Health Topics A-to-Z
Traumatic Dislocation of the Hip
What Is It? In a normal hip joint, the rounded top of the thigh bone (femur) fits into a cup-shaped socket in the pelvis called the acetabulum. This type of joint is called a ball-and-socket joint. When the top of the femur moves out of its normal position in the socket, the hip is said to be dislocated.