Metal Toxicologist Part 1: Background & Expertise of toxicology expert Dr. Michael McCabe
Metal Toxicology Expert Part 2: DePuy ASR Hip Replacement Recall
Metal Toxicology Expert Part 3: Effects of elevated cobalt & chromium levels
Metal Toxicology Expert Part 4: Testing blood for cobalt and chromium - "Trace ...
Metal Toxicology Expert Part 5: What studies have been conducted regarding cobalt exposure?
Metal Toxicology Expert Part 6: What are the effects of elevated blood cobalt levels ...
Metal Toxicology Expert Part 7: Symptoms of Cobaltism
Metal Toxicology Expert Part 8: Effects of high levels of chromium
Metal Toxicology Expert Part 9: Effects of metal wear debris from metal hip implants
Metal Toxicologist Part 10: Cobalt blood levels after hip replacement revision surgery
Metal Toxicologist Part 11: Should all metal-on-metal hip implants be ...
Metal Toxicology Expert Part 12: Do high cobalt and chromium blood levels cause cancer ...
Saturday, March 3, 2012
Research: EFFECTS OF COBALT
Symptoms of cobaltism include irritability, fatigue, tinnitus, hearing loss, headaches, loss of coordination, cognitive decline, and depression.
Arthroprosthetic Cobaltism : Neurological & Cardiac Manifestations - The Journal of Bone & Joint Surgery
Oct 29,2010
International Agency for Research on Cancer
The IARC has determined that cobalt is possibly carcinogenic to humans.
The Journal of Bone & Joint Surgery, Volume 92, Issue 17
Many patients with metal-on-metal hip implants may develop renal impairment with time. Neurological and cardiac assessments should be considered for patients with a serum cobalt level of =7 µg/L. Revision arthroplasty should be considered for patients with periprosthetic metallosis and those with neurological or cardiac impairments temporally linked to elevated serum cobalt levels. Surgeons need to be aware that the high serum cobalt levels found in some patients with metal-on-metal hips may cause neurological or cardiac damage that is in part reversible with timely revision surgery.
US National Library of Medicine, National Institutes of Health
MoM hip bearings are being scrutinized due to high early failure rates and concerns that the results of the revision surgeries will be poor. However, orthopedic surgeons and the general medical community are unaware that patients with MoM bearings are also at risk for cobaltism. Medical providers need to know that hip arthroplasty implantees that present with symptom complexes that include tinnitus, deafness, vertigo, visual changes, rashes, hypothyroidism, tremor, dyspnea on exertion, mood disorders, dementia, heart failure, and peripheral neuropathy may be presenting arthroprosthetic cobaltism. These patients need to be asked if they have had a hip replacement and if so what type. For those patients implanted with a MoM bearing or those with a history of hip revision for a failed ceramic bearing obtaining a [Co] is indicated. MoM implantees with renal failure are a particularly high risk for cobaltism. Patients with a cobalt levels of greater than 7 mcg/l bear observation of neurologic and cardiac function. Those patients with levels greater than 20 should be advised to have revision of their hip arthroplasty to a bearing that eliminates cobalt. Most patients implanted with MoM bearing have cobalt levels greater than those allowed in industry and cobalt exposed workers may have an increased incidence of subclinical cognitive and cardiac impairments.
Department of Orthopaedics, Rheumatology and Musculoskeletal Surgery, University of Oxford
The Journal of Bone and Joint Surgery (American) 0:JBJS.J.00125-jbjs.J00125 (2010)
A serum cobalt level of >7 µg/L indicates possible periprosthetic metallosis. A normal serum cobalt level is 0.19 µg/L, and 95% of those who are unexposed to cobalt have a value of <0.41 µg/L.
A serum cobalt level of >1 µg/L indicates excessive cobalt exposure, and levels of >5 µg/L are considered toxic. Patients may become high risk for cobaltism if renal function declines and those in which ASR implants are used. [Mine is 16.9 ug/L]
A recent letter to the BMJ (Arthroprosthetic cobaltism associated with metal on metal implants. BMJ 2012;344:e430) describes several patients who received the metal-on-metal hip implants who developed progressive hip pain, elevated cobalt levels, cognitive impairment, neuropathy, and cardiomyopathy. Associated symptoms included new onset depression, anxiety, tinnitus, and thyroid abnormalities.
