Archive for category Metal on Metal Hip Implants
Total hip replacement, what can go wrong
Posted by Mitchell B. Sheinkop, M.D. in Hip Pain, Metal on Metal Hip Implants, Osteoarthritis, Regenerative Pain Center, Stem Cells on May 9, 2012
Introduction and background
While the benefits of total hip replacements are numerous, there is a known incidence of associated pain leading to early revision. Have attempts at improving the prosthetic implant, shortened lengths of hospital stay, minimally invasive procedures and metal on metal bearings been a process of revolution or as in the case of Gulliver, devolution?
The goal of the surgeon has historically been pain relief and a 20-year plus satisfactory outcome when performing a total hip. More recently, survivorship prioritization seems to have been replaced by restoration of hip anatomical geometry, thereby optimizing muscle tension and strength, equalization of leg lengths, and enhancement of hip stability all via modularity. The newer generations of prostheses have been designed in an attempt to facilitate and accommodate the latest fads in surgical approaches so as to lessen the scar length, perhaps minimize muscle damage-still a matter of debate-and return the patient to full activity status in days or weeks rather than months.
I just received an AMA alert that by 2030, 42% of Americans will be obese. Short incision, less hospital stay, prompt return to activity, who are we kidding? Lets look more closely at the cost of supposed progress in the newest prosthetic designs.
Metal Fretting and Corrosion. This has been reported with cobalt chrome and cobalt chrome- titanium junctions. The more modularity and junctions between metals, the more potential metal debris generation. Metal on metal bearings produce small metallic wear debris. Furthermore, elevated blood serum ion levels and metal hypersensitivity resulting in an adverse local tissue reaction may occur with metal-metal articulate surface bearings causing premature failure due to osteolysis, aseptic loosening and pseudo tumor formation.
So what should you do and look for whether or not you are in pain after a total hip replacement?
Evaluation for infection-a screening serum ESR, C-Reactive Protein, and WBC. If any of these are abnormal, a hip aspiration need be performed.
Serum metal ion levels-serum chromium ion levels above 17ug/L and cobalt ion levels above 19ug/L suggest metallosis within the joint. Pseudotumors have been found at lower levels and are identified by ultrasound and CT scans. In the United Kingdom, the cut off level is 7 parts per billion (7ppb) chromium or cobalt.
Metal hypersensitivity-Nickel is the worst offender but chromium and cobalt may play a role. The problem is the area is still poorly understood with the only available testing including patch testing and the lymphocyte transformation test.
Radiographic analysis-Your physician will look for signs of loosening, osteolysis and pseudotumor formation
If you have a painful total hip replacement, you need an evaluation.
There is another consideration, postpone or avoid the replacement. Might Regenerative medicine and stem cell management, help control you pain and possibly postpone or even help avoid a total joint replacement?
Mitchell B. Sheinkop, M.D.
847-390-7666 or 312-475-1893
1565 N. LaSalle Street
Chicago, Illinois 60610
This Week’s Top Stories
Posted by Mitchell B. Sheinkop, M.D. in Hip Pain, Metal on Metal Hip Implants, Regenerative Pain Center, Stem Cells on March 27, 2012
British Hip Society recommends against use of stemmed, large diameter, metal-on-metal implants in primary total hip replacements.
Based on discussions held at its annual meeting, the British Hip Society (BHS) has issued a statement on the use of large diameter metal-on-metal bearing total hip replacements. BHS advises that stemmed, large diameter metal-on-metal primary total hip replacements using bearings of 36 mm or greater should no longer be performed until more evidence is available, except in properly conducted and ethically approved research studies. The advice does not apply to hip resurfacing. In addition, BHS endorsed guidance recently issued by the United Kingdom’s Medicines and Healthcare Products Regulatory Agency (MHRA), calling for annual monitoring for the life of the implant, as a precautionary measure.
Other News
FDA committee to discuss reports of joint destruction associated with anti-NGF drugs.
