Acetabulum Flashcards

Study the acetabulum's structure, articular surfaces, bony landmarks, ligament attachments, hip joint relationships, and clinical anatomy.

Card 1 of 30Question

What is the acetabulum?

A deep, cup-shaped socket on the lateral surface of the hip bone that receives the femoral head.

In This Section

1. What is the acetabulum?

A deep, cup-shaped socket on the lateral surface of the hip bone that receives the femoral head.

2. Which three bones contribute to the formation of the acetabulum?

The ilium, ischium, and pubis.

3. Which bone forms the largest portion of the superior acetabulum?

The ilium.

4. Which bone forms most of the posteroinferior acetabulum?

The ischium.

5. Which bone contributes to the anteroinferior acetabulum?

The pubis.

6. In which directions does the acetabular opening face?

Laterally, inferiorly, and anteriorly.

7. What type of synovial joint is formed between the acetabulum and femoral head?

A ball-and-socket synovial joint.

8. What is the lunate surface of the acetabulum?

The horseshoe-shaped articular surface that articulates with the femoral head.

9. What type of cartilage covers the acetabular lunate surface?

Hyaline articular cartilage.

10. Which region of the acetabulum is particularly important for transmitting body weight?

The superior portion of the lunate surface, forming the weight-bearing acetabular roof.

11. What is the acetabular fossa?

The central, nonarticular depression surrounded by the lunate surface.

12. What tissue normally occupies much of the acetabular fossa?

Fibrofatty tissue, commonly called the acetabular fat pad.

13. What is the acetabular notch?

An interruption in the inferior acetabular rim between the ends of the lunate surface.

14. Which ligament bridges the acetabular notch?

The transverse acetabular ligament.

15. What is the acetabular labrum?

A fibrocartilaginous ring attached to the acetabular rim.

16. What is the principal function of the acetabular labrum?

It deepens the socket and creates a stabilizing seal around the femoral head.

17. How does the transverse acetabular ligament relate to the acetabular labrum?

It connects the inferior ends of the labrum across the acetabular notch.

18. Where does the ligament of the head of the femur attach within the acetabulum?

To the margins of the acetabular notch and the transverse acetabular ligament.

19. Which artery may enter the hip joint through the acetabular notch?

The acetabular branch of the obturator artery.

20. What is the triradiate cartilage?

A Y-shaped growth cartilage separating the developing ilium, ischium, and pubis within the acetabulum.

21. What happens to the triradiate cartilage during skeletal maturation?

It ossifies, allowing the three components of the hip bone to fuse.

22. Where does the fibrous capsule of the hip joint attach on the pelvic side?

Around the acetabular rim, outside the attachment of the acetabular labrum.

23. Which arteries contribute to the blood supply of the acetabular region?

Branches of the obturator, superior gluteal, and inferior gluteal arteries.

24. What is acetabular dysplasia?

Abnormal development of the acetabular socket resulting in insufficient coverage of the femoral head.

25. What is the center-edge angle of Wiberg used to assess?

The degree of lateral acetabular coverage of the femoral head on pelvic radiographs.

26. What is the significance of the anterior and posterior columns in acetabular fracture anatomy?

They are major structural regions used to describe and classify acetabular fractures.

27. Which acetabular region is commonly fractured during a posterior hip dislocation?

The posterior wall of the acetabulum.

28. What is femoroacetabular impingement?

Abnormal contact between the proximal femur and acetabular rim during hip movement.

29. What is pincer-type femoroacetabular impingement?

Impingement associated with focal or global acetabular overcoverage of the femoral head.

30. Why can displaced acetabular fractures lead to post-traumatic osteoarthritis?

Disruption of the articular surface can alter hip joint congruence and load distribution.