EXECUTIVE SUMMARY

Hip arthroscopy patients with osteoarthritis are at higher risk of a two-year conversion to total hip replacement, according to the authors of a study.

  • The average time for hip arthroscopy patients until they underwent total hip arthroplasty was 1.12 years.
  • The study’s findings are similar to what researchers observed with procedures like knee arthroscopy on patients with knee arthritis.
  • Researchers recommend more research on the cost effectiveness of various types of procedures, including hip arthroscopy.

A study of Medicare data collected between 2005 and 2016 revealed hip arthroscopy patients with osteoarthritis recorded a 68.4% two-year conversion rate to total hip replacement.1

A surgery that results in another surgery within two years is a low-value procedure, says Alexander McLawhorn, MD, MBA, a study co-author and assistant attending at the Hospital for Special Surgery in New York City.

“We only looked at what happens if patients had hip arthroscopy in the setting of hip arthritis,” says McLawhorn, an assistant professor of orthopedic surgery at Weill Cornell Medical College. “We focused on an older population of people [older] than 65 years of age to see if this [surgery] is a good idea or not a good idea.”

The average time for hip arthroscopy patients with osteoarthritis before they underwent hip replacement surgery was 1.12 years, McLawhorn says. Previous research has focused on procedures like knee arthroscopy on patients with knee arthritis. Those investigators found those procedures are ill-advised, too. “We were curious to see if a similar [conclusion] held true for hip procedures,” McLawhorn says.

McLawhorn’s previous research revealed patient-reported outcomes for hip replacement after hip arthroscopy were not as positive as the patient-reported outcomes among people who underwent hip replacement without hip arthroscopy.2 “Hip arthroscopy is an evolving field,” McLawhorn acknowledges. “There are some conditions where hip arthroscopy is the most appropriate treatment.”

Research has not yet defined which patients benefit from hip arthroscopy, but McLawhorn believes it is an area worth exploring further.

“I don’t want to say that everyone who has underlying arthritis shouldn’t have that procedure, but it certainly begs further research and caution by surgeons,” he adds. “Surgeons need clear indications for who is going to get significant benefit from that procedure and whether it is a durable benefit from that procedure. I don’t think that has been figured out yet.”

When surgeons counsel patients about hip surgery, they come up with a cost-risk-benefit analysis. They also can discuss how hip replacement materials are durable, and the longevity of hip replacement has greatly improved when compared with 15 to 20 years ago, McLawhorn says.

“About 2005 is when most surgeons made the switch to the more durable plastic for hip replacement,” he explains. “Over the next five to 10 years, it became clear that plastic was going to be very durable and wearing at a very slow rate.” This improvement changes the cost-risk-benefit calculation for total hip replacement. It also draws some attention to whether hip arthroscopy is as beneficial in cases when patients will have to undergo total hip arthroplasty a short time later.

“If you do a hip preservation type of procedure for a patient who has arthritis, it needs to buy them quite a bit of runway,” McLawhorn says. “Make sure the outcomes of that procedure will give you 10 years or so of benefit before the patient needs hip replacement.”

There should be more research on the cost-effectiveness of various types of procedures. “How many years of good outcomes does a non-arthroplasty procedure need to give a patient to make delaying hip replacement worthwhile?” McLawhorn asks. “Certainly, we can complete a computer model to answer that question.”

In their investigation, McLawhorn and colleagues concluded arthroscopic hip surgery should be limited to conditions that would not require total hip replacement surgery. People with osteoarthritis and who underwent a hip arthroscopy procedure followed by total hip replacement experienced worse overall outcomes after hip replacement surgery.1

For example, they were at a significantly higher risk for a repeat hip replacement and hip dislocation. “They had a greater risk of the implant in the bone not incorporating. We saw they had a significantly increased risk of infection of their joint replacement,” McLawhorn says. “All of those are possible complications after hip replacement. Both groups of patients had those complications, but the percentage of patients who had arthroscopy were higher, and the odds of having those complications were higher.”

It is speculation to assign a cause, but McLawhorn and colleagues’ observational study showed associations between poor outcomes and undergoing a hip arthroscopy procedure when the patient had hip osteoarthritis.

“When you see these associations, you can speculate that when patients undergo multiple procedures that traumatize soft tissue around the hip joint, it can lead to issues with dislocation and infection,” McLawhorn says. “From our prior results in patient-reported outcomes research, anyone would agree that having two operations for the same problem is not going to result in high patient satisfaction rates.”

Some patients handled both procedures well. The study’s findings highlight the need for physicians to inform patients of the risks, especially if they are uncertain of the procedure’s outcome.

“Surgeons who are doing arthroscopy need to better define the patient population and characteristics of patients who are going to do well with hip arthroscopy in the setting of arthritis vs. those who will not do well, and will need to go on to hip replacement,” McLawhorn says. “We need carefully tailored treatments to specific conditions and patient characteristics.”

Leaders in the field of hip arthroscopy should help surgeons define the patient population that will benefit from this procedure, he adds. “There are some patients out there who really want to do whatever they can to save their own joint, and I very much understand that,” McLawhorn explains. “They might seek out hip arthroscopy to swing for the fences.”

Surgeons need to understand what patients are after. They can empathize with patients’ goals, but it also is important to clearly define the risks, especially the possibility of following one procedure with another in a short period. Often, surgeons will speak to a procedure’s benefits, but not underscore potential risks or downsides. “We all need to be better at doing this. Hopefully, this study will help surgeons speak to the potential downsides and risks of this operation,” McLawhorn says.

REFERENCES

  1. Malahias MA, Gu A, Richardson SS, et al. Hip arthroscopy for hip osteoarthritis is associated with increased risk for revision after total hip arthroplasty. Hip Int 2020; Mar 3;1120700020911043. doi: 10.1177/1120700020911043. [Online ahead of print].
  2. Konopka JF, Buly RL, Kelly BT, et al. The effect of prior hip arthroscopy on patient-reported outcomes after total hip arthroplasty: An institutional registry-based, matched cohort study. J Arthroplasty 2018;33:1806-1812.