Inferior Gluteal Nerve
The Inferior Gluteal nerve leaves the pelvis via the infrapiriformal foramen. It immediately divides into two or three branches which fan out on the deep surface of the gluteus maximus. The inferior gluteal nerve is the sole innervation to the gluteus maximus.
Although uncommon, injury to the inferior gluteal nerve will lead to loss of strength of extension of the thigh, especially from a seated position. Activities sush as rising from the seated position, or climbing stairs, are more compromised by gluteus maximus paralysis than is walking. The gluteus maximus is used very little during walking. Some authors report no effect on gait of a paralyzed gluteus maximus. Some authors state that the patient tends to lean backward at the moment of heel strike. To test for damage to the inferior gluteal nerve, ask the prone patient to flex the knee, and then raise the thigh against resistance.