Polymethylmethacrylate augmentation of conventional pedicle screws in spine surgery - A modified classical method.

Abstract

Background: Pedicle screw augmentation with polymethylmethacrylate (PMMA) is a technique used to reduce the risk of pedicle screw pullout, loss of screw fixation, and implant failure in patients at high risk of mechanical complications.

Study design: This was a retrospective observational study.

Objective: The objective of this study was to describe a modification of the classic augmentation technique of conventional pedicular screw instrumentation in spinal surgery.

Methods: A retrospective analysis was performed on 47 patients over the age of 65 years who underwent spinal surgery using the proposed cement augmentation technique and were followed for 2 years. High-viscosity cement was injected into tapped vertebral pedicles, followed by the insertion of traditional pedicle screws. Patient selection was based on detailed preoperative clinical and imaging evaluations. Outcomes measured included the rate of complications, particularly cement leakage (CL), and the occurrence of neurological or vascular deficits.

Results: A total of 47 patients were treated with 700 conventional screws. A total of 26/700 screws (3.71%) showed CL. According to the modified Yeom classification for CL, 9/700 (0.71%) were type S, 9/700 (0.71%) were type B, and 8/700 (0.57%) were type I; there were no neurological or vascular complications. There were no mechanical complications at 2 years.

Conclusions: This modified augmentation technique for conventional pedicle screws is an alternative for spinal instrumentation in elderly patients with a low incidence of clinically significant complications and also reduces procedure time by facilitating pedicle screw placement.