Case Report: A 78-year-old male was injured in a fall, with a Th12 vertebral fracture. He was referred to our department approximately 3 months after the injury, and VPHA+PSF was performed at 3 above 2 below approximately 4 months after the injury. Preoperative lumbar spine bone mineral density was 64.4% young adult mean. The local kyphosis angle was −34° preoperatively but improved to −2°postoperatively. Symptoms of lower limb paralysis gradually improved, and he was able to walk with a walker. However, 1 month postoperatively, lateral X-ray of the lumbar spine showed the L1 vertebral fracture and lower screw backout, and the local kyphosis angle worsened to −22°. There was no worsening of paralysis of the lower limbs, but he had severe back pain and difficulty in walking; thus, reoperation was performed 2 months after primary surgery. After reoperation, his back pain improved, and he is now able to walk unassisted 1 year after the second surgery.</p><p>Conclusions: Although vertebral body-height reconstruction by VPHA is easy to perform, the power of the anterior column support can be weak. In cases in which the correction angle is large, reoperation may be required because fixation force cannot be maintained until the column is stabilized. We believe that it is necessary to avoid revision surgery after VPHA. Therefore, we must consider using augmentation techniques, such as sublaminar wiring or hooks, and another screw insertion method.</p>