The Gluteal Region

Question 1

What are the three major gluteal mm., their innervation, blood supply and actions?

Answer 1

1) Gluteus maximus: inferior gluteal n., inferior gluteal a., extensor of the thigh on the trunk
2) gluteus medius: superior gluteal n. superior gluteal a., abduct thigh from the trunk and stabilize the pelvis
3) gluteus minimus: superior gluteal n. superior gluteal a., abduct thigh from the trunk and stabilize the pelvi

Question 2

Describe the Trendelenberg sign.

Answer 2

The necessity to throw you weight over the planted foot during gait

Question 3

What accounts for the appearance of the Trendelenberg sign?

Answer 3

The gluteus medius and minimus are not contracting to stabilize the pelvis in a horizontal plane with one foot off the ground.

Question 4

List the short lateral rotators of the thigh in order from superior to inferior.

Answer 4

1) Piriformis
2) Gemellus superior
3) Obturator internus (tendon of)
4) Gemellus inferior
5) Quadratus femoris.

Question 5

What is the nerve supply of the lateral rotators? their blood supply?

Answer 5

All the short rotators of the thigh are innervated by the sacral plexus L5-S1.

BLOOD SUPPLY?

Question 6

Which two structures from the pelvis pass medially to the sciatic nerve to supply the perineum?

Answer 6

The internal pudendal artery and pudendal nerve.

Question 7

What are the root values (cord levels) that comprise the sciatic nerve?

Answer 7

L4-S3.

Question 8

What may cause injury to the sciatic nerve?

Answer 8

Fractured hip or IM injection below the safe area of the gluteal region.