medial intermuscular septum of thigh medial intermuscular septum of thigh the medial intermuscular septum of thigh is a fold of deep fascia in the thigh. medial intermuscular septum of thighcross-section through the middle of the thighdetailsidentifierslatinseptum intermusculare femoris medialeta98a04.7.03.005ta22692fma58749anatomical terminology it is between the vastus medialis, and the adductors and pectineus. it separates the anterior compartment of the thigh from the medial compartment of the thigh.