Adductor Magnus

Origin

The adductor magnus muscle consists of two portions:

- the adductor portion, which originates from the inferior pubic ramus and the ramus of ischium;

- the hamstring portion, which originates from the ischial tuberosity.

Insertion

The muscle bellies of the adductor and hamstring portions of the adductor magnus travel inferolaterally, where:

- the adductor portion inserts, via a broad aponeurosis, onto the gluteal tuberosity, linea aspera, and medial supracondylar line of the femur;

- the hamstring portion inserts, via a rounded tendon, onto the adductor tubercle and medial supracondylar line of the femur.

Key Features & Anatomical Relations

Overall, the adductor magnus muscle is found in the medial compartment of the thigh. It is a large, thick, triangular skeletal muscle and is composed of two portions:

- a laterally located adductor portion;

- a medially located hamstring (ischiocondylar) portion.

These two portions differ in terms of their origins, insertions, actions and their nerve supply, where:

- the adductor portion is supplied by the obturator nerve;

- the hamstring portion is supplied by the tibial division of sciatic nerve.

Furthermore, the most superior fibers of the adductor portion, which originate from the inferior pubic ramus and insert onto the gluteal tuberosity, are sometimes collectively referred to as the adductor minimus muscle.

The adductor magnus muscle is located:

- anterior to the semimembranosus, semitendinosus and biceps femoris muscles, and the sciatic nerve;

- posterior to the pectineus, adductor brevis and adductor longus muscles, and the deep femoral vessels;

- lateral to the gracilis muscle.

Along the insertion sites for the adductor magnus muscle, there are five gaps. From superior to inferior:

- the first to third gaps allow for the passage of the perforating arteries of the deep femoral artery;

- the fourth gap allows for the passage of the distal end of the deep femoral artery;

- the fifth gap, located between the insertion sites of the adductor and hamstring portions, is known as the adductor hiatus and allows for the passage of the femoral vessels.

The adductor magnus muscle contributes to the formation of the adductor canal, where the muscle forms its posterior boundary.

Actions & Testing

Overall, the adductor magnus muscle is involved in multiple actions:

- the adductor portion adducts and flexes the thigh at the hip joint;

- the hamstring portion extends the thigh at the hip joint (Moore, Dalley and Agur, 2009).

The adductor magnus muscle cannot be tested in isolation, therefore all of the muscles of the medial compartment of the thigh are tested simultaneously by adducting the thigh at the hip joint against resistance while lying in the supine position with the knee extended (Standring, 2016).

List of Clinical Correlates

- Groin strain

References

Moore, K. L., Dalley, A. F. and Agur, A. M. R. (2009) Clinically Oriented Anatomy. Lippincott Williams & Wilkins.

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