Biomechanical comparison of pedicle screw augmented with different volumes of polymethylmethacrylate in osteoporotic and severely osteoporotic cadaveric lumbar vertebrae: an experimental study

Abstract Background Context Polymethylmethacrylate (PMMA) is widely used for pedicle screw augmentation in osteoporosis. Intriguingly, there have been no biomechanical comparisons of the stability of pedicle screws augmented with different volumes of PMMA or studies of the relationship between screw...

Full description

Saved in:
Bibliographic Details
Published in:The spine journal 2016-09, Vol.16 (9), p.1124-1132
Main Authors: Liu, Da, MD, PhD, Zhang, Bo, PhD, Xie, Qing-yun, PhD, Kang, Xia, PhD, Zhou, Jiang-jun, PhD, Wang, Cai-ru, MD, PhD, Lei, Wei, MD, PhD, Zheng, Wei, MD, PhD
Format: Article
Language:English
Subjects:
Bone Cements - adverse effects
Bone Cements - therapeutic use
Cadaver
Energy absorbed to failure
Female
Humans
Lumbar Vertebrae - surgery
Maximum axial pullout strength
Neurosurgical Procedures - methods
Orthopedics
Osteoporosis
Osteoporosis - surgery
Pedicle screw
Pedicle Screws - adverse effects
Polymethyl Methacrylate - adverse effects
Polymethyl Methacrylate - therapeutic use
Polymethylmethacrylate
Stiffness
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Abstract Background Context Polymethylmethacrylate (PMMA) is widely used for pedicle screw augmentation in osteoporosis. Intriguingly, there have been no biomechanical comparisons of the stability of pedicle screws augmented with different volumes of PMMA or studies of the relationship between screw stability and volume of PMMA, especially in different degrees of osteoporosis. Purpose The purposes of the study reported here were to compare screw stability by different volumes of PMMA augmentation, to analyze the relationship between screw stability and PMMA volume, and to make a preliminary determination of the optimum volume of PMMA augmentation for different degrees of osteoporosis. Study Design This study is a biomechanical comparison of pedicle screws augmented with various volumes of PMMA in cadaveric lumbar vertebrae. Methods Thirty-six pedicles from 18 osteoporotic lumbar vertebrae were randomly divided into groups A0 through A5, and 36 pedicles from 18 severely osteoporotic lumbar vertebrae were randomly divided into groups B0 through B5. A different volume of PMMA was injected into each one of groups A0 through A5 (0, 0.5, 1.0, 1.5, 2.0, and 2.5 mL, respectively) and into each one of groups B0 through B5 (0, 1.0, 1.5, 2.0, 2.5, and 3.0 mL, respectively), and then pedicle screws were inserted in all vertebrae. After complete solidification of the PMMA, we examined pedicle X-rays, performed axial pullout tests, and determined the maximum axial pullout strength (Fmax ) for all samples. Results No PMMA was found around the screws in groups A0 and B0. In groups A1 to A5 and B1 to B5, screws were wrapped by gradually increasing amounts of PMMA. There was no PMMA leakage or screw malpositioning in any samples. The Fmax in groups A1 through A5 increased by 32.40%, 64.42%, 116.02%, 174.07%, and 207.42%, respectively, compared with that in group A0. There were no significant differences in Fmax between groups A0 and A1, A1 and A2, A2 and A3, A3 and A4, and A4 and A5 (p>.05), but there were significant differences in Fmax between any other two groups (p.05), but there were significant differences in Fmax between any other two groups (p
ISSN:1529-9430
1878-1632
DOI:10.1016/j.spinee.2016.04.015