ilium (yellow colour) At puberty,three bones are hip bone ischium separated by cartilage.At adult. cartilage ossifies into bone pubis (red colour) lliac crest Anterior superior lliac tuberosity iliac spine ilium posterior lliac fossa superior iliac spine pubis ischiun Auricular surface Lateral aspect Medial aspect hip bone ilium (yellow colour) ischium pubis (red colour) Lateral aspect Medial aspect Iliac crest Anterior superior iliac spine Iliac fossa Auricular surface Iliac tuberosity ilium ischium pubis posterior superior iliac spine At puberty, three bones are separated by cartilage. At adult, cartilage ossifies into bone