Psoas minor is one of the muscles of the posterior abdominal wall. It is absent in 30-40% of the population.

It originates from the:

• vertebral bodies of T12 and L1
• intervertebral disc between T12 and L1

Passing inferiorly and slightly laterally with a long tendon, it inserts into the:

• fascia overlying the iliopsoas muscle
• pectineal line of the pubis
• iliopubic eminence

It is innervated by the anterior primary rami of the first lumbar nerve (L1).

Psoas minor has a weak action to:

• flex the pelvis
• flex the lumbar region of the vertebral column