Australian Experts Advise Hip Replacement Patients

ImageAccording to a recent article dated September 30, 2012 published on an Australian news Web site, metal-on-metal hip replacement recipients to have their devices checked regularly.
 
The NineMSN.com.au further defined the ways for check-up, namely, ultrasound, MRI, and blood tests, as suggested by Australia’s Therapeutic Goods Administration (TGA).
 
The Australian article further cited the new study conducted by the U.K.’s National Joint Registry.
 
It discussed about all-metal hip replacement recipients who do not have an increased risk for developing cancer in the first seven years after undergoing a hip replacement surgery.
This is in contrary to previous reports saying that there might be a higher risk due to metallosis or metal toxicity.
 

Osteonecrosis May Result in Hip Replacement

One of the major reasons of sudden hip pain is hip fracture. As people grow old, the possibility of getting a fractured hip increases. This is because falls are more likely and bones become thinner, according to medical observers. Meanwhile, osteoporosis sufferers can get a fracture from simple, daily activities, not just from a big fall or injury. Death of the bone or osteonecrosis is also one of the major causes of hip pain leading to a need for hip replacement surgery. Other causes of hip pain include tendinitis, strain, sciatica, bursitis, arthritis and infection. Hip replacement surgery is one of the most risky treatments of hip pain. A recent study connects metal-on-metal hip prosthesis and ‘nanoparticle’ release in human tissues.

Osteonecrosis is a kind of bone disease that is commonly associated with large joints like the hips, knees, ankles or shoulders. Also known as bone necrosis, this disease leads to disfiguring and weakening pain. This is a rather rare disease diagnosed in approximately one in 20,000 people every year.

Osteonecrosis further results in a permanent loss of blood supply to the bone, resulting in the death of bone tissue and total collapse of bones. Approximately there 10,000 to 20,000 new cases of osteonecrosis each year in the United States. Most of these cases occur as a result of bone injury, like a fracture or dislocation. Symptoms of osteonecrosis of the jaw may include restricted pain in the jaw area, numbness, loosening of teeth, soft tissue infections, and bone exposure within the oral cavity.

Due to these hip pain problems, many people opt for hip replacement surgery. Hip replacement surgery refers to the procedure in which the injured part of the hip is removed and eventually changed with a new device. The procedure’s prognosis is good; however, it is startling that there might be problems caused by faulty devices. The allegations on DePuy Orthopaedics Inc. metal-on-metal products serve as an example. According to medical studies, fewer than 50% of people with a hip fracture return to their former level of activity. Thus, hip problem may change the quality of life significantly.

There are around 93,000 recipients of the ASR XL Acetabular System and the ASR Hip Resurfacing System worldwide. After the release of data presenting defectiveness in one out of eight patients to whom they were implanted, the two devices were pulled back. The global DePuy hip recall was made known to the public in August 2010. After the recall, the number of affected patients filing hip replacement lawsuit increased.

References:
• nlm.nih.gov/medlineplus/osteonecrosis.html
• niams.nih.gov/health_info/osteonecrosis/
• rheumatology.org/practice/clinical/patients/diseases_and_conditions/osteonecrosis.asp

What’s in a Hip Prosthesis

A damaged hip joint causing pain and functional impairment is generally managed by hip replacement surgery, medical journals say. A hip implant will be positioned in place of the damaged joint. These implants are available in different designs and are manufactured by various device makers. An example of a hip device is the recalled hip replacement system of DePuy Orthoapaedics. The U.S. Food and Drug Administration (FDA) sent DePuy a letter informing it that the government would not approve the ASR XL Acetabular System for use in the United States, even though DePuy sold the device overseas. The FDA recently disclosed that between 2000 and 2011, hip replacement adverse event reports grew to 16,800.

The hip joint is a ball-and-socket part in which the spherical head of the thighbone moves inside the cup-shaped hollow socket of the pelvis. The materials used in the implant depend on several factors, including the age of the patient, the patient’s level of activity and the surgeon’s preference. If you are considering to have a hip replacement surgery, you may ask your doctor what type of hip replacement prostheses is suitable for your condition.

In the procedure, a lining on the concave part of the hip socket is fitted with the part of the hip prostheses called the acetabular cup. The acetabular cup is fitted in its right place with the use of cement or through friction application.

The component of a hip implant fitted to replace a damaged femur is called the femoral component. The femoral component is then held on its rightful place with cement such as acrylic bone cement or through non-cemented method such through friction, its shape and through a special type of coating that allows bone growth around the device.

The part that is located in the middle of the femoral component and the acetabular cup is called the articular interface. It is actually a simply-designed ball-and-socket joint that mimics the original one. The interface size may vary in  sizes such as 28 mm, 32 mm and 36 mm and this is measured by determining the diameter of either the femoral head or that of the acetabular socket.

It has also been stated in some reports showing that those who experienced premature complications due to the hip replacement device tend to have smaller hip cups. Knowing what type of hip device you are using is crucial. Those who experienced complications from defective DePuy artificial hip implant may check out updates of the recall and learn about the possible steps in filing a DePuy hip replacement lawsuit with the help of an experienced and efficient lawyer if they feel that they are legible to file their respective cases.

References:

  • orthoinfo.aaos.org/topic.cfm?topic=A00355
  • arthritis.org/types-replacement-parts.php
  • livestrong.com/article/90144-components-hip-replacement/

Metallosis and DePuy Hip Replacement Sytsems

Medical regulators have recently begun to investigate the DePuy ASR hip replacement system and its unique metal-on-metal (MoM) design due to several reports.The biggest concern of these medical regulators is that, as the hip replacement wear down, metal particles may be released from the artificial hip and interact with the soft tissue such as muscle and ligaments surrounding the joint and enter the bloodstream. This reaction by the metal particles would then cause a rare blood disease called Metallosis.

Some of the symptoms of Metallosis have been known to include: inflammation, infection, immobility, joint stiffness, lack of range of motion, tinnitus, vertigo, blindness, deafness, peripheral neuropathy, headaches, optic nerve atrophy, convulsions, cardiomyopathy, hypothyroidism, osteolysis, pseudotumors, skin rash, necrosis, and even loosening of a metal orthopedic implant. Specialized blood tests may be used to detect levels of toxic metals in patients experiencing these symptoms. In some cases, patients with DePuy implants have been found with 100 times the normal levels chromium and cobalt in their bodies. High amount of cobalt in the body, commonly known as cobaltism, can actually cause harm to the body’s organs.

Normally metallosis is a rare condition for those who have received a replacement system for their joints, although hip replacement users have been known to be the most prone. Several reports have shown that the DePuy ASR is more prone to cause debris problems.Unfortunately for those patients who have begun to suffer from Metallosis the only cure is revision surgery.This means that the hip replacement would have to be changed or removed altogether. This would also extend the rehab time of the patient while causing him or her more pain.

Reports of Metallosis caused by the DePuy ASR hip replacement have caused several more lawsuits to be filed against DePuy. Records show that the first of these lawsuits in the United States alone was filed in March 2009, a mere 18 months after the DePuy ASR was recalled. Also the United States Food and Drug Administration (FDA) has received over 500 complaints about the DePuy ASR and the metal-on-metal wear down before March 2009.

URL References:
drugsideeffects-info.com/drug-side-effects/musculoskeletal/metallosis/