Total hip replacement is an increasingly popular procedure in the US. The reason is probably in the huge number of baby boomers getting old and getting their hips busted. According to the CDC , in 2009, there were 327,000 total hip replacement surgeries. About 400,000 hip replacements is a yearly average. Women seem to be more inclined to get their hips replaced, but according to the new study, they are also more likely to experience the failure of their new hips, and to need revision procedure.
The new study was conducted by the researchers from the Southern California Permanente Medical Group in San Diego. The researchers reviewed data on 35,140 replacement procedures completed at 46 US hospitals. The average age of the patients was about 66. About 57.5 percents were women.
Scientists found that the success ratio of this now common procedure is very high: 97.4 percent of all implants survived up to the five year mark used for the study. But, of those procedures that failed, women were 29 percents more likely than men to require repeat surgery during the first three years after they received the implant.
One of the goals of the study was to study sex-specific risk factors of the hip replacement, because of the important differences in the anatomy between women and men and women. Another goal was to find out which type of the device was most likely to fail.
The researchers discovered that more women than men got the smaller, 28 mm femoral heads, while more men received larger femoral heads and metal on metal-bearing devices. But, the conclusion was that the number of participants in the study was not big enough and the period of time was too short to make any conclusion about the type of the device or procedure which is considered more risky than others. As a consequence, the researches could not offer any recommendation to physicians who are making the decision about which type or model of artificial hip to use.
Hip replacement is fairly common surgical procedure to replace the hip joint by an artificial implant. The replacement can be total, with the replacement of the concave part of the pelvis and the head of the femur. Partial replacement replaces only the femoral head.
The reason for this popular surgery is to relieve pain caused by arthritis, to repair damage done by the fracture and to improve the mobility and the quality of life of patients. At this time, hip replacement is the most common of all orthopedic surgeries.
Hips can fail for many reasons. Join failure is often caused by osteoarthritis, rheumatoid arthritis, hip fractures, bone tumors, avascular necrosis, and many other issues.
There are many models and designs of artificial hips produced by various manufacturers, but the device is fairly simple and there are only three basic parts: a stem, which is inserted into the femur, a ball that is attached to the top of the thighbone, and a cup, which is attached to the pelvis.
Modern hip implants are manufactured from several materials, including ceramics, plastics and metals.
Hip replacement complications
Hip replacement is not to be taken likely, since it has risks inherent in any surgery. It should be considered only if other therapies fail.
There is a range of possible complications from the hip replacement surgery. Metal-on-metal devices can cause metallosis, a buildup of metallic particles in the soft tissue. Another serious complication is osteolysis, the loss of bone surrounding the implant. The body attempts to get rid of foreign particles created by the device during its use. Osteolysis causes loosening and finally a complete failure of the device.
Other fairly serious complications are infection, implant dislocation, ossification of soft tissue, bone death, loosening of the device, fracture and others.
Metal-on-metal hip implants are currently among the most popular because of their potential durability. But, metal ions from the device can get loose and enter patient”s bloodstream. This causes metallosis, a metal poisoning. In addition, metal-on-metal implants can also get loose, the joint can get dislocated, or the artificial hip can start squeaking.
Any of these problems require new operation to replace the hip with the new one, costly and painful remedy. It is no wonder that many people opted to sue the manufacturers of the devices they believed were faulty.
While hip replacement devices must be approved by the FDA, companies can bypass the lengthy approval process and rigorous testing by claiming that the device is similar to the previous ones which have been already approved. Three largest hip replacement manufacturers, Zimmer Holdings, DePuy Orthopaedics and Stryker Orthopaedics took advantage of the FDA ‘streamlined’ approval procedure and are now facing a range of lawsuits for faulty hip devices.
In 2011, the FDA decided to order more than 20 producers of metal-on-metal hips to do additional studies of these devices. In the meantime, an FDA panel recommended that surgeons should discontinue the use of metal-on-metal implants until the new, proper classification has been completed.
In the meantime, it is hoped that the successful outcome of the number of lawsuits against the manufacturers of faulty hip prosthetics will force them to stop sending to the market untested and unsafe devices.