Experimentally Dissociating the Acute Mechanisms of Endplate Fracture Lesions and Schmorl's Node Injuries Using a Porcine Cervical Spine Model
Bibliographic record
Abstract
STUDY DESIGN: This is an in vitro biomechanical study. OBJECTIVE: This study evaluated the influence of localized trabecular bone strength deficits and loading rate as determinants of Schmorl's node and fracture lesion incidence. The failure load (ultimate compression tolerance [UCT]), loading stiffness, and failure morphology were assessed after acute compression loading and failure. SUMMARY OF BACKGROUND DATA: The cartilaginous endplate is vulnerable to injuries such as Schmorl's nodes and fracture lesions. While both injuries are associated with acute compression traumas, the factors that distinguish their incidence are poorly understood. METHODS: Forty-eight porcine spinal units (domestic hog, 5-10 mo, ~110 kg) were assigned to one of eight experimental groups that differed by initial condition (control, sham, experimentally produced chemical fragility, and structural void) and loading rate (3 kN/s, 9kN/s). A servo-hydraulic materials testing system was used to perform acute compression testing until observed failure in the specimen. Post-loading dissection was performed to classify injury morphologies. Between group differences in UCT and loading stiffness were evaluated using a general linear model and injury distributions were evaluated using chi-squared statistics. RESULTS: Schmorl's nodes occurred exclusively in chemical fragility (63%) and structural void groups (37%) and were more prevalent with a 9 kN/s (75%) loading rate compared with 3 kN/s (25%). In contrast, fracture lesions occurred in all FSUs assigned to the control groups (100%) and the majority of those assigned to the sham groups (92%). No between-group differences were observed for UCT and loading stiffness. CONCLUSION: Pre-existing strength deficits of the subchondral trabecular bone can alter endplate injury morphology, particularly when coupled with high loading rates, but the localized strength deficits that were associated with Schmorl's nodes did not appreciably influence measured joint properties.
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) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.003 | 0.001 |
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".