Muscles of the Medial Compartment of Thigh

Adductor Muscles

• Adductor longus may have a sesamoid bone called Rider's bone in its tendinous origin.
• Adductor brevis is another muscle in the compartment.

Adductor Magnus

• The largest muscle in the compartment.
• Has a tendinous origin from the body of pubis, specifically in the angle between the pubic crest and pubic symphysis.
• Also originates from the anterior surface of the body of pubis, outer surface of the ischio-pubic ramus, and the medial margin of the lower half of the body of pubis.
• The hamstring part originates from the intero-lateral part of the ischial tuberosity, while the adductor part originates from the outer part of the ischiopubic ramus.
• Inserts into the medial margin of the lower half of the femur, specifically the linea aspera in the middle 1/3 of the shaft.
• Also inserts into the line extending from the lesser trochanter to the upper part of the linea aspera.

Nerve Supply

• Anterior division of the obturator nerve supplies the adductor magnus.
• Hamstring part is supplied by the tibial component of the sciatic nerve.
• Pectineus is supplied by the anterior division of the obturator nerve and the femoral nerve.
• Gracilis is supplied by the anterior division of the obturator nerve.

Actions

• Adductor magnus, adductor brevis, and pectineus are all powerful adductors of the thigh and medial rotators of the thigh.
• The hamstring part of the adductor magnus helps in extension of the thigh.
• Gracilis is a flexor and medial rotator of the leg, and a weak adductor of the thigh.
• Pectineus flexes the thigh and adducts it.