Ischium Flashcards

Study the ischium's body, ramus, tuberosity, spine, sciatic notch, muscle attachments, ligament relationships, and clinical anatomy.

Card 1 of 26Question

What is the ischium?

The posteroinferior portion of the hip bone, contributing to the acetabulum and obturator foramen.

In This Section

1. What is the ischium?

The posteroinferior portion of the hip bone, contributing to the acetabulum and obturator foramen.

2. What are the two principal anatomical parts of the ischium?

The body and the ramus.

3. Which region of the acetabulum is formed primarily by the ischium?

The posteroinferior portion.

4. Which part of the pubis joins the ischial ramus?

The inferior pubic ramus.

5. What is the ischiopubic ramus?

The continuous bony bar formed by the ischial ramus and inferior pubic ramus.

6. Which opening is bounded inferiorly by the ischiopubic ramus?

The obturator foramen.

7. What is the ischial tuberosity?

A large, roughened bony prominence on the inferior aspect of the ischium.

8. What is the principal weight-bearing function of the ischial tuberosity?

It supports much of the body's weight during sitting.

9. Which hamstring muscles originate from the ischial tuberosity?

Semitendinosus, semimembranosus, and the long head of biceps femoris.

10. Which part of adductor magnus originates from the ischial tuberosity?

The hamstring part of adductor magnus.

11. Which ligament attaches to the ischial tuberosity?

The sacrotuberous ligament.

12. What is the ischial spine?

A pointed bony projection extending posteromedially from the ischium.

13. Which two sciatic notches are separated by the ischial spine?

The greater and lesser sciatic notches.

14. Which ligament attaches to the ischial spine?

The sacrospinous ligament.

15. Which muscle originates from the ischial spine?

The superior gemellus muscle.

16. Which muscle originates near the superior border of the ischial spine on its pelvic surface?

The coccygeus muscle.

17. Which anatomical landmark is used to assess fetal station during vaginal examination?

The ischial spines.

18. Which nerve passes close to the ischial spine before entering the lesser sciatic foramen?

The pudendal nerve.

19. Which artery accompanies the pudendal nerve around the ischial spine?

The internal pudendal artery.

20. Which ligament forms the posterior boundary of the lesser sciatic foramen?

The sacrotuberous ligament.

21. Which muscle originates from the external surface of the ischial tuberosity near the lesser sciatic notch?

The inferior gemellus muscle.

22. Which deep hip muscle originates from the external surface of the ischium around the obturator foramen?

The obturator externus muscle.

23. Which muscle originates partly from the medial surface of the ischiopubic ramus?

The obturator internus muscle.

24. What is ischiogluteal bursitis?

Inflammation of the bursa between the ischial tuberosity and overlying gluteus maximus.

25. What is a common mechanism of ischial tuberosity avulsion fracture?

Sudden, forceful hamstring contraction, particularly in adolescent athletes.

26. Why is the ischial spine an important landmark for a pudendal nerve block?

The pudendal nerve passes close to the spine as it courses around the sacrospinous ligament.