A radio-anatomical study of median arcuate ligament syndrome: unveiling the morphology and morphometry of median arcuate ligament, celiac trunk, and superior mesenteric artery.

Purpose: In the context of medical literature, a significant lacuna exists in understanding median arcuate ligament syndrome (MALS). While clinical aspects are well documented, literature lacks a robust exploration of the anatomical relationship between the celiac trunk and the median arcuate ligament (MAL).

Methods: Morphometric parameters, including the vertebral level of MAL origin, MAL thickness, celiac trunk (CeT) origin level, diameter, and distances between CeT/Superior Mesenteric Artery (SMA) and the MAL center were observed on 250 CT angiograms. Cadavers (n = 11) were dissected to examine the same parameters and histo-morphological examination of MAL tissue was done.

Results: Radiological findings established average MAL thickness of 7.79 ± 2.58 mm. The celiac trunk typically originated at T12. The average distance between the celiac trunk and the MAL center was 1.32 ± 2.04 mm. The angle of the celiac trunk to the abdominal aorta was primarily obtuse. The average celiac trunk diameter was 5.53 ± 1.33 mm. Histological examinations revealed a diverse MAL composition, indicating variable mechanical properties.

Conclusion: This study provides comprehensive morphometric data on the anatomical relationship between the MAL and the celiac trunk. In contrast to available literature which says the average MAL thickness of > 4 mm is an indicator of increased thickness, we observed much higher average thickness in the studied population. The findings contribute to a better understanding of normal anatomical variations which can serve as reference values for accurate radiological diagnosis of MALS. The histological examination revealed the heterogeneous nature of the MAL tissue composition, suggesting variable mechanical properties and functions in different regions.