Both parts of the ilium present numerous anatomical landmarks that mostly serve as attachment sites for various muscles and ligaments. The wing of the ilium has two surfaces - sacropelvic and gluteal surfaces.

The sacropelvic surface is found on the posteroinferior inner aspect of the bone. It is positioned posterior and inferior to the arcuate line. The sacropelvic surface is directed against the sacrum. It features two landmarks:
- The auricular surface is an ear-shaped surface that articulates with the same-named surface of the sacrum, forming the sacroiliac joint;
- The iliac tuberosity is the roughened area that is found posterosuperior to the auricular surface. It serves as the attachment site for the sacroiliac ligaments.
The gluteal surface is the outer surface of the wing bounded by the iliac crest superiorly and acetabulum inferiorly. It presents three rough, irregular lines called the gluteal lines. These lines are not direct attachment sites of the gluteal muscles, but they help better understand where these muscles attach to the bone.
- Anterior gluteal line - oblique line that goes in the posteroinferior direction from the iliac tubercle.
- Posterior gluteal line - the most vertical of the gluteal lines; it is found on the posterior aspect of the gluteal surface; it goes from the iliac crest in the posteroinferior direction towards the posterior inferior iliac spine.
- Inferior gluteal line - horizontal line found just superior to the acetabulum.

The gluteus minimus muscle originates between the anterior and inferior gluteal lines, while the gluteus medius arises between the anterior and posterior gluteal lines. And finally, the origin site of the gluteus maximus muscle is found posterior to the posterior gluteal line.

The wing of the ilium in the superior direction is limited by the iliac crest - the curved superior border of the bone. The iliac crest at both ends terminates with bony projections. Moreover, below the mentioned projections are two more similar projections.

Anterior superior iliac spine - upper anterior projection that is found at the anterior end of the iliac crest; serves as the attachment site for the sartorius muscle and inguinal ligament.
Anterior inferior iliac spine - blunt projection on the anterior border of the wing of the ilium (superior to the acetabulum); it is found below the anterior superior iliac spine; the rectus femoris and the iliofemoral ligament attaches to this landmark.
Posterior superior iliac spine - upper posterior projection that is found at the posterior end of the iliac crest; it serves as the attachment site for the gluteus maximus muscle.
Posterior inferior iliac spine - sharp projection on the posterior border of the wing of the ilium (posteroinferior to the auricular surface); it is found below the posterior superior iliac spine; this landmark is an attachment site for the sacrotuberous ligament.

The outer and inner aspects of the iliac crest are limited by two roughened margins known as the external lip and internal lip. The outer lip bulges laterally and forms a thickening at its anterior aspect called the iliac (cristal) tubercle.

The bony part below the anterior aspect of the iliac crest that goes to the acetabulum is known as the iliac pillar (acetabulo-cristal buttress). It is a vertically located thickening of the bone that is limited anteriorly by the anterior border of the wing and posteriorly by an imaginary line drawn from the iliac tubercle.

The anterior aspect of the inner surface of the wing features a relatively shallow and smooth concavity known as the iliac fossa. The iliacus muscle fills the fossa.

Below the fossa is a prominent bony ridge called the arcuate line. It participates in forming the pelvic inlet - the boundary line between the false pelvis and the true pelvis. The arcuate line goes from the anterior aspect of the auricular surface to the site where the ilium meets the pubis.

The iliopubic (iliopectineal) eminence is an elevation that marks the site where the pubis unites with the ilum. It is found lateral to the arcuate line.

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Ilium (landmarks)