Increasing pedicle screw anchoring in the osteoporotic spine by cement injection through the implant

Abstract

Instrumented spinal fusion in patients with osteoporosis is challenging because of the poor bone quality and is complicated by an elevated risk of delayed hardware failure. The author treated two patients presenting with severe osteoporosis, spinal stenosis, and degenerative spondylolisthesis. He performed decompressive laminectomy, posterolateral fusion, and pedicle screw (PS) fixation involving screws with side openings that allow cement to be injected through the implant. The cement injection was conducted under fluoroscopic control without complications. Although this technique needs validation in a larger population of patients, the author believes that the injection of cement through these PSs can be performed safely in carefully selected patients. This technique creates not only a vertebroplasty-like effect that strengthens the vertebral body but also provides the additional stability afforded by the immediate anchoring of the screw, which may allow a shorter-length construct, save mobile segments, and finally reduce the risk of hardware failure.