Thirty-two-year-old Joe walked up the aisle of the church alongside his new bride, looking forward to a full day of taking pictures and dancing at his reception late into the evening. This wouldn't be an unusual expectation for a young groom on his wedding day, except that a few months earlier, Joe could barely stand up and walk a few steps, much less dance. A total hip replacement (THR) surgery is what made the difference in his life.

Joe was shocked to hear his doctor recommend THR surgery. It never occurred to him that he could be old enough to have the sort of problems that required a hip replacement.

"Because I didn't anticipate any kind of joint pain, I thought [the pain] was a pulled muscle, a pinched nerve, but joint pain wasn't what I expected."

The diagnosis was avascular necrosis, and because the condition had deteriorated so rapidly, immediate surgery was recommended.

"Hip replacement surgery is for people in their 60s and 70s, not for someone as young me," Joe quipped.

His feelings were quite the opposite within weeks after the surgery when he realized his pain had vanished, allowing him to get back to the life he led before the problems began.

"It's like night and day. The pain is completely gone."

About 10 years ago, the outcome of Joe's story may not have been so optimistic. It's only been within the past few years that the philosophy regarding THR surgery and the young patient has evolved. Advances in medicine and technology have come together to make this type of surgery a more promising solution.

Historically, THR surgery was performed mostly on people age 65 and older. This was for three reasons. Fixation of the implant to the bone in younger people had been unpredictable in the past. Implants used in replacement surgeries had the potential to wear and break with too much stress. Finally, recovery and rehabilitation time often took several months, requiring a younger patient to take disability from work and put their social lives on hold.

The good news is that recent advancements in the areas of implant designs have given longevity to the prosthetics now used in surgical procedures. This, combined with new surgeries that use minimally invasive cutting techniques, has greatly improved THR surgical results, as well as recovery and rehabilitation time from what they were in the past. But as it is with anything new in science, the new surgeries have supporters, as well as critics.

Evolving Technology

Recent developments in the quality of implants used when replacing a patient's hip joint is a major factor in allowing the surgery to be performed successfully on younger people. Technological advances in the design of the prosthetic, including material used, is crucial to the overall advancement of the THR procedure.

"In a hip replacement procedure, doctors replace diseased hips with implants made of metal or medical grade plastic," says Monika Gibson, spokesperson at Warsaw, Ind.-based DePuy Orthopaedics Inc., which designs and manufactures orthopedic devices used in hip replacements.

Improvements in the design of the implant have increased the longevity of the joint, allowing the recipient to extend the amount of time between revisions. Andrew Star, MD, a hip and knee specialist at the Orthopedic Specialty Center in Willow Grove, Pa., uses a specialized metal implant with the minimally invasive surgery.

"Hip implants have a spherical head that replaces the diseased ball of the hip joint," Star explains. "The S-Rom Hip implant has a larger head -- about 30 percent larger than the head on a standard implant -- and it's made of metal on both sides of the joint. The larger head spreads stress over a larger surface, potentially reducing wear and tear on the implant." Implants are now more durable and able to withstand the activity and movements of the average young adult.

In addition to the improvements to the implant materials, there have also been advancements in fixation -- implant fixation to the bone. The evolution of this process has had one of the biggest impacts on the change in philosophy by many surgeons to perform THR surgery on younger patients. The issue of whether to cement the implant to the hip, often a permanent choice for older patients who are unlikely to require a revision surgery, versus uncemented bonding, which has traditionally been the choice for younger patients who will likely require a revision within the next 15 to 20 years.

"We've learned a lot over the last 20 years," says Bryan Nestor, MD, assistant attending orthopedic surgeon, Hospital for Special Surgery, Weill Medical College of Cornell University, N.Y. "We've learned a lot about what works and what doesn't work. I would say, with regard to fixation, that issue has advanced considerably."

With improvements in both implant design and fixation predictability, even young patients have a reasonable expectation of 15 to 20 years before revision, depending on wear, which is a major factor in the implant's durability. But research is ongoing to discover ways to go beyond the 20-year mark.

The goal is to "maybe increase that number to go 20 years plus, making the hip replacement in a young patient to be their last operation," says Nestor. "There are possibly going to be some issues where maybe we reduce wear, but what are the other issues? That's the area of investigation. The hope would be by reducing the wear, which really seems to be the problem that limits long term durability, that we might extend the life span of these implants."

