Squeaky artificial hips baffle surgeons

-Bucks County Courier Times

05/25/2008- A constant creaking like a loose floorboard isn’t a sound Dr. Andy Star anticipates hearing when people enter his examination room.

So the first time he saw a patient with a squeaky artificial hip, he was left dumbfounded. “As a surgeon, hearing someone walk, hearing them squeak, it’s a little unsettling,” said Star, chief of orthopedics at Abington Memorial Hospital. “We are a little anxious about it and we honestly don’t know what to tell the patients.” Short of a second major surgery, there appears to be almost no options for dealing with this mysterious and annoying phenomenon, one that doctors are reporting among some people with ceramic hip replacements. As recently as 2006, the American Association of Orthopedic Surgeons called the hip squeaking an underreported medical trend that has stumped the medical community. Roughly 235,000 total hip replacements were performed in 2005, according to the American Academy of Orthopaedic Surgeons. Surgeons substitute deteriorated hip joints with plastic, metal and ceramic materials that can be used together or in different combinations. So far, no medical evidence suggests the noise is a precursor for structural problems with the implants, according to studies. Generally, patients report no pain or other physical problems with the implants, aside from the noise when they move. Reports of noisy joints following hip replacements were extremely rare before 2003, when the federal Food and Drug Administration approved the first ceramic-on-ceramic implant for total hip replacements, according to medical professionals.Ceramic has been used in joint replacement surgery since the 1970s, and modern medical grade ceramic is harder and scratch-resistant, which lab tests suggest produces less wear and tear and lasts longer. The durability factor is why total ceramic hips are popular among younger, more active patients, doctors said. The noise reports are apparently almost exclusively found in patients with both ceramic ball and socket combinations. A 2006 study in the Journal of Arthroplasty found that 10 out of 143 patients, or 7 percent, who had total ceramic hip replacement from 2003 to 2005 developed squeaking when walking, bending, even during sexual activity. Another 31 patients reported their new hips made other noises, such as popping and grinding. No squeaks were reported among 48 patients who received hips made of metal and plastic. Local doctors added they’ve heard of no reports of noises among patients with ceramic and plastic or metal combination implants. No sound answerOther similar ceramic studies have produced a range of results. The Rothman Institute, a major orthopedics group in Philadelphia, reported it recently reviewed about 1,500 of its patients with ceramic hips and found the squeaking condition occurred in 49 cases, or about 3 percent. Another study found patients with total ceramic hip replacements reported that squeaking started an average of 14 months after surgery. Patients with squeaking hips also tended to be younger, heavier and taller than patients with silent ceramic hips.The source of the squeaking has eluded the medical community, though theories abound, including decreased lubrication in the joint, mismatch of implant parts and extreme flexing of the implants.

Stryker Orthopaedics-manufactured Trident implants reportedly account for the majority of complaints, according to reports. Last year, the Food and Drug Administration issued a warning to Stryker for manufacturing and quality problems with its ceramic hips, including squeaking.

But the company maintains its product is safe and the FDA warning and a subsequent recall involving ceramic hip parts made at an Ireland plant were not related to squeaking, which it says occurs with less than 1 percent of its ceramic implants. Doctors who’ve removed the ceramic implants have found evidence of accelerated wear, but durability tests suggest no signs of pending joint failure and suggest that the ceramic would have outlasted metal and plastic implants.As far as quieting the noise, one study suggested that squeaking that happens when patients bend forward could be managed with different bending techniques. But for squeaky walkers, it appears a second surgery is the only option.Old vs. newOver the last 18 months, some area orthopedists have seen a handful of patients with squeaky hips looking for second opinions.Surgeon Dr. Charles Burrows has seen three such patients in the last six months at his practice, which is associated with Doylestown Hospital. None complained about pain. None appeared to have any implant deterioration. Also, none of the patients opted for a second surgery to replace the ceramic, the only known long-term noise solution, he said.Burrows, a knee and hip replacement specialist, said he doesn’t use ceramic in hip patients. He stopped using ceramic balls six years ago, though his biggest concern was safety, not squeaking. Ceramic is brittle and, if it breaks, removing all the shards is almost impossible and increases the risk of infection, wear and other complications. Generally speaking, noise complaints are “extremely rare” among hip replacement patients, said Star, Abington’s orthopedics chief. He has seen a half-dozen patients with squeaking hips looking for second opinions. Recently, he saw his first noise complaint from a total metal hip replacement patient.None of his patients who’ve had total ceramic hip replacement have complained about noise, though it’s not a combination he uses often. With younger active patients, Star prefers total metal hip implants. But metal-on-metal devices also shed tiny ionized metal particles that some worry may increase cancer risk. To mitigate that risk, Star uses the ceramic-on-ceramic implants only for women in child-bearing years.That is part of the quandary with joint replacement surgery: deciding between conventional methods and new breakthroughs, Star added. Plastics and metal have proven success records; surgeons know how they work, the advantage and disadvantages. With newer materials and combinations, though, doctors rely on performance data based on lab testing.St. Mary Medical Center orthopedic surgeon Dr. George Cautilli hasn’t seen patients with squeaky hips, but he also uses ceramic materials sparingly. While the material is a promising technology, Cautilli says ceramic hip implants haven’t been around long enough to satisfy him. He prefers sticking with what he knows works.

“Unfortunately, theory and practice are two different things,” Cautilli added. “Now I’m so glad I didn’t make the jump.”

 

If you or a loved one have experienced any of the symptoms listed above you may be entitled to compensation. Contact the Stryker Hip Implant attorneys of Ennis & Ennis today for a free confidential case evaluation. Our on staff nurse and lawyers are standing by to answer any questions you may have regarding the Stryker Hip Implants, a possible Stryker class action lawsuit, or any other type of Stryker litigation.