That's correct! The ischium does articulate with both the ilium and pubis. Here's why:

* Ilium: The ischium joins with the ilium at the acetabulum, which is the socket that forms the hip joint.

* Pubis: The ischium joins with the pubis at the ischiopubic ramus.

Together, the ilium, ischium, and pubis make up the os coxae, or hip bone. The os coxae on each side articulates with the sacrum at the sacroiliac joint, forming the pelvic girdle.