The median sacral artery in rectal blood supply: A cadaveric study
Bibliographic record
Abstract
INTRODUCTION: Insufficient blood supply to the posterior rectal remnant after proctectomy is a possible mechanism for anastomotic leakage. The median sacral artery (MSA) is not generally considered to participate in the rectal blood supply, although some case studies have reported the rectum being supplied by it. The aim of this study is to elucidate the anatomy of the MSA in relation to the posterior rectal wall. METHODS: Nineteen embalmed cadavers (12 males, seven females; mean age: 76 ± 9 years) were injected with a colored radio-opaque mixture in the aortic bifurcation, radiographed and subsequently dissected along the sacrum. The relationship between the MSA and the rectum was observed and the diameter of the MSA was measured 2 cm below the aortic bifurcation. RESULTS: MSAs were identified in 16 (84.2%) of the 19 cadavers. Nine MSAs (47.4%) reached the rectal wall and penetrated it. MSAs that reached the posterior rectum took two different routes in the presacral space. Dissection and radiography showed four penetrating MSAs (21.1%) ending in a branching pattern and five (26.3%) as a tapering vessel. Seven MSAs (36.8%) did not reach the rectal wall. The mean MSA diameter was 1.98 ± 0.12 mm. CONCLUSIONS: Almost half the MSAs reached and penetrated the posterior rectal wall, suggesting possible participation in the rectal blood supply. A large portion of the MSAs that penetrate the rectal wall run outside surgical margins and could continue to provide blood supply to the rectal remnant, potentially preventing anastomotic leakage.
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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.004 | 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".