Effects of Cobalt Nanoparticles on Human T Cells
Arthroprosthetic Cobaltism : Neurological & Cardiac Manifestations - The Journal of Bone & Joint Surgery
Oct 29,2010
International Agency for Research on Cancer
The IARC has determined that cobalt is possibly carcinogenic to humans.
The Journal of Bone & Joint Surgery, Volume 92, Issue 17
Many patients with metal-on-metal hip implants may develop renal impairment with time. Neurological and cardiac assessments should be considered for patients with a serum cobalt level of =7 µg/L. Revision arthroplasty should be considered for patients with periprosthetic metallosis and those with neurological or cardiac impairments temporally linked to elevated serum cobalt levels. Surgeons need to be aware that the high serum cobalt levels found in some patients with metal-on-metal hips may cause neurological or cardiac damage that is in part reversible with timely revision surgery.
US National Library of Medicine, National Institutes of Health
MoM hip bearings are being scrutinized due to high early failure rates and concerns that the results of the revision surgeries will be poor. However, orthopedic surgeons and the general medical community are unaware that patients with MoM bearings are also at risk for cobaltism. Medical providers need to know that hip arthroplasty implantees that present with symptom complexes that include tinnitus, deafness, vertigo, visual changes, rashes, hypothyroidism, tremor, dyspnea on exertion, mood disorders, dementia, heart failure, and peripheral neuropathy may be presenting arthroprosthetic cobaltism. These patients need to be asked if they have had a hip replacement and if so what type. For those patients implanted with a MoM bearing or those with a history of hip revision for a failed ceramic bearing obtaining a [Co] is indicated. MoM implantees with renal failure are a particularly high risk for cobaltism. Patients with a cobalt levels of greater than 7 mcg/l bear observation of neurologic and cardiac function. Those patients with levels greater than 20 should be advised to have revision of their hip arthroplasty to a bearing that eliminates cobalt. Most patients implanted with MoM bearing have cobalt levels greater than those allowed in industry and cobalt exposed workers may have an increased incidence of subclinical cognitive and cardiac impairments.
Theoretical, desirable features of second-generation metal-on-metal (MoM) hip prostheses have led to their widespread use. However, the bearing surfaces, consisting of complex cobalt-chromium alloys, are subject to wear and the release of cobalt and chromium (CoCr) nanoparticles. These nanoparticles can reduce cellular viability, induce DNA damage, lead to chromosomal aberrations, and possibly stimulate increased metal hypersensitivity. Clinically, the effects can be both local (soft-tissue reactions) and systemic (arthroprosthetic cobaltism). This review assesses the literature concerning the in vitro and in vivo cytotoxic, genotoxic, and immunotoxic effects of CoCr wear particles, which is increasingly important in view of the large number of MoM arthroplasties performed.
The Journal of Bone and Joint Surgery (American) 0:JBJS.J.00125-jbjs.J00125 (2010)
A serum cobalt level of >7 µg/L indicates possible periprosthetic metallosis. A normal serum cobalt level is 0.19 µg/L, and 95% of those who are unexposed to cobalt have a value of <0.41 µg/L.
A serum cobalt level of >1 µg/L indicates excessive cobalt exposure, and levels of >5 µg/L are considered toxic. Patients may become high risk for cobaltism if renal function declines and those in which ASR implants are used. [Mine is 16.9 ug/L]
Department of Orthopedics, The First Affiliated Hospital of Soochow University, People's Republic of China released this study marking the potential gentoxic/cytotoxic effects that cobalt might have on the patients T cells. In genetics, genotoxicity describes a deleterious action on a cell's genetic material affecting its integrity.
Cytotoxicity is the quality of being toxic to cells. T cells or T lymphocytes belong to a group of white blood cells known as lymphocytes, and play a central role in cell-mediated immunity. Lymphocytes identify invaders in the body and destroy them. In this case, we would be targeting cobalt as an invader in the body which the system would want to wipe out. If the T lymphocytes are not working properly and are inhibited, problems could arise of various sorts. The function of T cells and B cells is to recognize specific “non-self” antigens, during a process known as antigen presentation. Once they have identified an invader, the cells generate specific responses that are tailored to maximally eliminate specific pathogens or pathogen infected cells. B cells respond to pathogens by producing large quantities of antibodieswhich then neutralize foreign objects like bacteria and viruses. These tests were conduced in vitro. that is, they are lab experiments NOT conducted on humans or organisms.
