Evidence map›Paper›PMID 42644196›Full record

ArticleJournal of craniovertebral junction & spine

Biomechanical comparison of seven occipital-cervical fixation constructs using finite element modeling.

Ian Polyzois, Jaskaran Singh, Sara Gustafson, Trevor Gascoyne, Franck Le Navéaux, Pierre Legay, Michael Goytan

Abstract read
In one paragraph

Article in Journal of craniovertebral junction & spine. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors.

Ian PolyzoisOrthopaedic Innovation Centre, Winnipeg, MB, Canada.
Jaskaran SinghMax Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada.
Sara GustafsonOrthopaedic Innovation Centre, Winnipeg, MB, Canada.
Trevor GascoyneOrthopaedic Innovation Centre, Winnipeg, MB, Canada.
Franck Le NavéauxNumalogics, Montreal, QC, Canada.
Pierre LegayNumalogics, Montreal, QC, Canada.
Michael GoytanMax Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Study Design: This was a basic science study. Objective: The objective of this study was to determine which occipital-cervical (OC) fixation construct best balances construct stiffness with minimization of occipital screw pullout forces. Materials and Methods: Finite element analysis was used to simulate seven OC construct variations spanning across C1 with fixation in C2 and C3. Variations included the use of occiput rods, keel plates with varying width, two-hole clamps, two-hole clamps in addition to medial or lateral one-hole clamps, and occiput screw diameter. Modeling was in accordance with ASTM F2706/ISO 12189 guidelines. Materials were in accordance with ASTM F1295/ASTM F1839/ISO 10243 guidelines. Outcomes included bending stiffness, axial screw pullout reaction forces, and von Mises stress distribution to identify stress localization and predicted failure modes. Constructs were ranked using multiattribute utility theory (MAUT). Results: Construct E (comprised two-hole clamps with added one-hole medial clamps) demonstrated the highest bending stiffness (820 N.mm/deg) and the highest MAUT utility score (0.79), representing the optimal balance of stiffness and minimized screw pullout forces. Construct F (comprised two-hole clamps alone) demonstrated the lowest bending stiffness (509 N.mm/deg). Conclusions: A construct composed of medially fixed one-hole and two-hole clamps provided the best balance of bending stiffness and minimized occipital screw pullout reaction forces. Aligning screws near the median plane, using bilateral clamp fixation, and avoiding components that mechanically join the two rods improved construct performance. Increasing occipital screw diameter from 4.5 mm to 5.0 mm had little biomechanical impact. Stress localization at occipital component-rod interfaces suggests a potential weak point with risk of notching and fatigue failure.

Indexed as

Biomechanicalcervicalcraniovertebraloccipitocervicalocciputspinestiffness

Identifiers

PMID42644196
PMCPMC13506116

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.