Knees for You Guide to Knee Replacement

No statistical learning curve found with MIS UKA

Link  http://www.orthosupersite.com/view.asp?rID=26798

By Dr. Hamilton

March 2008

SAN FRANCISCO - While proponents of minimally invasive procedures cite a learning curve in which complications decrease as surgeon experience increases, a new study finds no significant improvement in the revision and reoperation rates of minimally invasive unicompartmental arthroplasty with increased experience.

William G. Hamilton, MD, and colleagues retrospectively reviewed 445 patients who had minimally invasive unicompartmental arthroplasty (MIS UKA) performed by four surgeons at the same institution using the same implant design. A 3.2-year follow-up revealed a 5.8% overall revision rate, an 8.1% nonrevision reoperation rate and an overall reoperation rate of 12.6%.

Further analysis of the group during the first 2 years postop showed that the first 254 patients had a 3.8% revision rate and a 6.8% reoperation rate. A review of the second 253 patients revealed similar findings, with a 3.8% revision rate and a 6.7% reoperation rate.

"I think probably what the take home message should be is that the learning curve for this procedure may not exist and a baseline rate of revision and nonrevision reoperation should be expected with this prosthesis and surgical technique," Hamilton said during his presentation.

For more information:

• Hamilton WG, Engh, CA, Ameen D, et al. Learning curve with minimally invasive unicompartmental arthroplasty. Paper #62. Presented at 75th Annual Meeting of the American Academy of Orthopaedic Surgeons. March 5-9, 2008. San Francisco.