What is Hip?

When Robert Cairo was a 19-year-old linebacker at the University of Delaware in the late 1970s, he noticed that he was experiencing more post-scrimmage soreness than his teammates. The pain radiated down his legs, sometimes for days. No one knew why. Determined to find a cause, he traveled to the Hospital for Special Surgery in New York City. There he learned that congenital deformities were causing his hips to wear out. The doctor told him to cope as best he could and sent him home.
Cairo returned to the gridiron, playing well enough to earn a spot on the 1979 National Championship team. But the pain increased, until it eventually claimed his ability to participate in every sport he loved. Things got so bad, even routine activities like sleeping and climbing stairs became torture. The only way he could work as a physical therapist was to sit on a stool and wheel himself to the patients.
So in December, at age 49, Cairo opted for double hip replacement surgery. And though he realizes that his days as a competitive athlete are behind him, he can now bicycle, row, lift weights and live life without pain.
Once reserved for the elderly, surgery to replace damaged knees and hips has become so common among active baby boomers that it almost seems like a badge of honor. Most joint replacements are the result of osteoarthritis, which wears down the joints, limiting mobility and causing debilitating pain. Congenital conditions, obesity and injury or trauma can contribute to arthritis in younger people. Orthopaedists say they are seeing athletes in their 40s and 50s whose activities may have accelerated their arthritis.
An analysis done at Florida International University found the number of joint replacement surgeries among patients between 45 and 64 increased 71 percent for hip implants and 83 percent for knee implants in 2004.
It’s not surprising that so many people are opting for joint replacements. Artificial implants have spared millions the fate of spending their latter years confined to a wheelchair. Indeed, joint replacement is one of the most reliable surgical procedures. The American Academy of Orthopaedic Surgeons reports that the surgeries are successful in more than nine out of every 10 patients and that, when complications do occur, most are treated successfully.
Prostheses that used to last 10 to 15 years can now last 25 to 30 years, though long-term data on their performance are not available. Modern materials and designs have improved on earlier versions. Though more expensive, these implants are better-suited to young, active patients, says Dr. Wilson C. Choy of Orthopaedic Associates of Southern Delaware in Lewes.
The downside: metal debris from wear can become ionized and travel throughout the body, leading to elevated levels of metal in a patient’s blood and urine. For this reason, some types of implants are not recommended for people with poor kidney function or women of child-bearing age.
Metal-on-plastic prostheses are now made of a more durable plastic, greatly reducing wear. “Metal-on-plastic is still the gold standard in hip and knee replacement,” says Dr. Steven M. Dellose, of Delaware Orthopaedic Center in Wilmington.
Ceramic-on-ceramic implants got a lot of press when golfer Jack Nicklaus underwent hip-replacement surgery in 1998. But surgeons note that while durable, ceramic is brittle and can shatter.
Surgical techniques are also improving. One of the biggest changes has been computer modeling to help surgeons measure their cuts and choose the best implant size for the patient, Choy says.
In addition, most implants are being done without cement. Instead, bone is allowed to grow around the stem of the prosthesis to hold it in place, making it more secure and extending its lifespan.
Time has also been shaved off the procedure. “Depending upon the surgeon, it can take only 40 to 45 minutes,” Dellose says. Recovery time has improved, too. Patients used to remain in the hospital for up to 10 days. Thanks to smaller incisions and aggressive rehabilitation, that time has been whittled to three days.
“Improved materials and techniques have made us more comfortable doing the surgery on younger people,” Choy says.
But young people often have high expectations about what they can accomplish with their new parts. Surgeons emphasize that, while durable, implants cannot tolerate as much stress as a native joint. Therefore, high-impact activities such as running and contact sports that risk trauma are best avoided.
“We’re not turning back the hands of time,” says Dr. Alex B. Bodenstab, of First State Orthopaedics in Newark. “We’re not returning a hip or knee to like when you were 20 years old. It’s not going to function that way.”
Cairo agrees. He’s content to be able to resume low-impact sports and has no intention of returning to running or racquetball. “I’ve had my day in the sun,” says Cairo, now 50, of Rehoboth Beach. “Now I just want to keep my hips.”
Likewise, Emma Fulton, 66, of Dover is happy to be able to accompany her friends on a shopping trip. But Fulton, a two-time cancer survivor who had both knees replaced because of injury and osteoarthritis, has one more goal: to ride her motorcycle across the country to support the battle against colorectal cancer. “Once a biker, always a biker,” she says.
Joints are covered by a thin layer of cartilage that cushions the blow of every step. Only a few millimeters thick, cartilage wears away over time, but increased activity can accelerate the process. When the joint loses cartilage entirely, it develops osteoarthritis, which affects 27 million Americans.
Injury can also prevent a joint from functioning properly. Even a bad sprain, if left untreated, can predispose someone to arthritis, Choy says. Obesity also stresses joints, especially the knees.
A total of 5,757 knee replacements and 3,858 hip replacements were performed in Delaware from 2001 to 2004, according to the Delaware Hospital Discharge Report. As with the national trend, more young people are joining the ranks.
“Fifty percent of my patients are under 65, and those numbers are likely to increase,” Bodenstab says. Says Choy, “It’s a quality-of-life issue.”
For Roger Roy, 67, of Hockessin, having new knees means being able to spend a day on the ski slopes without pain. Roy, who underwent 13 previous surgeries because of athletic injuries, got new knees last year. He says he feels 10 years younger. He’s back to a full schedule of bicycling and skiing.
But the younger a patient is when he undergoes primary joint replacement surgery, the more likely he will need a “do-over” procedure in the future. “If you have an artificial joint, it’s a matter of the number of cycles it can do,” says Dr. Nelson Wiegman, of New Choice Orthopedics in Milford.
Revisions are needed when an implant fails due to infection, wear or injury. Revisions are harder to perform than primary joint replacements, and each additional surgery carries the risk of infection. “They take a lot of work, and the quality of your results is 10 percent to 15 percent below what it is for primaries,” Wiegman says.
The hope is for a biological solution that would reduce the need for joint replacement. So far, experiments with cartilage implants have been less than encouraging, and gene therapy is years away, Dellose says.
So what can you do to avoid becoming part of the joint replacement epidemic?
“The most important thing is to keep your weight down,” Dellose says.
The bottom line: Try to keep your native joints as long as you can.
“Nothing is as good as what God gave you,” Dellose says.