The coxal bone, also known as the hip bone, is formed by the fusion of three bones: the ilium, the ischium, and the pubis. These bones fuse together during adolescence to create the strong and stable structure of the hip bone.
Ilium: The ilium is the largest and most superior part of the coxal bone. It forms the broad, flared portion of the hip bone and provides attachment sites for several muscles.
Ischium: The ischium is located posteroinferiorly and forms the lower and back part of the hip bone. It is the part of the hip bone that you sit on.
Pubis: The pubis is the anterior part of the hip bone. It meets the pubis of the opposite hip bone at the pubic symphysis, a cartilaginous joint.
These three bones fuse at the acetabulum, the socket that articulates with the head of the femur to form the hip joint. This fusion provides the necessary strength and stability for weight-bearing and movement.