New Surgery Techniques

While upgrades in the design of the implant and fixation have expanded the time period in between replacement surgeries, new surgical techniques have made the patient's recovery and rehabilitation time easier to endure. The surgeries -- one-incision and a two-incision approach -- are techniques used where one or two small incisions of 1-4 inches in length can be made to allow adequate exposure of the joint.

According to the American Academy of Orthopaedic Surgeons, the type of total hip arthroplasty (THA) performed and the number and size of incisions used are key factors in determining how fast a patient is able to return to normal activities post-surgery. In contrast, surgeons performing the traditional surgery create an 8- to 12-inch incision in the upper thigh, cutting through muscles and bones to insert the prosthesis. Patient hospital stays are typically up to eight days, followed by a four-month rehabilitation and recovery period.

However, there are generally less complications with the direct traditional open approach. It is upon the susceptibility to complications for each type of surgery where surgeons disagree about which type of procedure is best.

In the one-incision minimally invasive surgery (MIS), the surgeon performs the same type of surgery as the traditional procedure, but the incision is smaller. With the smaller, four-inch incision, there is less muscle and bone cut, therefore, less pain and less rehabilitation required.

"In minimally invasive surgery, surgeons are using the same procedures as open surgery," says Thomas P. Sculco, MD, surgeon-in-chief, Hospital for Special Surgery and chairman and professor of orthopedic surgery at Weill Medical College of Cornell University, N.Y. "I started doing minimally invasive surgery seven years ago. Now, some 2,000 cases later, the safety and efficacy of the procedure has been proven. By using the single-incision approach, you retain the success of the traditional hip replacement with the benefits of a smaller incision," says Sculco.

The most recent approach is the two-incision less minimally invasive surgery (L/MIS), which utilizes one small incision to insert the acetabular component (hip socket), and then a second small incision to insert the femoral (thigh) component. Having two incisions, one in the front, the other in the back, allows the surgeon to navigate the implants around the muscle and bone. Because muscle and bone are left intact during this procedure, patient pain is minimal, hospital stay is usually shorter and recovery time is cut in half.

"Because the surgical dissection underneath the skin avoids severing muscles, two-incision hip replacement patients begin functioning and walking earlier than patients who undergo standard surgery with a four-inch incision, and those who undergo traditional open surgery," says B. Sonny Bal, MD, assistant professor, department of orthopedic surgery, University of Missouri School of Medicine, Columbia, Mo. "The size of the skin incision is really irrelevant to patient recovery, as long as muscles are not detached or severed," says Bal.

The use of fluoroscopic imaging is used on occasion when visualization of the joint is impaired during the surgery and when there is doubt about the placement of the implants, according to Bal. There is a higher learning curve for the two-incision approach than for the other surgeries, which is a disadvantage of this surgical technique and a suggested reason for the development of complications when surgeons are beginning to use the technique.

Because the two-incision surgery is relatively new, there are still differences of opinion as to how safe it is, as well as how much higher the risk of complication is. Sculco believes that the inability to have a clear view of the femoral position, relying on fluoroscopy for guidance, is an invitation to complications.

"All surgeons learn the same basic technique, in which they can actually view the joint through the incision site. If a surgeon only performs 10 to 15 hip surgeries per year, he or she needs to be able to see the operation site; errors due to lack of visualization can result in complications, such as fracturing the femur," says Sculco.

In his support for the two-incision approach, Bal explains, "We use the two-incision technique for all routine, uncomplicated hip replacements at this time, with early outcomes that are better than anything in our prior experience. The technique appears to be safe and predictable as long as the incision size is made as large as necessary for adequate surgical exposure."

Each of these new developments in science and medicine for THR surgery is good news to the 33 percent of Americans who suffer daily from arthritis and chronic joint pain. In fact, recent data from the Centers for Disease Control and Prevention (CDC) suggest that in Pennsylvania, this number jumps to almost 40 percent of the adult population that are afflicted with those problems. These are people like Joe, who thanks to the new developments in total hip replacement surgery, could not only look forward to the start of a new life on his wedding day, but the beginning of a pain-free life as well.  

Mary Kelly is a freelance writer based in suburban Philadelphia.