Cement-augmented Carbon-Fiber-reinforced pedicle screw instrumentation for spinal metastases: safety and efficacy.

Carbon-fiber-reinforced (CFR) polyetheretherketone (PEEK) combines the high strength of metals with the extensive biocompatibility and imaging compatibility of polymers. CFR PEEK composite is similar to the stiffness of cortical bone (approximately 15–20 GPa) and shows comparable performance to metallic materials such as titanium alloy, cobalt chrome alloy, and stainless steel in terms of strength. CFR-PEEK becomes an attractive alternative to the metallic materials traditionally used in spinal implants (e.g. pedicle screw rod fixation). Finite element (FE) models have been developed to study the biomechanical behaviors of spinal structures with pedicle screw rod fixation ([1–5]). However, it is limited to implement these models to study the bone screw interaction, and local bone strain at the bone screw interface due to the intrinsic low mesh density of the intact model. The aim of this study is to develop a refined block fixation FE model to investigate the load sharing, bone screw interaction, and strain/stress in CFR PEEK construct.

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Pedicle screw anchorage of carbon fiber-reinforced PEEK screws under cyclic loading

European Spine Journal ◽

10.1007/s00586-018-5538-8 ◽

2018 ◽

Vol 27 (8) ◽

pp. 1775-1784 ◽

Cited By ~ 15

Author(s):

Richard A. Lindtner ◽

Rene Schmid ◽

Thomas Nydegger ◽

Marko Konschake ◽

Werner Schmoelz

Keyword(s):

Carbon Fiber ◽

Cyclic Loading ◽

Pedicle Screw ◽

Fiber Reinforced ◽

Carbon Fiber Reinforced

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Carbon-fiber reinforced PEEK instrumentation for spondylodiscitis: a single center experience on safety and efficacy

Scientific Reports ◽

10.1038/s41598-021-81960-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ann-Kathrin Joerger ◽

Ehab Shiban ◽

Sandro M. Krieg ◽

Bernhard Meyer

Keyword(s):

Carbon Fiber ◽

Pedicle Screw ◽

Bacterial Adhesion ◽

Spinal Instrumentation ◽

Screw Loosening ◽

Fiber Reinforced ◽

Single Center ◽

Carbon Fiber Reinforced ◽

Matching Criteria ◽

Pedicle Screw Loosening

AbstractRadiolucent carbon-fiber-reinforced (CFR) polyethyl-ether-ether-ketone (PEEK) has been established in spinal instrumentation for oncological reasons. Laboratory data reported comparable bacterial adhesion as titanium. Thus, using of CFR-PEEK spinal instrumentation for spondylodiscitis bases on artifact-free imaging to evaluate therapeutic success. Studies comparing the rate of pedicle screw loosening and relapse of spondylodiscitis following titanium versus CFR-PEEK instrumentation do not exist so far. This study evaluates the rate of pedicle screw loosening and recurrence of spondylodiscitis after CFR-PEEK instrumentation for spondylodiscitis compared to titanium. We conducted a prospective single center study between June 2018 and March 2019 on consecutive 23 patients with thoracolumbar spondylodiscitis. Imaging data was evaluated for screw loosening at a minimum of three months after surgery. A matched-pair analysis was performed using spondylodiscitis cases between 2014 and 2016 using titanium instrumentation for equal localization, surgery, and microorganism class. Among 17 cases with follow-up imaging, six cases (35%) showed screw loosening while only 14% (two patients) with titanium instrumentation were loosened (p = 0.004). In both groups the most frequent bacterium was Staphylococcus aureus, followed by Staphylococcus epidermidis. From the S. aureus cases, one infection in both groups was caused by methicillin resistant species (MRSA). No difference was found in the rate of 360° fusion in either group due to matching criteria. As opposed to other indications CFR-PEEK screws show more loosening than titanium in this series with two potentially underlying reasons: a probably stronger bacterial adhesion on CFR-PEEK in vivo as shown by a statistical trend in vitro and instrumentation of spondylytic vertebrae. Until these factors are validated, we advise caution when implanting CFR-PEEK screws in infectious cases.

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Effects of high pressure on the crystallization of carbon fiber reinforced polyetheretherketone (CF/PEEK) laminate composites

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100177519 ◽

1990 ◽

Vol 48 (4) ◽

pp. 876-877

Author(s):

Hong-Ming Lin ◽

C. H. Liu ◽

R. F. Lee

Keyword(s):

High Pressure ◽

Carbon Fiber ◽

Sample Surface ◽

High Yield ◽

Fiber Reinforced ◽

Laminate Composites ◽

Peek Composite ◽

Continuous Carbon Fiber ◽

Carbon Fiber Reinforced

Polyetheretherketone (PEEK) is a crystallizable thermoplastic used as composite matrix materials in application which requires high yield stress, high toughness, long term high temperature service, and resistance to solvent and radiation. There have been several reports on the crystallization behavior of neat PEEK and of CF/PEEK composite. Other reports discussed the effects of crystallization on the mechanical properties of PEEK and CF/PEEK composites. However, these reports were all concerned with the crystallization or melting processes at or close to atmospheric pressure. Thus, the effects of high pressure on the crystallization of CF/PEEK will be examined in this study.The continuous carbon fiber reinforced PEEK (CF/PEEK) laminate composite with 68 wt.% of fibers was obtained from Imperial Chemical Industry (ICI). For the high pressure experiments, HIP was used to keep these samples under 1000, 1500 or 2000 atm. Then the samples were slowly cooled from 420 °C to 60 °C in the cooling rate about 1 - 2 degree per minute to induce high pressure crystallization. After the high pressure treatment, the samples were scanned in regular DSC to study the crystallinity and the melting temperature. Following the regular polishing, etching, and gold coating of the sample surface, the scanning electron microscope (SEM) was used to image the microstructure of the crystals. Also the samples about 25mmx5mmx3mm were prepared for the 3-point bending tests.

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