Minimally Invasive Hip & Knee Replacement Surgery Commentary

Jonathan P. Garino, MD, Associate Professor
University of Pennsylvania School of Medicine

Patient Expectations: Faster Recovery & Less Discomfort

Research in musculoskeletal science has brought about revolutionary changes in the ability to deliver high quality life-altering joint replacement procedures. Recent advances have introduced better bearing materials to reduce wear and greatly increase serviceable life. These new materials have been improved to such a degree that many young and active patients can avoid revision of their prosthesis for the rest of their lives. Better designs have increased stability and function so the implant also feels more natural to the patient.

Recent trends have focused on improved rehabilitation and pain management to accelerate post-surgery recovery. Employing new surgical techniques to reduce the size of the incision and damage to underlying structures has been the primary advance toward this goal. These new techniques are known as MIS or Minimally Invasive Surgery. While these improvements have a real theoretical advantage, there are several things to keep in mind. First, at 3 months following surgery, there seems to be no difference in the comfort and function of patients having conventional surgery and those having an MIS procedure. With limited visibility afforded to the surgeon, MIS techniques have a risk of increased complications including sub-optimal device placement. This can negatively impact the long term-success of the replacement as well as it’s short-term function.

As such, patients need to be open minded and have an appreciation that optimally placed implants trump a fast recovery time. In joint replacement procedures the surgeon must negotiate his/her way through or around muscles and tendons and then cut away bone from the hip or knee and a replacement implant is attached to the bone. Make no mistake, this is not minimally invasive surgery. It is actually MAXIMALLY invasive and is probably the source of the vast majority of post-operative discomfort. My philosophy is to do the surgery as safely and as effectively as possible through the smallest incision possible. With that I would suggest that we refer to replacements performed through small incisions as Minimal Incision Surgery. This is probably the most accurate assessment of our current techniques and should temper patient expectations that these procedures will give you the hip or knee you had 20 years ago a week after the surgery. Although recoveries are much faster these days, the body does require some time to make repairs. Stressing those repairs before an adequate degree of healing has occurred may jeopardize the long-term success of the implant, or, more commonly, serve to disappoint a patient with expectations that are too high.