Abstract
Background and aim
The cardio-oesophageal sphincter that is located in close longitudinal proximity to the origin of the lesser curvature of the stomach has a unique pattern of external muscle fibres whose inner oblique layer would normally form an elongated sling and the middle partially circular layer would form a projecting clasp into the already existing muscular sling of the former congruently, which would result in the formation of an anatomical sphincter in that area that would normally be devoid of the external longitudinal muscle layer coat. Certain authors have disagreed with the notion of this standard literature and have proposed that the clasp and sling fibres need not necessarily be congruent and may even remain independent of each other with partial contributions from the longitudinal muscle layers as well that may arise tangentially in different populations, which may in turn contribute to reflux oesophagitis in that population. Hence, the clasp and sling fibre muscular patterns were observed in six formalin-embalmed cadavers at the department of anatomy in a tertiary care institute as part of routine dissections in series, and the findings were then reported.
Findings
At the junction of the lesser curvature of the stomach with the oesophagus, all six cadavers showed a longitudinal sling pattern as opposed to the conventional oblique sling. The circular muscle layer was found to be merged with the outer longitudinal muscle layer to form the sling that pulled away from the clasp, resulting in a loss of congruency for the same. The clasp fibres, however, were found to be contributed by the inner oblique muscle layer. The conventional perpendicular or tangential merging of the clasp with the sling was not observed; instead, an obtuse, blunt angular merging of the clasp with the sling was observed.
Discussion
The deviation of the sling from the clasp could indicate a lack of a proper fit between them at the cardio-oesophageal sphincter. The lack of robustness in the attachment of the clasp to the sling may possibly contribute to the diminished taut pull of the clasp in this subset of the population. These would be significant determinants for a predisposition to reflux oesophagitis and Barrett’s oesophagus.
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Data availability
The materials that were used by the researchers to embalm the cadavers as well as to dissect the cadavers were already in use before the start of this study and had been purchased earlier by the establishment section of the institute prior to the start of this research and they were not procured as a result of funding/grants and neither did the researchers of this study apply for any grants nor did they receive any monetary support to purchase the materials related to this study. The data pertaining to the profile of the deceased persons who had donated their bodies for dissection were to be kept confidential within the records of the institute as per the mandate issued by the ethics board.
Abbreviations
- CES:
-
Cardio-oesophageal sphincter
- Cm:
-
Centimetre
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Acknowledgements
The authors of this research study would like to thank the Ethics Committee cum research wing of the tertiary care institute where the researchers are employed for having permitted them to conduct this study. The authors would also like to acknowledge the deceased who had donated their bodies for the purpose of scientific dissections as well as to their relatives who had consented to this involved donation, thereby helping the researchers in their study. The authors would also like to thank Dr Ram Reddy, gastroenterologist, global hospital, Hyderabad, India, for providing valuable insights into the understanding of the cardio-oesophageal sphincter but was not related to this research per se.
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The authors would like to declare that they have not received any intramural or extramural financial support/grants/funds for this study.
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MC: planning, implementation and supervision of research. SS: execution of research work, data collection, analysis and interpretation of results.
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The authors would like to declare that they have no competing interest with other researchers to the best of their knowledge as far as this study is concerned.
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The authors would like to affirm that they have obtained a proper ethics approval from the institutional research committee cum ethics review board for this study. The ethics approval for this study was obtained only after an internal review meeting held within the department of the researchers followed by an external review meeting held by representatives outside the department and institution where the researchers work. The allotted ethics approval number for this study was AIIMS/BBN/IEC/MAR/2023/273. The cadavers that were procured for this study were obtained either as a result of willful donation of bodies of the deceased through their self-attested will prior to their death or through a proper informed written consent from the relatives of the deceased in accordance with the guidelines that were laid down by the ethics board, wherein the consent to publish the findings related to dissection of cadavers was also obtained.
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Chandrupatla, M., Susai, S. A study on the congruence and proximity of the sling and clasp fibres at the cardio-esophageal junction of the stomach. Surg Radiol Anat 45, 1477–1482 (2023). https://doi.org/10.1007/s00276-023-03243-3
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DOI: https://doi.org/10.1007/s00276-023-03243-3