Hip Resurfacing News - Metal Allergies

ASR Recall by DePuy 2010

nospam@example.com (Patricia Walter) — Fri, 03 Sep 2010 09:24:25 -0700

DePuy has announced that it is voluntarily recalling the ASR™ XL Acetabular Head System and DePuy ASR™ Hip Resurfacing System. DePuy is providing the information below to help visitors with questions and concerns. Visitors are also invited to visit the DePuy website at www.depuy.com.

DePuy makes patient safety and health a top priority and is continually evaluating data about its products. Most ASR hip replacement surgeries have been successful. However, data recently received by the company shows that more people than expected who received the ASR hip experienced pain and other symptoms that lead to a second hip replacement surgery, called a revision surgery.
For this reason, DePuy Orthopaedics is recalling its ASR™ XL Acetabular Head System and DePuy ASR™ Hip Resurfacing System. This recall means additional testing and monitoring may be necessary in hip replacement patients. In some cases, patients may need additional surgery.
DePuy is working closely with health care professionals worldwide to contact patients with ASR hip implants. Most people with ASR Hip System implants do not experience problems, but it is important that patients with ASR Hip System implants be evaluated with by a surgeon. Patients with problems reported different symptoms with their ASR hip implant, including pain, swelling, and problems walking.

DePuy intends to cover reasonable and customary costs of monitoring and treatment for services, including revision surgeries, associated with the recall of ASR.

Click here for the press release

Click here for the patient information page on our web site

Click here for an image of the ASR Hip System

Medical Release Form:

Patients with an ASR Hip are asked to complete the form and bring it with them to the appointment to give their surgeons permission to share information directly with DePuy.

Click here for the recall notice

This notice was shared with hospitals and surgeons regarding the ASR recall.

Smith & Nephew Press Conference about the Safety and Effectiveness of BHR

nospam@example.com (Patricia Walter) — Thu, 06 May 2010 21:26:41 -0700

Smith & Nephew Press Conference about the Safety and Effectiveness of Hip Resurfacing with the BHR -
Birmingham Hip Resurfacing Device

Review by Patricia Walter

May 6, 2010

Introduction: Joseph M. DeVivo, President of Smith & Nephew Orthopaedics

Joseph M. DeVivo, President of Smith & Nephew Orthopaedics (NYSE: SNN, LSE: SN), the maker of the BHR Hip introduced the press conference and discussed the safety and effectiveness of the BHR. He explained that over 125,000 patients worldwide have received a BHR since 1998. The BHR and the issue of metal sensitivity in patients with MOM (metal on metal) implants will be discussed. The purpose of this event is to deliver specific facts about the BHR and its unrivaled track record of success for active patients around the world.

Mr. DeVivo explained that information about hip resurfacing presented at the 2010 American Academy of Orthopedic Surgeons will be discussed. Recently, there has been negative information in the press about metal on metal devices which includes hip resurfacing devices like the BHR. The press has taken the failures of a few to cast doubts about all hip resurfacing.   It has omitted the successes of hip resurfacing and that 7 out of 10 surgeons performing hip resurfacing choose the BHR. Smith & Nephew feel the BHR is a safe and effective device providing successful hip resurfacing for patients worldwide.

Derek McMinn, MD, British surgeon and inventor of the BHR

Derek McMinn, MD, pioneering British surgeon and inventor of the BHR hip explained that the BHR has been proven successful by peer review data and his own clinical data. There are four main pieces of evidence that show the success of the BHR:

1.   The Australian Orthopaedic Association's National Joint Replacement Registry - tracked every hip resurfacing since 1998. Less than 1/3 of 1 percent of hip resurfacing failures are caused by an adverse tissue reaction.

2. In a 9 center Canadian study presented at the recent 2010 AAOS, 3 resurfacing patients out of 3400, less than 1/10 of 1 percent, experienced a tissue reaction.

3. Long Term data, from the Owestry outcome center, tracked 5000 BHR patients and now 518 BHR patients at 10 years of follow up. The study was carried out by 18 surgeons in 16 different countries. There was a 95% success rate at 10 years.

4. Mr. McMinn’s own clinical data started in 1997. He performed 3095 BHRs until end of 2009. At 12 years follow up, he has a 96% survivorship.

Therefore, according to McMinn, those 4 pieces of data from a large number of surgeons and his own clinical experience shows the BHR works. There have been adverse reactions reported in all of the studies, but these numbers are incredibly small. However, since MOM resurfacing has been going on in UK since 1991, when he did his first resurfacings, there have been a number of adverse reactions reported. One study from Oxford has over 30 presentations or publications of pseudotumors. In 2008, one percent of their patients were affected by this condition. Mr. McMinn explained that we need to examine what has happened in Oxford. They presented and published 610 BHRs in 2008. Those patients were operated on by 7 consultants and 30 trainees resulting in a large input from inexperienced surgeons. We know, explained McMinn, from a presentation from the last academy meeting that they have reported on poor surgery. The inclination angle of the cup should be 40 degrees; however, the Oxford pseudotumor group reported angles from 10.1 to 80.6 degrees. I need to stress, the high inclination angles up to 80.6 angles are completely unacceptable. Every BHR, Metal on Metal, Ceramic on Ceramic and metal on poly device will fail with that type of poor surgery.

