Question
The pelvic bones articulate with the femur at the:
A. Pubic symphysis
B. Obturator foramen
C. Acetabulum
D. Sacrum
Answer
C. Acetabulum is where the hip bone articulates with the femur.
The rounded head of the femur fits into the cup-shaped acetabulum on the lateral side of the hip bone, forming the hip’s ball-and-socket joint. The ilium, ischium, and pubis converge to form this socket.
Why the other choices are incorrect
- Pubic symphysis: joins the left and right pubic bones anteriorly.
- Obturator foramen: a large opening formed by the pubis and ischium; it is not the socket for the femoral head.
- Sacrum: articulates with the hip bones at the sacroiliac joints, not directly with the femur.
The correct choice is C, acetabulum.
Evidence boundary
The question uses “pelvic bones” in the wording of the Visible Body instructor manual. The direct articular relationship is specifically between the femoral head and the acetabulum of a hip bone. This answer distinguishes that joint surface from the wider pelvis and from the neighboring sacroiliac and pubic articulations.
Sources
These references support the concepts and methods used in the explanation above.