While “tenderloin” refers to a cut of meat, humans possess a homologous muscle with anatomical similarities that plays an important role in movement. This muscle, not given a culinary name in human anatomy, is deeply situated and contributes substantially to our mobility and posture.
What is a Tenderloin?
In the culinary world, “tenderloin” refers to a specific cut of meat, from beef, pork, or lamb, known for its exceptional tenderness. This muscle is located along the spine, inside the animal’s loin section. For example, beef tenderloin, also known as filet mignon, is a long, narrow muscle running along the cow’s spine, between the sirloin and ribs.
The primary reason for its tenderness is that it is a non-weight-bearing muscle, experiencing minimal use during the animal’s life. Unlike heavily exercised muscles, the tenderloin develops fewer collagen fibers, which are connective tissues that make meat tough. This results in a delicate texture, making it a highly prized and often expensive cut.
The Human Psoas Muscle
The human muscle analogous to the animal tenderloin is the psoas major. Often discussed with the iliacus muscle as the “iliopsoas,” this deep muscle is central to human anatomy.
The psoas major is a long, thick, fusiform muscle located in the lumbar region of the trunk, positioned lateral to the lumbar vertebrae. It runs on either side of the spinal column, extending towards the pelvis.
The psoas major originates from the transverse processes of the lumbar vertebrae and intervening intervertebral discs. Its fibers extend inferolaterally, passing through the lesser pelvis and beneath the inguinal ligament. It then merges with the iliacus muscle, inserting onto the lesser trochanter of the femur, a bony prominence on the upper thigh bone.
This deep, protected location within the body’s core is similar to the tenderloin’s position in animals.
Role and Significance in Human Anatomy
The psoas muscle is a fundamental component of human movement and stability. Its primary function is hip flexion, which involves lifting the knee towards the torso or bending the trunk forward at the hip. This action is essential for everyday activities like walking, running, climbing stairs, and sitting up.
Beyond hip flexion, the psoas also contributes significantly to trunk stabilization and maintaining proper posture. It helps stabilize the vertebral column by maintaining the natural curve in the lower back.
While anatomically similar to an animal tenderloin, the human psoas is not consumed, nor is the culinary term applied. Its continuous engagement in bipedal locomotion and upright posture highlights its importance in human physiology, far beyond any culinary comparison.