Adductor Magnus Innervation -

In contrast, the hamstring part of the muscle originates from the ischial tuberosity and inserts via a thick tendon into the adductor tubercle of the femur. Functionally and developmentally, this portion behaves like a hamstring muscle, contributing to hip extension. Consequently, it receives its nerve supply from the tibial division of the sciatic nerve, specifically from the L4 spinal nerve root. This dual innervation makes the adductor magnus a "composite" or "hybrid" muscle, similar to the pectineus or the brachialis.