The hip consists of two bones: the thighbone (femur) and the hip (pelvis). The femur and the pelvis come together to form the hip joint (iliofemoral). The thighbone is a long bone running from the knee up to the hip with a head shaped like a ball to fit neatly into a socket on the hip (acetabulum). Inside the socket is a flexible rim of soft tissue called the labrum, which helps increase the stability of the hip. Surrounding the hip joint is a joint capsule and multiple ligaments that help strengthen the hip joint.