How is it done: When a posterior approach is used, the patient has to lie on the side. So, the body is held in place with vertical posts or supports. A 6 to 8 inch long curved skin cut made behind the hip joint in the butt. The large muscle close to the skin (gluteus maximus) is split. The deep muscles are then reached and detached. The small muscles that control hip rotation are also detached. The joint capsule that wraps the ball and socket hip joint is then exposed. The joint capsule is cut open and the hip joint is reached.

The bone and socket of the hip joint is exposed and replaced. Afterwards, the length of the operated leg is checked against the good leg (below it) by feeling the knee caps to make sure they are even. A tube (drain) is placed inside the wound so that any bleeding afterwards will exit the body. The split and detached muscles and soft tissue are repaired with stitches using sutures. The surface skin is closed up with metal staples. Bandages (dressings) are placed over the wound. A wedged shaped pillow is then placed between the legs to keep the legs apart. The patient is turned from the side to a face up position. The patient is moved from the operating room table to a bed and wheeled to the recovery room. Usually, an x-ray is taken in the recovery room to ensure that the implants are placed in the appropriate positions.

The posterior approach is the most common surgical approach used in total hip replacement. The advantage of this approach is that the hip joint is well exposed. The surgeon can see everything in the process of getting to the hip joint. Any bleeding can be stopped and the sciatic nerve is avoided. The replacement of the diseased ball and socket joint is performed under excellent vision. Another advantage is that the muscle that control the outward spreading (abduction) of the leg is not cut and so the muscle power is not lost.