The U.S. Food and Drug Administration (FDA) plans to hold a meeting next week to discuss the anti-nerve growth factor (Anti-NGF) drug class that is currently under development, along with safety issues possibly related to the drugs. Anti-NGF drugs are being developed for the treatment of chronic painful conditions such as osteoarthritis, chronic lower back pain, cancer pain, and other conditions. An advisory committee will be asked to determine whether reports of joint destruction represent a safety signal related to the anti-NGF class of drugs, and whether the risk-benefit balance for these drugs favors their continued development as analgesics.
Sheinkop meets with Regenexx in Colorado to evaluate new office based needle arthroscopic system
While it is true that I was skiing last week in Vail, while I vacationed, I still worked on assuming a leadership position in the new world of regenerative medicine. What I as an individual am able to contribute is my background and experience in research and clinical practice of treating arthritis with joint replacement surgery. Now I am dedicating myself as an orthopedic surgeon to avoiding or postponing joint replacement. When arthritis is debilitating and the X-ray is that of bone on bone, there is still an indication for a new hip or a new knee. But patient beware, there are restrictions inherent in a new joint. My life-long biking, skiing and fly fishing buddy, has relatively severe arthritis of his left knee. Yet he still can bike faster and ski better than me-I out fish him-because he has taken my counsel and postponed, maybe avoid a knee replacement via Regenerative Medicine.
To learn if you are a candidate for regenerative medicine, feel free to call
Mitchell B. Sheinkop, M.D.
847-390-7666 or 312-475-1893
1565 N. LaSalle St, Chicago, IL 60610
Questions and Answers About Metal-on-Metal Hip Implants
Posted by Mitchell B. Sheinkop, M.D. in Metal on Metal Hip Implants on June 2, 2011
(From the American Academy of Orthopedic Surgeons Patient Information initiative)
On May 6, 2011, the Food and Drug Administration (FDA) issued a postmarket surveillance studies of total metal-on-metal hip replacement devices. A postmarket surveillance study monitors adverse events after a device has been approved or cleared by the FDA
Although the vast majority of patients have not had any problems with MoM implants, orthopaedic surgeons and the FDA are concerned because a few cases reported in the peer-reviewed literature and through a British database have involved patients who had local hip symptoms (pain and swelling) as well as other medical concerns seemingly unrelated to the hip.
The following is the patient-education portion of the FDA’s patient health communication:
How often should I follow-up with my orthopaedic surgeon?
If you develop new or significantly worsening symptoms or problems with your hip, including pain, swelling, numbness and/or a change in ability to walk, contact your orthopaedic surgeon right away.
What symptoms might a metal-on-metal hip implant cause?
Symptoms may include hip/groin pain, local swelling, numbness or changes in your ability to walk. There are many reasons a patient with a metal-on-metal hip implant may experience such symptoms and it is important that you contact your surgeon to help determine why you are having them.
Are there other medical effects that can occur with my metal-on-metal hip implant system?
Metal-on-metal hip implants, like other types of hip implants, are known to have adverse events, including infection and joint dislocation. There are some case reports of the metal particles causing a reaction around the joint, leading to deterioration of the tissue around the joint, loosening of the implant, and failure of the device, as well as some of the symptoms described above. In addition, some metal ions from the implant may enter into the blood stream. There have been a few recent case reports of patients with metal-on-metal hip implants developing a reaction to these ions and experiencing medical problems that might have been related to their implants, including effects on the nervous system, heart, and thyroid gland.
What should I do if I am experiencing adverse events associated with my metal-on-metal hip implant?
1. If you are experiencing hip/groin pain, difficulty walking or a worsening of your previous symptoms, you should make an appointment to see your orthopaedic surgeon for further evaluation of your implant. Your orthopaedic surgeon may wish to perform a physical exam and an evaluation based on your symptoms.
2. If you experience any new symptoms or medical conditions in your body other than at your hip, you should report these to your primary physician and remind them that you have a metal-on-metal hip implant system during their evaluation.
