Medial arcuate ligament

The diaphragm. Under surface. (Medial arcuate ligament not labeled, but region is visible.)

The Medial Arcuate Ligament is a thickened band of fascia that arches over the Psoas Major and Quadratus Lumborum muscles in the human body. It is one of the three ligaments that make up the posterior abdominal wall, the other two being the Lateral Arcuate Ligament and the Median Arcuate Ligament.

Anatomy

The Medial Arcuate Ligament is a fibrous arch that forms the superior border of the psoas major and quadratus lumborum muscles. It originates from the side of the first or second lumbar vertebra, and inserts into the tip of the twelfth rib. The ligament is covered by the Psoas Fascia, which is a thick sheet of connective tissue that encloses the psoas major and quadratus lumborum muscles.

Function

The primary function of the Medial Arcuate Ligament is to provide a point of attachment for the diaphragm, which is the primary muscle involved in breathing. By anchoring the diaphragm, the ligament helps to maintain the position of this muscle during the process of respiration.

Clinical Significance

In rare cases, the Medial Arcuate Ligament can become thickened and compress the Celiac Artery, leading to a condition known as Median Arcuate Ligament Syndrome (MALS). This can cause symptoms such as abdominal pain, weight loss, and nausea.

See Also

• Diaphragm
• Lateral Arcuate Ligament
• Median Arcuate Ligament