A New Replacement for Hip Replacements

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Per-Anders Pettersson / Getty

A doctor views an X-ray of a hip replacement.

Calm as the horizon, lying flat on his stretcher with his stolid wife and 50-year-old son in chairs beside him, Nick was down. About an hour earlier he had bent over to put on his socks and his leg had collapsed. So his wife and son dragged him to the car, and here he was in my hospital.

Five weeks ago, the stocky old Greek, whose exuberant presence now filled his curtained-off corner of the ER, had undergone a "new old" hip replacement. Nick's artificial hip had a metal-on-metal bearing (basically a large metal ball in a metal cup) — a remake of an old design, one that doctors were using 40 years ago. In the 1970s, the metal-on-metal construction was abandoned by orthopedists worldwide because it wasn't very stable and failed to relieve pain as reliably as the current metal-on-plastic standard, a metal stem and ball in a plastic cup, which has cured so many millions of their hip arthritis. But about four years ago, the metal-on-metal design was re-introduced in the U.S. with some small structural modifications. Manufacturers are now hyping and marketing it hard to orthopedists — and to the lay public, even harder. The marketers say the new generation metal-on-metal hips should be longer lasting, tougher and most importantly, almost impossible to dislocate.

Well, here was one significant counterclaim lying on the stretcher today. Nick's shortened, turned-in leg announced the problem even before I saw his x-ray. His new old hip was dislocated.

I was interested in seeing this patient because I'd never done one of the new hips. My teacher had done them in the old days, thousands of them, but he abandoned them immediately and completely when the first metal-on-plastic hips came out. "It would be foolish to go back" is what he'd said 20 years ago when I asked him about the old designs — I took his word for it and, so far, have never regretted it. I also knew from my own experience, having done more than 1,000 hip surgeries by that point, that the metal-on-plastic kind worked — well. But my teacher has long since passed away and many of my patients have now seen the advertising and want the new metal-on-metal hip. The president of my hospital wants it too — he asked me about it just weeks ago. He thinks the "cutting edge" thing would be good for the hospital's bottom line. Even my practice partner, who has personally implanted (and witnessed the early failures of) the old metal hip has started pushing me to do it, wondering if we might be losing patients, losing our reputation, by refusing.

Nick was about as nice as an old man with a dislocated hip can be. Despite what is typically an extremely painful problem, he was pleasant, talkative and charming. His interests lay in the history of his native Sparta and in the making, extolling and drinking of large amounts of the well-known (and in my limited experience, best-avoided) pine-resin-laced traditional Greek wine retsina. Trained by decades of exposure to the resinous brew, Nick's brain and liver now presented us with an unusual difficulty: they had become so good at detoxifying his system that it was nearly impossible to sedate him.

Putting a dislocated hip back in place, or "reducing the hip" in our jargon, requires a sedated patient. It is unquestionably the most athletically challenging of all medical procedures. Two people hold the patient down, the orthopedist climbs up on the stretcher, bends the knee, picks up the thigh and then uses a combination of delicate manipulation and great brute force to pop the hip back. My back always hurts for a week after I do one. Spasms of the huge muscles around the patient's hip must be controlled with intravenous sedation — or else the entire procedure has to be done in the operating room under general anesthesia. But taking Nick to the OR would involve a long wait (in pain), tests, risks from the drugs, paperwork and high costs — all of which I wanted to avoid.

So, we kept pushing in drugs. I asked him repeatedly, "Do you feel sleepy, Nick, or a little drunk, or anything?" And he just kept smiling, saying no and talking about wine recipes and the exploits of Leonidas. Sedating old people is a dangerous business — they can stop breathing in an instant — so by the time we had given him enough narcotic to drop a horse and he wasn't even sleepy, we knew we couldn't give him any more. We had to reduce the hip with Nick fully awake.

I climbed up on the stretcher and looked straight down at him. He was perfectly alert, maybe a little amused at the sight of this doctor standing over him on his bed. I told him I needed him to relax his muscles. And, then, a wonderful light came on in his eyes. He told me he understood this — maybe it was something a wounded Spartan hoplite might have done while being treated on the battlefield. Anyway, he got it. And, by Zeus, he relaxed. So I pulled, lifting Nick and an ER doc off the stretcher, and while Nick waxed on about sterilizing old wine bottles, I felt his new old hip pop back into place. The leg came out to length and was straight again. Everyone was relieved — everyone but Nick, who seemed a little annoyed that I was leaving to order another x-ray. He was just getting to the important part about the yeast.

A big question in medicine this days is, when do we abandon a procedure we know works really well in favor of a new one that may work better? Medicine 2.0 often involves incremental improvement of things we're already pretty good at — making things safer or faster, more reliable and, yes, more attractive to patients. That last one, called "patient acceptance" by the industry, is a huge factor in our for-profit, marketing-driven world. But should patients, even really bright patients, who read every word on the Internet about their afflictions, be driving such choices?

In orthopedics, at least, the answer is "no." Only the surgeons actually performing joint replacements can make intelligent decisions as to which procedure is best. We study the engineering, the metallurgy, the tribology (friction science) — and the body's responses to these things from the gross anatomic level down to the subcellular, ultramicroscopic scale. We digest hundreds of studies about the clinical science and spend hundreds of hours in conferences hashing over the pros and cons. Then we do the operations and we live with the results for the rest of our lives; they are the swords by which we live or die. So, should a two-minute TV commercial or a random website that sways the patient sway the orthopedic surgeon too? The answer is obvious — and it was embodied in my patient. Old Nick's confidence in his wine-drinking, Persian-stopping heritage told me it would be wise to have a little more confidence in our own.

Dr. Scott Haig is an Assistant Clinical Professor of Orthopedic Surgery at Columbia University College of Physicians and Surgeons. He has a private practice in the New York City area.