The pectineus is a flat, quadrangular muscle located in the upper inner thigh. It plays a key role in hip movement, primarily assisting with hip flexion and adduction. The muscle originates from the pectineal line of the pubis and inserts into the femur, making it important for activities like walking and running. This muscle is innervated by the femoral nerve and sometimes receives additional innervation from the obturator nerve. Due to its position, the pectineus is also involved in stabilizing the pelvis during movement. Strengthening this muscle can enhance overall leg function and athletic performance.