Muscle · Hips

Pectineus

Musculus pectineus

A flat quadrangular muscle high in the groin, forming the floor of the medial part of the femoral triangle between psoas major and adductor longus. It runs from the pecten of the pubis down and back to the pectineal line of the femur, so it both flexes and adducts the hip — a hybrid that sits on the border between the flexor and adductor compartments, a position reflected in its variable nerve supply. It is the first muscle you cross when moving from the front of the hip to the inner thigh, and it lies directly beneath the femoral artery, vein and nerve — anatomy that governs how it is approached rather than an interesting aside. Note that pectineus does not appear in the founder's document, so this record carries descriptive anatomy only and no clinical framing.