What is the primary function of the psoas major muscle?

The primary function of the psoas major muscle is the flexion of the hip. This deep muscle originates from the lumbar vertebrae and inserts into the lesser trochanter of the femur, enabling it to effectively facilitate hip flexion. When the psoas major contracts, it brings the thigh closer to the torso, which is a crucial movement in activities such as walking, running, and climbing.

The psoas major also plays a role in maintaining proper posture and stabilizing the spine, but its most notable and primary function is indeed hip flexion. Understanding the specific function of this muscle is fundamental for massage therapists, as the psoas can become tight or dysfunctional due to prolonged sitting or poor posture, leading to lower back pain and other musculoskeletal issues.