McMinn explains that the adverse reactions for hip resurfacing are reported from 2 categories:

1. Poor results from well established BHRs put in badly causing edge loading, high metal wear and an adverse tissue reaction to lots of debris.

2. Poor results from implants that don’t work. The 4^th generation devices such as the Durom and ASR devices have both been associated with much higher failure rates than the BHR both on individual surgeon reports and Australian national registries. The adverse tissue reactions to the ASR are particularly prevalent. The UK reports around 7% revision rate for ASR resurfacing. ASR THR mom failures are also double than other devices. So the UK regulatory bodies are faced with reports of devices that are poor and adverse tissue reactions by well established devices put in badly.

Edwin Su, MD, of the Hospital for Special Surgery

Edwin Su, MD, of the Hospital for Special Surgery, agreed about the importance of hip resurfacing in the lives of patients.    After training with Mr. McMinn and Dr. Amstutz, he has completed over 1300 hip resurfacings with majority being BHRs. I can say with authority that this procedure can be a life restoring event for the patients. Metal on Metal hip resurfacing done with precise technique and a well designed implant can work. In appropriate patients, hip resurfacing can achieve nothing short of miraculous life changing results. Hip resurfacing allows patients to return to active pain free lives. Certain patient types do better with resurfacing than others. Good solid bone stock means you will do well. Poor bone stock means there is an elevated risk of a femoral neck fracture. This is common knowledge    Patients under age 65 have best bone stock. 92.7% of all resurfacings are in patients under 65. Patient selection is very important. The data shows men do better than women. Women require smaller components and are more difficult to align during surgery. Also women’s bones are less dense, so some women are not ideal candidates for hip resurfacing. Australian shows 80% resurfacings are in men. Resurfacing works better in men than women. Women of child bearing years are not recommend to have hip resurfacing.

Dr. Su explained about the issue of Implant alignment. If the components are misaligned, there will be an increased risk of metal wear because the surfaces will not be properly lubricated during regular physical activity. There is a resulting risk of adverse tissue reactions and possible revision surgery. Although this is true for most hip replacement surgery, it is especially true for resurfacing since the implants are less forgiving due to their precise manufacturing. This rate of adverse tissue reactions is extremely rare in resurfacing and less than ½ of 1 percent.

The literature, explained Dr. Su, shows experienced surgeons who have undergone appropriate training, can place a hip resurfacing device correctly. A surgeon not doing them on a regular basis has a greater chance of not achieving optimal results. It’s that simple explained Dr. Su.   This is true in any surgery in any specialty. While some implants perform better than others, good outcomes with hip resurfacing most often are achieved by experienced surgeons who have received excellent training and are careful in patient selection. Dr. Su has offered hip resurfacing since 2006 and has seen spectacular results since then.

Scott Marwin, MD, an orthopedic surgeon with New York University's Hospital for Joint Diseases

Dr. Marwin explained that the use of the BHR, after 12 years use worldwide and 4 years use in the states, remains an exciting option for some patients. It has never been suggested for all hip replacement surgery. Fewer than 10% of all patients are candidates. Fundamentally, it is a bone conserving procedure and saves a significant amount of healthy bone. Preservation of the basic structure of femur retains the natural size and angles of the joint and reduces any possibility of leg length discrepancy after surgery. Also patients’ soft tissue doesn’t have to adjust to a different set of shapes and kinematics that comes with a THR. Many patients forget which side has the BHR implant. Hip resurfacing also retains the patient’s anatomy which decreases the possibility of a dislocation. In a THR, the long metal neck can act like a lever on the edge of the metal cup and dislocate the ball out of the socket.   The natural femoral neck retained during hip resurfacing means incidence of dislocation is extremely rare. If a resurfacing patient needs a revision, they can receive a matching THR component to match the existing cup. Hip resurfacing reduces wear and leads to a longer life for the implant as compared to a THR. Dr. Marwin has implanted more than 750 hip resurfacing devices and can see what they can do for the active patient.

Summary by Joseph M. DeVivo

The BHR is different than other MOM devices on the market that are not performing up to standard. The BHR outperforms the gold standard for THRs in the core patient age group. Hip resurfacing gives patients their active life style back. BHR preserves so much healthy bone that it feels like a normal hip. More information can be found a www.hipsresurfacing.com

Question and Answers from Audience

Question: Terry Stanton, AAOS. Concerning the medical device alert in Britain - is it warranted and correctly crafted?

