To The Editor:
I am an orthopaedic resident entering an adult reconstruction fellowship, and I participated in a lively debate at the University of Oklahoma Journal Club regarding the article "Total Knee Arthroplasty for Patellofemoral Arthritis" (2002;84:1977-81), by Mont et al. The study showed excellent results in twenty-eight of thirty patients treated with primary total knee arthroplasty for severe patellofemoral arthritis with minimal if any arthritis in the medial and lateral compartments.
Most residents and attendings had an opinion on this article. My opinion is that this study provides further support for the belief that total knee arthroplasty can be used to address the patellofemoral joint. Many believe that a knee replacement should not be performed unless the medial or lateral compartment is involved. I have had a small amount of experience with knee replacement for the treatment of severe patellofemoral disease and have been pleased with the results.
My current treatment regimen is to manage these patients as if they have patellofemoral syndrome—i.e., with closed-chain quadriceps strengthening exercises and hamstring stretching supervised by a physical therapist and with reduction of activities that, according to the patient, irritate the joint. I think that if a patient has extreme radiographic changes and is over fifty or fifty-five, total knee arthroplasty is a viable option.
I see a large population of patients with anterior knee pain. The vast majority are middle-aged women. There are a large number of these women between forty and fifty-five with marked degenerative changes in the patellofemoral joint. I would be interested to hear Dr. Mont's suggestions regarding treatment options after failure of nonoperative therapy.
One final thought concerns resurfacing of the patella. I think that this article lends some support to the idea of seriously considering patellar resurfacing during total knee arthroplasty if degenerative changes of the patella are noted intraoperatively.
M.A. Mont and S. Haas reply:
We appreciate the comments by Dr. Hanby, who offered the opinion that our article further supports the idea that total knee arthroplasty can be used to address the patellofemoral joint. This belief is also supported by recently published articles by Laskin and van Steijn
1 and by Parvizi et al.
2 . The opinion expressed by many at Dr. Hanby's institution that a total knee arthroplasty should not be performed unless the medial or lateral compartment is involved is generally a sound one. However, the patients in our study and in studies by others had severe debilitating pain that was not responsive to other methods and had severe grades of patellofemoral arthritis that would not have been responsive to many other treatment methods aimed at trying to save the patellofemoral joint.
Over the past ten years, there has been a resurgence in interest in patellofemoral arthroplasties. A number of authors have reported good and excellent midterm results with these types of arthroplasties. Also, a number of manufacturers are supporting further work on the development of prostheses that may have more durable results than what had been reported in the literature when our study was begun (in the late 1980s). New patellofemoral prostheses may become another and possibly more viable option than performing an entire knee replacement, which does appear to be a drastic (although effective) solution for these patients.
We agree with Dr. Hanby's regimen of using quadriceps and hamstring strengthening and stretching methods and various other nonoperative treatment modalities to try to forestall operative procedures in these patients. We also agree that total knee arthroplasty is a viable option for patients with extreme radiographic changes, although it is hard to choose an age range, such as his suggestion of fifty or fifty-five years, since age is a relative term.
The treatment of patients with anterior knee pain needs to be individualized. Certainly, there is a whole gamut of options depending on alignment issues, degree of degeneration, and soft-tissue considerations. In younger patients, we would try alternative procedures such as proximal or distal realignment with attempts at unloading the patellofemoral joint (Fulkerson or Maquet procedures) and other attempts to address cartilage damage (OATS procedure or Pridie procedure).
We caution that, in young patient populations, patellofemoral arthroplasty or total knee arthroplasty should be used as a last resort.
Whether or not to resurface the patella is also a controversial topic, with more than sixty articles on the subject having been published. We do not believe that our report supports or provides evidence against the need for resurfacing during routine total knee arthroplasty. Anecdotally, one recent study
3 described total knee arthroplasties performed without patellar resurfacing for isolated patellofemoral osteoarthritis. Although we do not agree with this approach to the problem, those authors recommended it despite the fact that their study included only short-term follow-up (twenty months on average) and 36% of the knees still had anterior knee pain. Thus, there is not necessarily one approach to this problem.
For the interested reader, there is a patellofemoral arthroplasty group that deals strictly with patellofemoral disorders and can be contacted at the following address: The Orthopaedic Center, 9711 Medical Center Drive, Suite 201, Rockville, MD 20850.