Doctors and researchers are studying the pros and cons of the minimally invasive (MI) operation. Right now it’s being used to replace hip and knee joints. They are comparing how long it takes patients to recover. Other results are measured by how much blood loss occurs, how long the operation takes, and how soon patients leave the hospital.

Some doctors point out that "minimally invasive" doesn't always means minimally disruptive. It's not minimally invasive if the tendons and muscles are cut and moved out of the way no matter how small the skin incision is.

Making a small opening makes it harder for surgeons to find the true margin of the hip socket. The skin along either side of the MI is more likely to tear. This is most likely to happen when the diseased joint is taken out and the edges of the bone are filed smooth.

Many doctors are taking a "wait-and-see" approach. Until more studies are done to compare the standard method to the minimally invasive surgery, doctors will continue to use the traditional incision.