Answer: Dr. Su - It casts a general concern over MOM usage, but does not speak specifically to the BHR. BHR has its own clinical data and has not produced the type of concern other MOM device have. It stands on its own according to worldwide sources.

Q: Surgeon inexperience and poor technique – more globally in the US, what factor will it play?

A: Dr. Su - Where the BHR is concerned, as part of the FDA approval, it has mandated a very high level of training. Every surgeon is trained to same protocol.

Q: Canadian Study presented in New Orleans – follow up was 3 years. Comment on how solid the evidence is since the follow up is shorter.

A. Mr. McMinn - Important to look at what happens in first 3 years in hands of a new group of surgeons to hip resurfacing. The Oxford Group is reporting adverse reactions to metal debris in the early years. It is highly significant how a new group of trained surgeons get on. The fact that there are an incredibly low number of incidents of adverse reactions in a 9 center study with over 3000 patients speaks volumes for the devices and training of the surgeons. The longer term results are more important. The Australian registry has over 8000 people with an incredible low incidence of adverse reactions with survivorship at 95% for BHR at 8 years. The Oswestry registry with 518 patients at 10 years, shows a 95.4% implant survivorship. Phenomenally good results. In my own group, adverse reactions have occurred in 0.3% of my whole group. Out of 3095 BHR patients thru 2009, there were 10 adverse reactions. Unlike the Oxford Group, all the revisions have been fine. None were associated with soft tissue destruction. These were in the main, fluid collections requiring a bearing change to solve the problem. The patient made a totally uncomplicated recovery. I saw adverse reactions much later. Oxford was showing them 2 or 3 years after surgery.

Q. Metal sensivity and pseudotumros are always curious problems. In terms of devices, is there is less metal release in different devices?

A. Mr. McMinn - It is very clear who gets the pseudotumors. The retrievals from the Oxford Group show pseudotumors were associated with aged wear of the acetabular cup. With normal lubrication and normal wear, there are no pseudotumors. Clearly, if you want a MOM device to fail, implant it badly or design it badly so you get age loading and age wear which results in a high metal volume of debris early on.

Dr. Schmalzried discusses the ASR

nospam@example.com (Patricia Walter) — Tue, 16 Mar 2010 09:50:51 -0700

Advice to patients concerning the ASR

I suggest a few points that, I think, everyone can agree to (for any hip, including an ASR):

1. If you have pain or are in any way concerned - go see your surgeon.

2. There are some screening tests. Based on current experience, if blood (or serum) ion levels of Cr and Co are <5ppb, the likelihood a problem with the implant is low. If the level of either is >10ppb, the likelihood of a problem with the implant is increased. In either event, the next step would be an imaging study (ultrasound or MRI) to look for a fluid collection, or a cystic or solid mass - as evidence of an adverse local tissue response.

3. An aspiration of the joint may be appropriate a) to exclude infection as a cause of the joint dysfunction and b) the characteristics of the fluid may help in the differential diagnosis of a problem related to the metal-metal bearing.

I think that the first point is the most important. If you are concerned, go see your surgeon.

Thomas P. Schmalzried, M.D.

High Metal Ions, Pseudotumors, Metalosis & ALVAL by Patricia Walter 2008

nospam@example.com (Patricia Walter) — Fri, 10 Apr 2009 08:25:50 -0700

Patients and prospective patients are always concerned about the complications that could occur after a hip resurfacing surgery. The typical problems include femur neck fractures, dislocations, loose acetabular cups, improperly positioned acetabular cups, high metal ions, infections, pseudotumors, ALVAL and metalosis.

There has been a lot of discussion among patients on discussion groups about the high metal ion issue and pseudotumors. I am not a doctor or medically trained. I am a Patient Advocate, Hip Resurfacing Patient and Mechanical Engineer. I had the opportunity to attend the Second Annual U.S. Comprehensive Course on Total Hip Resurfacing Arthroplasty October 24–25, 2008 Los Angeles, CA. I listened to discussions about the metal ion issues and pseudotumors. I am going to explain what I learned in simple, non-medical terms since that is all I can do.

As an observer, I learned that the high metal ion issue has occurred in a small number of cases as a post op problem after a hip resurfacing. One of the most likely reasons, according to the experienced surgeons and presenters at the course, was the incorrect placement of the acetabular cup which resulted in additional wear on the bearing surface between the acetabular cup and the femur cap component. The hip resurfacing device is really a metal bearing made of High Carbon Cobalt-Chromium alloys. A bearing is designed to equally spread out the load over the load bearing components. If the components are not aligned properly, then only part of the bearing is loaded resulting in much more wear in that area possibly causing a high metal ion level. It was also explained that women seem to have more problems with high metal ions than men. Perhaps, this is due to the fact that most women use smaller sized hip resurfacing devices which causes more loading on the bearing surfaces than the men's larger sized devices.

