Right medial arcuate ligament

The right medial arcuate ligament (medial lumbocostal arch; medial Haller's arch; internal arcuate ligament) is a tendinous arch in the fascia covering the upper part of the Psoas major; medially, it is continuous with the lateral tendinous margin of the right crus of diaphragm, and is attached to the side of the body of the first or second lumbar vertebra; laterally, it is fixed to the front of the transverse process of the first and, sometimes also, to that of the second lumbar vertebra.

The medial arcuate ligament is distinct from the median arcuate ligament, which is a fibrous band that connects the crura of the diaphragm and can compress the celiac artery, leading to median arcuate ligament syndrome