Innervation of the Psoas Major The psoas major muscle is innervated by the anterior rami of the lumbar spinal nerves L1, L2, and L3. Nerve Supply Source: ▪️The anterior rami of L1, L2, and L3 lumbar spinal nerves arise from the lumbar plexus, which is embedded within the psoas major muscle itself. Pathway: ▪️The anterior rami emerge from the intervertebral foramina and travel through the psoas major muscle. ▪️Branches provide motor innervation to the psoas major. Functional Contribution Primary

Anatomy of the psoas The psoas muscle is a long, ribbon-shaped muscle that starts at your lower back, and runs down through your pelvis where it joins the iliacus and connects to the top of your thigh bone (lesser trochanters). You can’t talk or work on the psoas muscle without also mentioning the iliacus. Together, these muscles are known as the iliopsoas muscle and they form the strongest of the hip flexor muscles while also supporting your spine. #anatomy | YOGABODY