acetabulum

anatomy

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Last updated

July 23, 2026

Quick Summary

The acetabulum is a cup-shaped socket in the hip bone that forms part of the hip joint. This joint connects the thighbone, or femur, to the pelvis. The head of the femur rests within the acetabulum, allowing for free rotation of the leg. In humans, the acetabulum is formed by the fusion of three bones: the ilium, pubis, and ischium. This deep cavity is crucial for weight-bearing and locomotion, enabling mammals to hold themselves off the ground and facilitating efficient movement like running and leaping.1234

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human skeleton
Pectoral girdle and pelvic girdle
…contributes a part of the acetabulum, the deep cavity into which the head of the thighbone, or femur, is fitted. The flaring upper part of the girdle is the ilium; the lower anterior part, meeting with its fellow at the midline, is the pubis; and the lower posterior part is…
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…contributes a part of the acetabulum, the deep cavity into which the head of the thighbone, or femur, is fitted. The flaring upper part of the girdle is the ilium; the lower anterior part, meeting with its fellow at the midline, is the pubis; and the lower posterior part is…
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bone disease
Abnormal stress on bone
…part of the joint, the acetabulum, loses the mechanical stimulus for normal growth and development because the ball part of the joint, the head of the femur, does not rest in the joint. The acetabulum and a large part of the pelvis develop poorly or not at all, whereas the…
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…part of the joint, the acetabulum, loses the mechanical stimulus for normal growth and development because the ball part of the joint, the head of the femur, does not rest in the joint. The acetabulum and a large part of the pelvis develop poorly or not at all, whereas the…
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pelvis
…a triangular suture in the acetabulum, the cup-shaped socket that forms the hip joint with the head of the femur (thighbone). The ring made by the pelvis functions as the birth canal in females.
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…a triangular suture in the acetabulum, the cup-shaped socket that forms the hip joint with the head of the femur (thighbone). The ring made by the pelvis functions as the birth canal in females.
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