Barrack v. Haas: Patella Resurfacing: Rarely, if Ever, Necessary

This week’s Orthopaedic Crossfire® debate was part of the 33rd Annual Current Concepts in Joint Replacement® (CCJR®), Winter meeting, which took place in Orlando. This week’s topic is “Patella Resurfacing: Rarely, if Ever, Necessary.” For is Robert L. Barrack, M.D., Washington University School of Medicine, St. Louis, Missouri. Opposing is Steven B. Haas, M.D., Hospital for Special Surgery, New York, New York. Moderating is Thomas P. Sculco, M.D., Hospital for Special Surgery, New York, New York.

Dr. Barrack: For my first 10 years I resurfaced the patella almost always. Now I hardly ever do, and that was after I did a series of randomized trials that told me that there was very little, if any, advantage to doing it.

So, the data is really confusing, varied and contradictory.

Most studies show that the results are equivalent. At least as many studies indicate that routine resurfacing may have some advantages.

But the individual studies are underpowered, and the sample sizes are too small. I’m sure what you’re going to hear from Dr. Haas is about meta-analyses and registries. But if you look at all these meta-analyses what they would tell you is the reoperation rate is higher when you don’t resurface the patella.

The problem with the pooled literature is that many of these reviews include 30-year-old data which is really outdated. If we look at the registry data, you find the same thing.

The other problem is that patella resurfacing complications are vastly underreported. Usually there is not a good operation for the problems that you create. Those problems can be pretty significant and are more common than you think.

Pooled data can be misleading because the type of components used in surgery can dramatically impact the results. The best performing knee in the Swedish Registry only worked when you didn’t resurface the patella.

One of the major manufacturers actually promoted this knee. Said it was the best performer, but only when the patella was not resurfaced. The same implant, when resurfaced, did worse than average.

The Swedes don’t pay attention to this. They rarely resurface the patella in spite of the fact that they report it is more common to have to be revised. If the incidence of reoperation is higher in registries and meta-analyses, then why not just resurface the patella routinely?

The problem is that it’s not a benign or simple procedure.

Over resection, under resection, oblique resection, are all problems and AVN [avascular necrosis] is an occasional problem. And these all lead to negative sequalae.

How often do these occur?

Berend et al.’s (CORR, 2001) report from years ago showed in only 2.6 years that a lot of patellas were starting to fragment. While relatively few were revised, that was at 5 years. What’s going to happen at 10 years and 15 years?

In conclusion, patella resurfacing remains a debated topic.

Excellent results can be obtained with either approach.

Patella resurfacing is common in the U.S. It’s standard practice in some communities, but in the St. Louis area where Leo Whiteside practices, it’s really not done to a great extent.

I have never seen one of Leo’s patients need to come to me for a subsequent resurfacing. I would tell patients, “You might need a second operation, but it’s more than offset by the risk of complications of routinely resurfacing.”

I think the results are similar and surgical technique is important, but ultimately, it’s not whether or not you resurface the patella…I agree with Adolph Lombardi. I think five years from now we’re going to be doing mostly uncemented components without patella resurfacing.

Dr. Haas: If you like to re-operate, not resurfacing may be a good idea if you’re in Missouri…I didn’t realize the state animal is a mule…that’s actually interesting. But if you’re in Missouri, it’s probably a good idea.

If you have to re-operate on a patient in New York City, they’ll ask you, “Why didn’t you get rid of this the first time? You told me you were solving my problem.” I think you have to have a good discussion if you’re going to not resurface the patella and you have to pick the population you’re going to do it on and accept that you’re going to have to re-operate on them.

Initially not resurfacing the patella leads to higher revision rates and equal or more pain. So, why are we doing it? A meta-analysis (Nizard et al., CORR 2005) shows that un-resurfaced patellas had increased pain, greater reoperations, greater anterior knee pain.

Another 14 published studies, again, published in CORR by Parvizi, reported that non-resurfaced patellae had a greater incidence of anterior knee pain—8.7% required a secondary operation. So not insignificant and my patients don’t like to be operated on. Not resurfacing the patella led to lower satisfaction in that study.

Another meta-analysis that Pakos et al. did in 2005, 10 randomized controlled trials, 1,200 patients, patella resurfacing reduced the risk of reoperation and anterior knee pain.

A study by Bourne and Burnett (CORR 2004) looked at national registries, bilateral data, selective resurfacing reports and randomized trials…again, 13% needed reoperation compared to 5% with resurfaced patellas.

Randomized controlled trials. Two non-resurfaced patellas required subsequent reoperation, none in the resurfaced group and there were no complications in the patella resurfacing group (Campbell et al, JBJS-Br 2005).

Another study (Burnett et al., 2007). Patella resurfacing versus non-resurfacing. Bilateral cases…10-year minimum follow-up. The equivalent results—37% preferred the resurface; 22% preferred their non-resurfaced; and 41% no difference.

Randomized clinical trial—another one, patella resurfacing versus non-resurfacing, (Burnett et al., JBJS 2009), 78 total knee replacements. No difference in range of motion, Knee Society scores, satisfaction, but a reoperation rate more than three times as high with the non-resurfaced patellas. So, again, significantly higher.

Another randomized controlled trial (Fiddian & Murray, Knee Society 2009)—looking at large series of patients, many different centers in the UK. Reoperation rate significantly higher in the non-resurfaced group—4.1% and 1.9% with resurfacing.

Dr. Barrack’s study-patella resurfacing versus non-resurfacing, 88 total knees. No difference in range of motion, Knee Society scores, patella function and just no preference in the bi-lateral cases. So not a big difference.

