The ilioinguinal nerve, which arises from the L1 spinal nerve, innervates the skin on the medial aspect of the thigh, scrotum (or labia majora), and the mons pubis. It has been injured in this patient. The genitofemoral nerve splits into two branches: The genital branch supplies the scrotum (or labia majora) whereas the femoral branch supplies the skin of the femoral triangle. The subcostal nerve has a lateral cutaneous branch that innervates skin in the upper gluteal region, in addition to distribution over the lower part of the anterior abdominal wall. The Iliohypogastric nerve innervates the skin over the iliac crest and the hypogastric region. Spinal nerve T9 supplies sensory innervation to the dermatome at the level of T9, above the level of the umbilicus.