Mechanical function of the annulus fibrosus is preserved following quasi-static compression resulting in endplate fracture
Bibliographic record
Abstract
Background Vertebral fractures in young populations are associated with intervertebral disc disorders later in life. However, damage to the annulus fibrosus has been observed in rapidly loaded spines even without the subsequent occurrence of a fracture. Therefore, it may not be the fracture event that compromises the disc, but rather the manner in which the disc is loaded. The purpose of this study was to quantify the mechanical properties of the annulus fibrosus following quasi-static compressive loading of the motion segment either to sub-fracture or fracture-inducing magnitude. Methods Porcine cervical motion segments were axial compressed at 0.1 mm/s, either until endplate fracture occurred (‘fracture group'), or until segments reached 75 % of average fracture stress as determined from the fracture group (‘sub-fracture group'). An unloaded control group was also included. Post-loading, three samples of the annulus were excised. The first was mounted in a 180 o peel test configuration in order to quantify lamellar adhesion. The other two samples were excised from the superficial and midspan region of the annulus and were exposed to uniaxial tension to 50 % strain. Findings Lamellar adhesion and tensile annulus mechanics did not differ between the fracture and sub-fracture group, nor between the unloaded controls. Interpretation Given the lack of differences in annular mechanical properties across the three conditions, it was concluded that under very slow, quasi-static compressive loading conditions, the annulus appeared undamaged even in the group that sustained a fracture; this is likely because a significant viscoelastic response was not generated in the disc under these slow loading conditions.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".