And a prospective multi-center review (Tabutin et al., KSSTA 2005), almost 6,000 patients. Again, incidence of patellofemoral pain higher in the non-resurfaced group compared with the resurfaced group.

Another analysis, literature search, meta-analysis, systematic review and randomized studies combined (Calvisi et al., AOTS 2009), patella resurfacing reported with decreased anterior knee pain and a decreased reoperation rate.

We’re getting the theme of all these studies.

You heard about the Swedish Registry. It is correct. There was a 1.4 times higher cumulative revision rate in the 30,000 patients without patella resurfacing.

You look at the Australian Registry, again, the same concept. If you look at cumulative rate of revision, it is higher in the non-resurfaced group. If you look at the patellofemoral pain, it is also higher in the non-resurfaced group.

So, I’m thinking in conclusion, most people don’t like to be re-operated on.

If 3-5% are going to go back, my patients are not going to be happy. I think that if you resurface them you’re going to be happier with that result and not have to go back and re-operate.

I think patella resurfacing makes sense.

Moderator Sculco: I’ll turn to you, Robert. Do you subjectively notice any difference in the patients who have the patella replacement, looking back at when you did it more regularly, versus those you see now in your office come back without a resurfaced patella?

Dr. Barrack: No, I think that our techniques are better. The implants are more patella-friendly and we just rarely see problems with patella resurfacing. In terms of anterior knee pain or overall incidences of reoperation, the most important document, I think, in knee surgery in recent history, is the AAOS’s clinical guidelines on surgical management of osteoarthritis of the knee.

Their conclusion was that there is no clinical difference in anterior knee pain, in function, in satisfaction. The only difference was in reoperation rate and I think that’s an artificial number because surgeons poorly advised…if they’re not experienced with an un-resurfaced patella, will do a second operation, because an equal or higher number of patients with symptomatic patellas have been resurfaced—what are you going to do about it?

Just tell them to live with it.

I do think that Steve brings up a good point that there’s a medical/legal problem in places like New York…one of the many reasons that people avoid places like that.

Fortunately, Leo fought the battle for us so that most knees in St. Louis don’t have the patella resurfaced and he’s been there for 40 years and two or three of his fellows have been there for years, so there are tens of thousands of these knees and I’ve never subsequently resurfaced one of his knees or some of his higher volume fellows.

But I do take the point that if you’re in a community that’s very litigious, that’s unfortunate.

Moderator Sculco: Tell us a little bit more about your selection criteria. What percent of knees currently do you not resurface?

Dr. Barrack: Over 90%.

If someone has a deformed patella that doesn’t track well, or has aggressive inflammatory arthritis, those are accepted indications. If they have primarily patellofemoral arthritis and they’re older, and most of their pain is purely anterior knee pain.

Moderator Sculco: Do you denervate around the patella? Tell us about some of the technical aspects.

Dr. Barrack: There is some technique to it. We do cauterize the periphery, but more importantly we do a little bit of a lateral release and do a partial lateral facetectomy and don’t leave any overhanging bone.

When I do resurface a patella, I do the same thing. I think it’s important to do a partial release, enough to remove any bone that you don’t want to articulate and increase the contact forces superolaterally. Patients are going to have pain in that area whether or not you resurface the patella.

Moderator Sculco: Leo Whiteside has always said that there are certain implants that are patella-friendly and certain implants that are not. Do you believe that as well?

Dr. Barrack: Absolutely, the Swedish Registry shows that pretty clearly.

But the best performing implant in that registry is one of the top two-three company implants. The risk of revision varies from 0.4 to 2.0%, with certain components if you don’t use patella resurfacing. So, you should pick the right implant.

Moderator Sculco: Steve, Robert raises a lot of good questions about the problems we see with patella resurfacing…fracture, weakened patella substrate, fragmentation, avascularity…so there are negatives to it as well.

Dr. Haas: I would absolutely agree that we have not solved the patella problem.

And I don’t think the exact way we resurface the patellas is correct or the optimal way to do it. It’s just that if you compare it to not resurfacing, you don’t get less pain without the patella resurfacing, you end up with more operations.

There is one advantage, which I’m going to give you, is that you preserve bone. If you have a young patient, and if you’re operating on a 40-year-old or maybe even a 50-year-old, I think it’s certainly reasonable to have a discussion with them. They’re better off living with the pain because you’re saving bone for down the road.

Dr. Barrack: The reality is that the one statistic we hear every meeting in the last five years is 20% of patients don’t like their total knees. That’s the problem. It’s not because the patella wasn’t resurfaced.

Dr. Haas: That’s right, but that 20% is no lower if you don’t resurface it either.

Dr. Barrack: The conclusion of our AAOS clinical guidelines committee was that the results, the satisfaction, the pain, including anterior knee pain, was no different. So I’d advise you to review that.

Moderator Sculco: Okay, guys, I’m going to have to put the halt on here. I want to thank all the speakers today. Very good job.

Please visit www.CCJR.com to register for the 2018 CCJR Winter Meeting – December 12 – 15 in Orlando.

Senior Editor: Jay D. Mabrey, M.D., whose 35 year career in orthopedics included residency at Duke University Medical Center, service in the United States Army Medical Corps, Fellowship at the Hospital for Special Surgery and a long, distinguished career at Baylor University Medical Center where, in addition to his overall leadership at that institution, developed the Joint Wellness Program that helped patients get up after surgery more quickly, developed the first virtual reality surgical simulator for knee arthroscopy and chaired the FDA Orthopaedic Device Panel, is Orthopedics This Week’s newest contributing writer and editor.