Rectus Femoris Muscle

Origin

The rectus femoris muscle originates from the ilium via two tendons:

- a straight tendon, which attaches to the anterior inferior iliac spine;

- a reflected tendon, which attaches to the supraacetabular groove of ilium.

These two tendons travel inferiorly and converge to a single tendon, which becomes continuous with the muscle belly of the rectus femoris muscle.

Insertion

The fibers of the rectus femoris muscle travel inferiorly and converge with the fibers of the vastus medialis, intermedius and lateralis muscles to form the tendon of quadriceps femoris muscle. The fibers of this tendon travel superficial to the patella, where they become continuous with the patellar ligament, which inserts onto the tibial tuberosity.

Key Features & Anatomical Relations

The rectus femoris muscle is one of the four muscles that form the quadriceps femoris muscle, the other three being the vastus medialis, intermedius and lateralis muscles. It is a long, thick, bipennate type of skeletal muscle.

It is located:

- anterior (superficial) to the iliofemoral ligament and the vastus intermedius muscle;

- posterior (deep) to the sartorius muscle (at its proximal end);

- medial to the tensor fasciae latae and vastus lateralis muscles;

- lateral to the vastus medialis muscle.

Actions & Testing

The rectus femoris muscle is involved in multiple actions:

- It extends the leg at the knee joint, via the tendon of quadriceps femoris muscle and patellar ligament;

- It assists in flexion of the thigh at the hip joint.

The rectus femoris muscle cannot be tested in isolation, therefore all four muscles of the quadriceps femoris are tested simultaneously by extending the leg at the knee joint against resistance while lying in the supine position with the hip flexed, during which the rectus femoris muscle can be palpated (Standring, 2016).

List of Clinical Correlates

- Patellar instability

- Patellar pain

References

Standring, S. (2016) Gray's Anatomy: The Anatomical Basis of Clinical Practice. Gray's Anatomy Series 41st edn.: Elsevier Limited.