The patient presented with loss of extension at knee joint with decreased sensation over anterior aspect of thigh. The nerve damaged is:

Femoral nerve supplies the extensors at knee joint and skin over the anterior aspect of thigh as well. Injury of the femoral is uncommon but may be injured by a stab, gunshot wounds, during hip operations or a pelvic fracture leading to - Motor loss: Poor flexion at the hip joint, because of paralysis of the iliacus and saorius muscles. Inability to extend the knee, because of paralysis of the quadriceps femoris. Sensory loss: over the anterior and medial aspects of the thigh over the medial side of the leg and foot up to the back of the great toe