It’s All in the Hips
With steady improvements in surgery and implants, this ball-and-socket joint just keeps getting better.
As an adult reconstructive surgeon with a specialty in hip replacement and hip preservation, Dr. James Guyton has seen many advancements during his 22 years at Campbell Clinic Orthopaedics. Indeed the whole field of hip treatment has experienced dramatic change over the last half century.
Decades ago, a broken hip could spell calamity. Bedridden patients, waiting for the hip to heal, often developed pneumonia and never recovered. “[Doctors] didn’t appreciate how you had to mobilize the patient quickly,” says Guyton, “and surgery was primitive.” Then, in the 1960s, total hip replacement was pioneered by Sir John Charnley of Great Britain. By the 1980s, it became “standard procedure as far as how the hip is repaired after a fracture,” says Guyton. “Since then, devices keep improving.”
While he treats patients after they break a hip, the majority come to him because their hip is wearing out. “And honestly,” he explains, “hips usually wear out because of a pre-existing condition since childhood that leads to arthritis. Probably 85 percent of these patients had some childhood deformity they didn’t know about. That knowledge has only come to be appreciated in the last decade or so, and it’s put a big thrust on catching deformities earlier so we can do hip preservation.”
One of the most common deformities is hip dysplasia, which occurs when the socket is too shallow. “I cut it free and rotate it to where it covers the top of the joint’s ball,” says Guyton, who performs about 10 of these procedures a year. Another common deformity that can be treated by hip preservation is hip impingement, which occurs when the socket is too deep so that the neck of the femur hits the socket, causing the joint to wear out.
As for replacing the hip joint — which can be partial or total — the chief indication is “pain that is altering the person’s life in such a way that they’re willing to take the risk of surgery,” says Guyton. “All patients have different thresholds. Some come at the first whiff of pain; others wait till they’re dragging their leg around. Some very stoic people will go on till the bone starts wearing away. But we don’t operate till we’re really sure we can help the patient. We determine that by x-rays. An MRI can show early changes of arthritis, and we use them with hip preservation to see cartilage. But with hip replacement, x-rays show enough.”
Prior to surgery, doctors often meet with family members who will care for the patient. “I always like to meet the ‘support personnel’ so they all know what to expect. If I perform surgery on a patient who has no one to help them, then they’ll need to go to a rehab center for a while. It’s really better at home with someone to care for them.”
As far as the type of hip replacement performed, Guyton says with a fracture, a partial replacement is usually appropriate because the cartilage on the socket is still good. But with an arthritic hip that isn’t fractured, he performs a full replacement. “We pop the ball out of the socket, and cut the ball off the end of the femur, or thigh bone. Then we pull that out of the way and clean out old cartilage. The new metal socket, which has a plastic liner, is driven up into the bone socket, and it becomes the new socket on the pelvis.”
On the thigh bone, he prepares the internal cavity to the shape of the implant he’ll insert. “It has a tapered shape, and the body grows into these devices. The backside is made of porous metal, and your body loves to grow into titanium porous metal.” Crediting dentists for first using these metal implants, Guyton adds, “They’ve gone through modifications [on hips] but they now work well.” Finally the new ball is put in place and muscle tension holds it together.
After a hospital stay of usually two days or less, patients are sent home, where preferably family members can help them for at least the first week. They’ll use a walker for two weeks after surgery, receive outpatient physical therapy, and gradually ease back into other activities. “We used to restrict people in a big way,” says Guyton, “but now we tell them not to run and jump on [their new hips]. Golf is fine, and so is tennis, in moderation. But we don’t advise taking up running as a hobby after hip replacement.”
Deciding when to return to work depends on the person and his employment. “Some are back in two to three weeks or even sooner. But those with very vigorous jobs, like a fireman who has to climb a ladder, should probably wait two to three months.”
Helping the patient recover more quickly today is better pain control. “If we can keep pain from getting started before the surgery, the patient’s experience is much better,” says Guyton. “In other words, we don’t delay the pain, we avoid it altogether.”
Also helping to reduce pain are minimally invasive surgery techniques, which inflict less injury to the body. “We tried some really small incisions, going from eight inches to two-and-a-half inches,” says Guyton. “I think we went backwards with that. Yes, it was less invasive, but there’s a real premium in being able to see what you’re doing. Now the incisions are three-and-a-half inches. I think that’s the smallest surgery we can perform and still do a good job.”
Also being tried are different surgical approaches to hip replacement, among them the anterior approach, which involves cutting through the front of the hip area instead of the buttock. Proponents cite several advantages, including reducing the chance of the ball popping out of the socket, and shorter recovery time. “I’m not doing that approach,” says Guyton. “I’m waiting to see if it truly has an advantage in the long term.” He also points to a downside — the risk of complication, “particularly getting a fracture of the bone while surgeons are putting in the device.”
Other risks also come with hip surgery. “With a hip fracture, your chance of dying within the next year is 10 to 20 percent,” says Guyton. “You face the risk of infection and blood clots. A lot of people who break their hips are becoming frail anyway, so it’s a marker of people declining.” But, he adds, those who survive the first year after hip surgery after a fracture go back to age-adjusted mortality rate.
Patients who have total hip replacement are at risk for complications because it’s a bigger operation than a partial replacement,” says Guyton. Pneumonia can also set in, though use of the spirometer — which strengthens the patient’s lungs in the hospital and during recovery — has helped reduce that development.
Even with risks, which occur with any surgery, the field of hip replacement continues to advance. For instance, not long ago the rate of balls popping out of their sockets was 2 to 3 percent. “Now with better repairs of the connections between the pelvis and the femur,” says Guyton, “that’s down to a very small percentage.” Also in the past decade the plastic in artificial hips has improved. “One reason the parts came away from the bone was because the body reacted to plastic debris by loosening the metal parts,” says Guyton. “That debris made a little membrane that worked its way between the bone and the metal to loosen it, and in some cases formed cysts on the bone. With improvements made in 2001 we’ve seen very little of that.” Also, after the recall of certain hip implants a few years ago, researchers and surgeons learned that metal balls in metal sockets didn’t work well together. Now the balls are made of fracture-resistant ceramic or ceramicized metal.
Asked if he’s ever had to repair or re-do a replacement, Guyton responds, “Yes, sometimes that happens. How we correct it depends on how the person has broken it. And starting over can be very hard. It’s not like changing out brake pads.”
However, “unless you fall off a ladder or something,” he adds, a good hip replacement holds up for decades. “Not long ago they could last 10 years. Now they last 20 years. We’ve come a long way, and I think we’ll keep seeing very good results.”