When there is an abnormally high metal ion release from misplaced components, it seems to cause the surrounding tissue and bone to react adversely. The surrounding tissue and bone tends to become abnormal. Some doctors call the tissue reaction pseudotumors, AVAL (aseptic lymphocyte dominated vasculitis associated lesion), & others call it metalosis. Whatever name given to the abnormal reaction, it is not good to have this happening around the hip device since it could become loose, pain could result and possibly more severe medical reactions could happen.

There is concern among the hip resurfacing community about the reactions to the very high metal ion issue. At this time, to my understanding, there is not a standardized blood test available. Different labs use different methods and tests. There are not yet any specific guidelines as to what levels are too high for metal ions. There is a lot of research being done, but there are no standards yet.

This makes a surgeon's job to define and solve problems due to high metal ions difficult. Some doctors feel that patients with very high metal ions should have a revision of their hip resurfacing to a ceramic on ceramic THR. They don't want to take chances that even more serious problems could develop due to the high metal ions. Normally, from what I understand, the high metal ions are probably due either to the incorrect position of the acetabular cup causing very high wear on the hip resurfacing bearing device or due to the use of a small hip resurfacing device causing excessive loading on the bearing surfaces. So once again, the learning curve and experience of hip resurfacing surgeons is very important to prospective patients along with proper patient selection. It takes a great deal of experience to consistently place the acetabular cups at the proper angle and to know which smaller patients can successfully receive a hip resurfacing.

That is my layman's explanation of the high metal ion issue. I am posting a number of abstracts below by surgeons attending the Second Annual U.S. Comprehensive Course on Total Hip Resurfacing Arthroplasty October 24–25, 2008 Los Angeles, CA. Their articles will help explain more about the high metal ion issue, the small device issue used in many women and the acetabular cup placement issue.

Ceramic on Ceramic Hip Resurfacing by Mr. McMinn

nospam@example.com (Patricia Walter) — Tue, 03 Feb 2009 16:05:59 -0700

December 02, 2008

Linda is a massage therapist from Essex. She had a history of allergic reactions to cheap metal and as a result of this underwent a metal allergy test following her initial consultation. The allergy results showed that she was positive to Nickel and as a result she was recommended a ceramic on ceramic hip resurfacing, making her the first person to have an implant of this kind inserted. She is a very active person and possesses a black belt in karate.

Here she is interviewed at 2 months post op.

More Information available from the McMinn Center by Clicking here

McMinn Center Information

Allergy to Joint Replacements by Pat Campbell

nospam@example.com (Patricia Walter) — Mon, 17 Dec 2007 10:39:57 -0700

Hello

Pat Walter from Surface Hippies contacted me. I want to make it clear that I am not a qualified pathologist, nor a medical doctor, I am just a researcher with an interest in hip resurfacing and biomaterial compatibility. I run an independent implant retrieval research laboratory within the J. Vernon Luck Snr MD Orthopaedic Research Center at UCLA/Orthopaedic Hospital in Los Angeles. As such, I am the fortunate recipient of specimens and information from several orthopaedic surgeons, including Dr De Smet, who care enough about their patients to seek out knowledge to help solve patient problems, among which is metal sensitivity. I also want to emphasize that metal sensitivity to hip resurfacing replacements (or other hip replacements) is a problem that we (the orthopaedic community) are still learning about. (as well as the very much more common causes of problems with hip resurfacing such as fracture and loosening). Therefore, the material I include here should be considered preliminary and subject to change as more information is gained. That said, I hope your readers will find the attached description informative. Lastly, I would encourage the surface hippies to attend their regular follow up visits with their surgeons as the data obtained on the good as well as the problematical implants helps us all.

Sincerely

Pat Campbell PhD Assoc Prof. UCLA/Orthopaedic Hospital

Allergy to Joint Replacements

(from www.metalsensitivity.com – due online in 2008)

Occasional reports of joint replacement implant failure because of an apparent allergy to one of the metals in the device have appeared in the orthopaedic literature ever since metal implants were used. (1-3) It is now recognized that a small number of patients will suffer from a form of allergy or hypersensitivity to constituents of the metal-on-metal bearings even in the absence of high wear or a known metal sensitivity (4-6). The term ALVAL (aseptic lymphocytic vasculitis associated lesions) has been coined to describe the histological features associated with an allergy-like reaction in the joint tissues. (7, 8) It should be noted that some pathologists object to the inclusion of the “vasculitis” part of this new name and vasculitis in the strict sense of the word is not a prominent feature of the lesions.

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