Candidates for Hip Resurfacing

Most patients with severe hip arthritis will have better outcomes with hip resurfacing than if they chose THR. I can technically perform hip resurfacing on most of these.

Frequently patients who consult me with regards to hip resurfacing tell me that they have been told by another surgeon that they are not a candidate and that their only option is a THR. Don’t trust any opinion on this topic unless the surgeon does at least 100 hip resurfacings a year. Even among very experienced surgeons who have done over 1000 cases, I am much more likely to perform resurfacing on most patients.

Most patients with a severely arthritic hip are in fact, good candidates. In the early days of hip resurfacing, it was clear that young men had the greatest success. Now after 23 years of scientific study and perfecting the art of hip resurfacing, most patient groups have similar outcomes, and they far surpass what is published for THR. 99% 17-year implant survivorship applies to virtually all patient groups: men/women, young/old, good/poor bone quality, osteonecrosis, dysplasia, bone loss/deformity.

If a surgeon tells you you are not a good candidate for some reason, please formally consult me. I can do hip resurfacing on most patients.

There are still some groups (representing < 1% of patients under 65) who are NOT good candidates:

• Lots of pain/ minimal objective findings of cartilage loss. These patients have a high chance of dissatisfaction with any joint replacement.
• Extensive bone loss of the femur (>half the head), or socket. Cases with up to ½ head loss can be done successfully with uncemented femoral implants plus bone graft. I have done extremely severe socket cases in the past with custom implants, but currently, they are not available due to the FDA bullying of implant companies. In my analysis, the laws regulating the use of custom implants allow these cases, but the FDA pressures implant manufacturers not to supply them.
• Elderly patients with osteoporosis

Why don’t more surgeons perform this operation?

Because they are technically unable and/or they are still gripped by the metal "fear factor" promoted by THR "thought leaders".

This is a very good question. I have been performing hip resurfacing since 1999 and have moved nearly completely away from doing standard THRs. Over my career, I have performed several thousand THR, but have now performed more than 7000 hip resurfacings and have come to prefer this operation for most patients with a severely damaged hip. Annually I may do over 400 hip resurfacings and less than 30 THR.

As I have gained experience with hip resurfacing, the outcomes in all patient groups are so much better and the failures are far fewer than I can achieve with THR. Initially, hip resurfacing was an operation that worked best in young men, but with time I have improved the technique to the point where all patient groups have a 99% 10-year implant survivorship. This means that already 10 years ago I was doing better with this operation in all patient groups than anyone can do with a THR.

The main problem for other surgeons is that this operation is much more technically difficult to perform. But more than 30 surgeons in the world have mastered it and can achieve excellent outcomes. The international resurfacing study group that I was part of demonstrated that hip resurfacing is a generalizable skill that other surgeons who dedicate themselves to this operation can develop. Nevertheless, many of these skilled resurfacing surgeons are still reluctant to perform this operation in certain groups of patients.

All skilled resurfacing surgeons offer this operation to men under 60 with osteoarthritis (OA), because the best implant survivorship has been demonstrated in this group; but women, patients with small bearing sizes, dysplasia, osteonecrosis, and older patients are still controversial. As mentioned, I have overcome these problems at least 10 years ago and prefer Hip resurfacing in all these patients.

However, many skilled THR surgeons have tried their hand at doing a few hip resurfacings and have subsequently given up because they could not achieve the same results as they could for THR. I think it takes at least 500 cases for an above-average THR surgeon to become proficient at this operation. In those initial cases, if surgeons with excellent technical skills stick to young men with OA, they can likely do better than they could do with THR. But, on the other hand, there are likely many surgeons who just are not good enough to pull it off, no matter how much they practice. After all, not all highly skilled NBA stars can compete with LeBron James. Just as in sports, in surgery, some are just inherently more skillful.

The other problem is the time commitment. For the beginner, hip resurfacing may take 3 hours, and the surgeon is exhausted. Meanwhile, he could have done an anterior THR in 45 minutes for the same reimbursement. My average time for a posterior THR or hip resurfacing is the same at 90 minutes. I also do not accept the very low fees offered by the government and some commercial insurers, because I do not do a 45-minute anterior THR.

Unfortunately, there is no higher reimbursing code for hip resurfacing, which is a more complex procedure with better outcomes. This is why I do not agree to contracted rates with the government plans and many insurers.

The other factor is the problem with metallosis. An exceedingly high failure rate (50% within 5 years) was seen for the notorious DePuy ASR THR system. This was a metal-metal THR. Even the hip resurfacing version of the ASR had a scary (30% 5-year) failure rate. This was a terrible implant approved by the FDA which has soured most surgeons on the idea of metal-metal bearings. Depuy is a very popular brand worldwide, and many DePuy surgeons implanted the ASR and were burned badly.

Hip resurfacing solved the dislocation problem, but surgeons were scared to try this more complex operation. The beauty of large metal-metal bearing THR is that these implants also solved the age-old dislocation problem of THR (still the #1 failure mode of THR) and were no more difficult to implant than any other THR. With the ASR, loosening, metallosis, and trunion corrosion problems, unfortunately, were very common and were not predicted in laboratory testing and the FDA clearance process before general release. This has been by far the single largest orthopedic implant disaster that I have witnessed in my career.

Large metal-metal THR versions of other manufacturers also had a somewhat higher failure rate than metal-plastic THR due chiefly to trunion corrosion. They have all been removed from the market. None compared to the magnitude of the ASR problem. Most surgeons erroneously concluded that the metal-metal bearing itself was the problem. Aside from the ASR, trunion corrosion was the main problem with the other brands. It turns out that when a very large cobalt chrome head is attached to a small titanium stem trunion, the forces driving corrosion are very high. If a smaller cobalt chrome head is used (as in standard metal-plastic THR) corrosion failure is much less (1-5% by 10 years), but the hip is unstable due to the unnaturally small bearing size. This is an ongoing dilemma with all THR.

Hip resurfacing does not have a trunion to corrode, but THR surgeons still claim metallosis is a high risk for hip resurfacing because they maintain that the bearing itself is the problem. Meanwhile, we have learned that abnormal bearing wear causing metallosis only occurs in hip resurfacing if the acetabular component is malpositioned. I have published a safe zone for placing the component and have demonstrated that we can reliably place the socket into this safe zone 100% of the time and that this completely prevents metallosis.

I have not had a single case of metallosis since 2009 in over 5000 cases. THR surgeons simply are ignoring this published data and continue to claim that metal-metal bearings cause metallosis in a high percentage of cases randomly. Based on the disastrous ASR experience, I can understand their fear. But I have solved the minor metallosis problem with hip resurfacing. THR trunion corrosion continues to result in 1-5% failures by 10 years in THR. Trunion corrosion results in a far more severe inflammatory process than metallosis from abnormal bearing wear.

Metal-metal resurfacing can cause metallosis if malpositioned. THR can result in trunion corrosion in 1-5% by 10 years, randomly. We suspect that ceramic heads are less likely to do this in THR, but the data is not in yet. Most surgeons including myself are using ceramic heads in THR for this reason.