Adductor magnus

At a glance

English

Adductor magnus

Latin (TA2)

Adductor magnus

System

Muscle

Region

Lower limb

Side

Paired, left and right

About the adductor magnus

Adductor magnus is a big, triangular sheet on the inner side of the thigh, lying behind the other adductors and in front of the hamstrings. It is really two muscles joined edge to edge. The adductor part, also called the pubofemoral part, belongs to the medial compartment; the hamstring part, or ischiocondylar part, behaves like a hamstring and is often grouped with them because of its origin, its nerve and its action.

The adductor part arises from the ischiopubic ramus. Its upper fibres are short and nearly horizontal and reach the femur on the gluteal tuberosity and the line below it, just medial to gluteus maximus; this upper slip is often separate enough to be named adductor minimus. Lower fibres slope increasingly downwards and attach by a broad aponeurosis along the linea aspera and the medial supracondylar line. The hamstring part comes from the ischial tuberosity, forms a thick vertical mass along the inner side of the thigh and ends in a rounded tendon on the adductor tubercle of the medial femoral condyle.

Where the muscle meets bone, its aponeurosis forms a series of tendinous arches. The upper ones let the perforating branches of the deep femoral artery pass to the back of the thigh. The lowest and largest, the adductor hiatus, lies between the aponeurosis and the tendon to the adductor tubercle; through it the femoral artery and vein pass behind the knee to become the popliteal vessels.

The whole muscle is a powerful adductor, especially when the legs come together from a wide stance. The adductor part also helps flex the hip, while the hamstring part extends it, as in rising from a squat or climbing. Their two nerves reflect their two origins: the obturator nerve for the adductor part and the tibial division of the sciatic nerve for the hamstring part. In many four-legged animals the muscle reaches the tibia; in humans that distal portion is thought to survive as the tibial collateral ligament of the knee.

Attachments, action and supply

Origin

Adductor part: inferior pubic ramus and ischial ramus. Hamstring part: ischial tuberosity.

Insertion

Adductor part: gluteal tuberosity, linea aspera and medial supracondylar line. Hamstring part: adductor tubercle of the femur.

Action

Adducts the thigh; the adductor part also helps flex the hip, and the hamstring part extends it.

Nerve supply

Adductor part: obturator nerve, posterior division (L2, L3, L4). Hamstring part: tibial division of the sciatic nerve (L4).

Blood supply

Deep femoral artery and its perforating branches, obturator artery, medial circumflex femoral artery, and branches of the femoral and popliteal arteries near the hiatus.