Mini-Midvastus Incision for Knee Joint Replacement

This is the second study by Dr. Richard Laskin from Cornell University on the use of a new approach to the minimally invasive (MI) total knee replacement (TKR). MI means a small incision is made to complete the operation. With MI, fewer structures are cut or disrupted.

The first study was a pilot study to see the results with a few patients. Dr. Laskin used a mini-midvastus approach. This means the cut was made along the front of the leg from just above the kneecap (patella) and slightly off center, straight down, and a short way below the patella. The patients had an excellent result.

In this follow-up study, 100 TKRs were done with this same method. The purpose of the study was to find out:

  • Would the results be just as good with a larger number of patients?
  • Is there any harm to the patient from this approach?
  • Does body mass index (BMI) make a difference?
  • Just how long of a skin incision is needed?
  • Are there cases when the mini-midvastus incision shouldn't be used?

    Dr. Larkin reports age, gender, and body weight didn't make a difference in the outcomes of this study. The length of the incision was based on how large the person's patella was. Taller patients had larger kneecaps and longer incisions. The author states the final length of the incision isn't important. Limiting the surgical trauma is the real goal.

    The only patients who are not good candidates for the mini-midvastus incision are those who have fixed (unchangeable) knock-knees. All the other patients had a good to excellent result.



    References: Richard S. Laskin, MD. Minimally Invasive Total Knee Arthroplasty. In Clinical Orthopaedics and Related Research. November 2005. No. 440. Pp. 54-59.