What does it mean when I see that a hip implant system has been “recalled?”
A hip system may be recalled by the manufacturer for a number of reasons. If your device is recalled, this does not necessarily mean that the device needs to be removed and replaced. In some cases, the recall just calls for different or more frequent monitoring. It is important to discuss the reason for the recall with your surgeon to determine the most appropriate course of action. If you are unsure if your hip implant was recalled, consult with your orthopaedic surgeon. Additional information on the recall can be obtained from the manufacturer or from: FDA Medical Device Recall InformationFDA Medical Device Recall Information
With the risk of adverse reactions to metal-on-metal hip implant systems, why are these devices still being offered to patients?
It is known that every different type of hip implant system has its own set of risks as well as its own set of benefits. FDA’s assessment of medical devices such as metal-on-metal (MoM) hip implants is based on a risk-benefit ratio with the data available. MoM hip implants overall have been shown to provide significant benefits (e.g., high survivorship) in certain patient populations. Although the exact prevalence of adverse reactions to metal-debris is not known, current experience leads us to consider the adverse outcomes to be relatively low or equal to other types of hip implants. Thus, for many patients, currently available information supports a favorable risk-benefit ratio.
Concerns about Metal-on-Metal Hip Implants
Posted by Mitchell B. Sheinkop, M.D. in Metal on Metal Hip Implants on February 14, 2011
FDA Communication, February 09, 2011
All artificial hip replacement systems have risks related to implant or material wear. Metal-on-metal hip (MoM) replacement systems have unique risks in addition to the general risks of all hip implant systems.
In April 2010, the United Kingdom’s (U.K.) Medicines and Healthcare products Regulatory Agency (MHRA) issued a medical device alert that included specific recommendations for patients implanted with MoM hip replacements. The recommendations included blood tests and imaging for patients with painful MoM hip implants.
There are several differences between the U.K. and U.S. regulatory systems and some of the U.K. data may not be directly applicable to the experience in the US. For example, some of the devices available in U.K. are not marketed in U.S. Therefore; the frequency of reactions, in the U.S. is unknown. For this reason, FDA is in the process of gathering additional information about adverse events in people with metal-on-metal hip implants.
At the current time, there is no evidence to support the need for checking metal ion levels in the blood or special imaging if patients with MoM hip implants have none of the signs or symptoms described above and the orthopaedic surgeon feels the hip is functioning properly. The FDA is recommending that asymptomatic patients with MoM hip implants continue to follow-up with their orthopaedic surgeon as prescribed.
If patients with MoM hip implants develop any concerns, it is very important for them to make appointments with their orthopaedic surgeons promptly for further evaluation.
If patients with MoM hip implants develop any new or worsening symptoms outside of their hips, or if they are referred to doctors to evaluate new conditions, they should let the doctors know that they have MoM hips.
From the February 11, 2011, American Academy of Orthopedic Surgeons
Communication blast
“FDA issues communication on metal-on-metal hip components.
The U.S. Food and Drug Administration (FDA) has posted a public health communication about metal-on-metal (MOM) hip components used in total hip arthroplasty (THA). The communication addresses recent concerns about MOM hip implant systems, and provides specific information for orthopaedic surgeons on these devices, including their effectiveness and general considerations before, during, and after arthroplasty. In addition, the communication provides information for other healthcare professionals regarding treatment to patients with a MOM implant, as well as for patients who have or are considering MOM implants.
AAOS appreciates this thorough and well-considered look at the concerns surrounding the use of these implants. With the patient’s safety, health, and quality of life always in mind, the members of the AAOS will continue to work with device makers and agencies such as the FDA to share knowledge and communicate any potential concerns.”
Because the amount of information exceeds the capacity of my Blog to learn more, go to WWW.FDA.GOV/medical devices and enter metal on metal hip February 09, 2011
For the week of February 21, 2011, you will learn about stem cells and the hip as there are lots of patients considering a hip replacement as well as many recipients of hip resurfacing on one side who are deciding what to do about the other hip
