The Psoas Minor is a thin paired muscle of the posterior abdominopelvic region, placed in front of the Psoas major.The psoas minor muscle is considered inconstant and is often absent, only being present in about 40% of human specimens studied.The psoas minor muscle originates from the vertical fascicles inserted on the last thoracic and first lumbar vertebrae. From there, it passes down onto the medial border of the psoas major and is inserted to the innominate line and the iliopectineal eminence. Additionally, it attaches to and stretches the deep surface of the iliac fascia and occasionally its lowermost fibers reach the inguinal ligament.