Background: The pullout strength of pedicle screws is influenced by many factors, including diameter of the screws, implant design, and augmentation with bone cement such as PMMA. In the present study, the pullout strength of an innovative fenestrated screw augmented with PMMA was investigated and was compared to unaugmented fenestrated, standard and dual outer diameter screw.
Methods: Twenty four thoracolumbar vertebrae (T10-L5, age 60 to 70 years) from three cadavers were implanted with the four different pedicle screws. Twelve screws of each type were instrumented into either left or right pedicle with standard screw paired with unaugmented and dual outer diameter screw paired with augmented fenestrated screw in any given vertebra. Axial pullout testing was conducted at a rate of 5 mm/min. Force to failure (Newtons) for each pedicle screw was recorded.
Results: The augmented fenestrated screws had the highest pullout strength, which represented an average increase of 149%, 141%, and 78% in comparison to unaugmented, standard, and dual outer diameter screws, respectively. Pullout strength of unaugmented screws was comparable to that of standard screws, however it was significantly lower than dual outer diameter screws.
Conclusions: Fenestrated screws augmented with PMMA improve the fixation strength and result in significantly higher pullout strength compared to dual outer diameter, standard and unaugmented fenestrated screws. Screws with dual outer diameter provided enhanced bone-screw purchase and may be considered as an alternative technique to increase the bone-screw interface in cases where augmentation using bone cement is not feasible. Unaugmented screws can be left in the pedicle even without cement and provide similar pullout strength to standard screws.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4422437 | PMC |
| http://dx.doi.org/10.1186/s13013-015-0039-6 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Effect of Plasma Treatment on Coating Adhesion and Tensile Strength in Uncoated and Coated Rubber Under Aging.
Materials (Basel)
January 2025
Mechanical Engineering Department, Universidad Carlos III de Madrid, 28911 Leganés, Spain.
The degradation of rubber materials under environmental and mechanical stress presents a significant challenge, particularly due to UV (ultraviolet light) exposure, which severely impacts the material's physical properties. This study aims to enhance the UV stability and longevity of rubber by evaluating the performance of modified polyurethane and silicone coatings as protective stabilizers. Natural rubber-styrene-butadiene rubber (NR-SBR), known for its exceptional mechanical properties, was selected as the base material.
View Article and Find Full Text PDFA Study on the Impact of Temperature on the Anchoring Durability of Carbon-Fiber-Reinforced Polymer Cables.
Materials (Basel)
January 2025
School of Civil & Environmental Engineering and Geography Science, Ningbo University, Ningbo 315211, China.
To improve the application of carbon-fiber-reinforced polymers (CFRPs) in civil engineering, the long-term durability of CFRP anchorage systems has become a critical issue. Temperature fluctuations can significantly impact the bond performance between CFRPs and the load transfer medium (LTM), making it essential to understand the effects of temperature on the durability of CFRP anchorages. Therefore, this study investigates the influence of temperature on the durability of CFRP anchorages through aging tests on 30 epoxy-filled CFRP-bonded anchorage specimens, followed by pull-out tests.
View Article and Find Full Text PDFPurpose: This study aimed to compare the biomechanical properties of four meniscal suture configurations-two simple sutures (TSS), two cinch sutures, a locking loop stitch (LLS), and a delta-grip stitch (DGS)-for transtibial pullout repair of medial meniscus posterior root tears (MMPRTs) using porcine menisci.
Methods: Forty porcine menisci were randomly assigned to each suture configuration with all-inside repair. All specimens were subjected to cyclic loading for 1000 cycles, followed by a load-to-failure test.
Suture Anchor Fixation of the Pediatric Posteromedial and Posterolateral Menisco-Tibial Ligament Complex Matches or Exceeds Native Tissue Strength: A Cadaveric Study.
J ISAKOS
January 2025
Department of Orthopaedic Surgery, Stanford University, Stanford, California, USA. Electronic address:
Objectives: To compare the biomechanical strength and stiffness of the native posteromedial and posterolateral meniscotibial ligament complex (MTLC) to suture anchor repair of the MTLC.
Methods: Biomechanical testing was performed on 24 fresh-frozen pediatric human knees. Four conditions were tested: native posteromedial MTLC (n=14), native posterolateral MTLC (n=14), posteromedial MTLC repair (n=5), and posterolateral MTLC repair (n=5).
Investigation of Chloride Salt Erosion on Asphalt Binders and Mixtures: Performance Evaluation and Correlation Analysis.
Materials (Basel)
January 2025
College of Engineering, Zhejiang Normal University, Jinhua 321004, China.
Asphalt pavement, widely utilized in transportation infrastructure due to its favourable properties, faces significant degradation from chloride salt erosion in coastal areas and winter deicing regions. In this study, two commonly used asphalt binders, 70# base asphalt and SBS (Styrene-Butadiene-Styrene)-modified asphalt, were utilized to study the chloride salt erosion effect on asphalt pavement by immersing materials in laboratory-prepared chloride salt solutions. The conventional properties and adhesion of asphalt were assessed using penetration, softening point, ductility, and pull-off tests, while Fourier transform infrared spectroscopy (FTIR) elucidated the erosion mechanism.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!