For other arcuate lines, see arcuate line

Arcuate line

In anatomy, an arcuate line is any structure that is curvilinear.* Arcuate line * Arcuate line...

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The arcuate line of the ilium

Ilium (bone)

The ilium is the uppermost and largest bone of the pelvis, and appears in most vertebrates including mammals and birds, but not bony fish. All reptiles have an ilium except snakes, although some snake species have a tiny bone which is considered to be an ilium.The name comes from the Latin ,...

 is a smooth rounded border on the internal surface of the ilium. It is immediately inferior to the iliac fossa

Iliac fossa

The iliac fossa is a large, smooth, concave surface located on the internal surface of the ilium...

 and Iliacus muscle.

It forms part of the border of the pelvic inlet

Pelvic inlet

The pelvic inlet or superior aperture of the pelvis is a planar surface which is typically used to define the boundary between the pelvic cavity and the abdominal cavity .Its position and orientation relative to the skeleton of the pelvis is anatomically defined by its...

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In combination with the pectineal line

Pectineal line

On the posterior surface of the femur, the intermediate ridge or pectineal line is continued to the base of the lesser trochanter and gives attachment to the pectineus muscle....

, it comprises the iliopectineal line

Iliopectineal line

The iliopectineal line is the border of the iliopubic eminence. It can be defined as a compound structure of the arcuate line and pectineal line...

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The arcuate line marks the border between the body (corpus) and the wing

Wing of ilium

The wing of ilium is the large expanded portion which bounds the greater pelvis laterally. It presents for examination two surfaces—an external and an internal—a crest, and two borders—an anterior and a posterior.-External surface:...

 (ala) of the ilium, and, running inferior, anterior, and medial from the auricular surface to the area corresponding to the acetabulum

Acetabulum

The acetabulum is a concave surface of the pelvis. The head of the femur meets with the pelvis at the acetabulum, forming the hip joint.-Structure:...

, it also indicates where weight is transferred from the sacroiliac joint

Sacroiliac joint

The sacroiliac joint or SI joint is the joint in the bony pelvis between the sacrum and the ilium of the pelvis, which are joined together by strong ligaments. In humans, the sacrum supports the spine and is supported in turn by an ilium on each side...

 to the hip joint.