STUDY DESIGN: Biomechanical study using human thoracolumbar spines. OBJECTIVE: To assess the strength of fixation of pedicle screws augmented with Nesplon tape applied sublaminar or applied subpars. SUMMARY OF BACKGROUND DATA: There are no reports on the biomechanical assessment of Nesplon tape used for pedicle screw augmentation. METHODS: Experiment 1: pedicle screws were inserted into bilateral pedicles as follows: (1) pedicle screw alone connected to a rod (PS alone), (2) pedicle screw augmented with Nesplon tape applied sublaminar, connected to a rod [pedicle screw applied sublaminar (PSSL)], and (3) pedicle screw augmented with tape applied subpars, connected to a rod [pedicle screw applied subpars (PSSP)]. The rods were pulled and pushed until the pedicle screw was loose. Experiment 2: 6 thoracolumbar spines were biomechanically tested as follows: axial compression, flexion, extension, left and right lateral bending, and left and right axial rotation. This sequence was applied to: (1) the intact spine; (2) the spine made unstable; (3) the spine fixed by pedicle screws and rods (PS alone); (4) the same as 3, but with the pedicle screws augmented using Nesplon tape applied sublaminar (PSSL); and (5) the same as 3, but with pedicle screws augmented using tape applied subpars (PSSP). From the load-deformation curves, stiffness values were calculated. RESULTS: Experiment 1: the pedicle screws augmented by sublaminar or subpars tape (PSSL or PSSP) showed significantly greater fixation strength compared with those pedicles that were not augmented by tape (PS alone). Experiment 2: a pedicle screw/rod construct augmented by tape provided a stiffer construct than the same construct without augmentation. CONCLUSIONS: Pedicle screws that are inserted into the osteoporotic thoracolumbar spine and augmented by Nesplon tape applied sublaminar or subpars provide firmer fixation of the screws and a stiffer pedicle screw/rod construct than the same construct without augmentation by tape.
STUDY DESIGN: Biomechanical study using human thoracolumbar spines. OBJECTIVE: To assess the strength of fixation of pedicle screws augmented with Nesplon tape applied sublaminar or applied subpars. SUMMARY OF BACKGROUND DATA: There are no reports on the biomechanical assessment of Nesplon tape used for pedicle screw augmentation. METHODS: Experiment 1: pedicle screws were inserted into bilateral pedicles as follows: (1) pedicle screw alone connected to a rod (PS alone), (2) pedicle screw augmented with Nesplon tape applied sublaminar, connected to a rod [pedicle screw applied sublaminar (PSSL)], and (3) pedicle screw augmented with tape applied subpars, connected to a rod [pedicle screw applied subpars (PSSP)]. The rods were pulled and pushed until the pedicle screw was loose. Experiment 2: 6 thoracolumbar spines were biomechanically tested as follows: axial compression, flexion, extension, left and right lateral bending, and left and right axial rotation. This sequence was applied to: (1) the intact spine; (2) the spine made unstable; (3) the spine fixed by pedicle screws and rods (PS alone); (4) the same as 3, but with the pedicle screws augmented using Nesplon tape applied sublaminar (PSSL); and (5) the same as 3, but with pedicle screws augmented using tape applied subpars (PSSP). From the load-deformation curves, stiffness values were calculated. RESULTS: Experiment 1: the pedicle screws augmented by sublaminar or subpars tape (PSSL or PSSP) showed significantly greater fixation strength compared with those pedicles that were not augmented by tape (PS alone). Experiment 2: a pedicle screw/rod construct augmented by tape provided a stiffer construct than the same construct without augmentation. CONCLUSIONS: Pedicle screws that are inserted into the osteoporotic thoracolumbar spine and augmented by Nesplon tape applied sublaminar or subpars provide firmer fixation of the screws and a stiffer pedicle screw/rod construct than the same construct without augmentation by tape.