RectusMuskeln

Rectusmuskeln refers to a group of straight muscles whose fibers run along a direct line from origin to insertion. In humans the most prominent examples are the rectus abdominis in the anterior abdominal wall and the rectus femoris, one of the quadriceps muscles in the thigh. The term is also used for similar straight muscles in other regions or species.

Rectus abdominis is a long, strap-like muscle along the front of the abdomen. It extends from the pubic crest and pubic symphysis to the xiphoid process and the costal cartilages of ribs 5–7. It is segmented by tendinous intersections and enclosed within the rectus sheath, formed by the aponeuroses of the lateral abdominal muscles. It is innervated primarily by the lower thoracoabdominal nerves (T7–T12) and the subcostal nerve, with blood supply from the superior and inferior epigastric arteries. Functionally, the rectus abdominis flexes the vertebral column, supports abdominal viscera, maintains posture, and aids in forced expiration.

Rectus femoris runs down the front of the thigh as part of the quadriceps. It originates from the anterior inferior iliac spine and part of the hip capsule, and inserts into the quadriceps tendon and the patellar ligament to the tibial tuberosity. It crosses both hip and knee joints, enabling hip flexion and knee extension. It is innervated by the femoral nerve (L2–L4) and supplied by branches of the femoral artery.

Clinically, rectus muscles are considered in abdominal wall and knee–hip movements, and injuries or diastasis can occur in these regions.