Evidence map›Paper›PMID 34561728›Full record

ArticleEuropean spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society2021

Radial trend in murine annulus fibrosus fiber orientation is best explained by vertebral growth.

Ali Raza, Arthur J Michalek

Abstract read
PubMed Publisher
In one paragraph

Article in European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

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

4 citing papers in PubMed.

  1. Review
  2. Article
  3. Article
  4. Review
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

2 authors.

Ali RazaDepartment of Mechanical and Aeronautical Engineering, Clarkson University, Box 5725, Potsdam, NY, 13699, USA.ORCID 0000-0002-1544-8102
Arthur J MichalekDepartment of Mechanical and Aeronautical Engineering, Clarkson University, Box 5725, Potsdam, NY, 13699, USA. ajmichal@clarkson.edu.ORCID 0000-0001-9417-9344

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeThe intervertebral disc (IVD) annulus fibrosus (AF) is composed of concentric lamellae with alternating right- and left-handed helically oriented collagen fiber bundles. This arrangement results in anisotropic material properties, which depend on local fiber orientations. Prior measurements of fiber inclination angles in human lumbar and bovine caudal IVDs found a significantly higher inclination angle in the inner AF than outer, though it is currently unknown if this pattern is conserved in smaller mammalian species. Additionally, the physical mechanism behind this pattern remains un-determined.

methodsIn this study, AF fiber angles were measured histologically in murine caudal IVDs and compared to previously published values from bovine caudal IVDs. Fiber angles were also predicted using three theoretical models, including two based on adaptation to internal swelling pressure and one based on vertebral body growth.

resultsFiber angle was found to significantly decrease from 49.5 ± 3.8° in the inner AF to 34.5 ± 6.6° in the outer AF. While steeper than in bovine discs at all locations, the trend with radial position was comparable between species. This trend was best fit by growth-based model and opposite of that predicted by the pressure vessel models.

conclusionTrends in AF fiber orientation are conserved between mammalian species. Modeling results suggest that the AF tissue microstructure is more likely to be driven by adjacent vertebral body growth than adapted for optimal mechanical performance.

Indexed as

Annulus FibrosusIntervertebral DiscAnimalsAnisotropyCattleHumansLumbosacral RegionMiceDevelopmentalMurine caudalPolarized light microscopyTissue microstructure

Identifiers

PMID34561728

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

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.