Muscles Of The Gluteal Region Study Guide Questions And Correct Answers

The Deep Muscles: Piriformis {Ans: The piriformis muscle is a key landmark in the gluteal region. It is the most superior of the deep muscles. Attachments: Originates from the anterior surface of the sacrum. It then travels infero-laterally, through the greater sciatic foramen, to insert into the greater trochanter of the femur. Actions: Lateral rotation and abduction. Innervation: Nerve to piriformis.}Clinical Relevance of the Superficial Muscles: Damage to the Superior Gluteal Nerve {Ans: The superior gluteal nerve innervates the gluteus medius and the gluteus minimus. These muscles have an important role in stablising the pelvis during walking. In a standing person, gluteus minimus and medius contract when the contralateral leg is raised, preventing the unsupported pelvis from dropping on that side. If the superior gluteal nerve is lesioned, and the muscles are paralysed, the pelvis becomes unsteady. The characteristic finding of gluteal muscle weakness is a positive Trendlenberg test. Trendelenberg Test In the Trendelenberg test, the patient is asked to stand unassisted on each leg in turn. In a positive test, pelvic drop will occur on the unsupported leg. Pelvic drop is can be recognised by looking for the level of the iliac crests on both sides. For