Limited information is available on the potential risk of degradation products of metal-on-metal bearings in joint arthroplasty. The aim of this study was to investigate the cytotoxicity and genotoxicity of orthopedic-related cobalt nanoparticles on human T cells in vitro. T cells were collected using magnetic CD3 microbeads and exposed to different concentrations of cobalt nanoparticles and cobalt chloride. Cytotoxicity was evaluated by methyl thiazolyl tetrazolium and lactate dehydrogenase release assay. Cobalt nanoparticles dissolution in culture medium was determined by inductively coupled plasma-mass spectrometry. To study the probable mechanism of cobalt nanoparticles effects on T cells, superoxide dismutase, catalase, and glutathione peroxidase level was measured. Cobalt nanoparticles and cobalt ions could inhibit cell viability and enhance lactate dehydrogenase release in a concentration- and time-dependent manner (P < 0.05). The levels of cobalt ion released from cobalt nanoparticles in the culture medium were less than 40% and increased with cobalt nanoparticles concentration. Cobalt nanoparticles could induce primary DNA damage in a concentration-dependent manner, and the DNA damage caused by cobalt nanoparticles was heavier than that caused by cobalt ions. Cobalt nanoparticles exposure could significantly decrease superoxide dismutase, catalase, and glutathione peroxidase activities at subtoxic concentrations (6 μM, <CC(50)). These findings suggested that cobalt nanoparticles could generate potential risks to the T cells of patients suffer from metal-on-metal total hip arthroplasty, and the inhibition of antioxidant capacity may play important role in cobalt nanoparticles effects on T cells.
Imperial College London, Department of Musculoskeletal Surgery, London
Blood metal ions have been widely used to investigate metal-on-metal hip replacements, but their ability to discriminate between well-functioning and failed hips is not known. The Medicines and Healthcare products Regulatory Agency (MHRA) has suggested a cut-off level of 7 parts per billion (ppb). We performed a pair-matched, case-control study to investigate the sensitivity and specificity of blood metal ion levels for diagnosing failure in 176 patients with a unilateral metal-on-metal hip replacement. We recruited 88 cases with a pre-revision, unexplained failed hip and an equal number of matching controls with a well-functioning hip. We investigated the 7 ppb cut-off level for the maximum of cobalt or chromium and determined optimal mathematical cut-off levels from receiver-operating characteristic curves. The 7 ppb cut-off level for the maximum of cobalt or chromium had a specificity of 89% and sensitivity 52% for detecting a pre-operative unexplained failed metal on metal hip replacement. The optimal cut-off level for the maximum of cobalt or chromium was 4.97 ppb and had sensitivity 63% and specificity 86%. Blood metal ions had good discriminant ability to separate failed from well-functioning hip replacements. The MHRA cut-off level of 7 ppb provides a specific test but has poor sensitivity.
Cytotoxicity is the quality of being toxic to cells. T cells or T lymphocytes belong to a group of white blood cells known as lymphocytes, and play a central role in cell-mediated immunity. Lymphocytes identify invaders in the body and destroy them. In this case, we would be targeting cobalt as an invader in the body which the system would want to wipe out. If the T lymphocytes are not working properly and are inhibited, problems could arise of various sorts. The function of T cells and B cells is to recognize specific “non-self” antigens, during a process known as antigen presentation. Once they have identified an invader, the cells generate specific responses that are tailored to maximally eliminate specific pathogens or pathogen infected cells. B cells respond to pathogens by producing large quantities of antibodieswhich then neutralize foreign objects like bacteria and viruses. These tests were conduced in vitro. that is, they are lab experiments NOT conducted on humans or organisms.
Limited information is available on the potential risk of degradation products of metal-on-metal bearings in joint arthroplasty. The aim of this study was to investigate the cytotoxicity and genotoxicity of orthopedic-related cobalt nanoparticles on human T cells in vitro. T cells were collected using magnetic CD3 microbeads and exposed to different concentrations of cobalt nanoparticles and cobalt chloride. Cytotoxicity was evaluated by methyl thiazolyl tetrazolium and lactate dehydrogenase release assay. Cobalt nanoparticles dissolution in culture medium was determined by inductively coupled plasma-mass spectrometry. To study the probable mechanism of cobalt nanoparticles effects on T cells, superoxide dismutase, catalase, and glutathione peroxidase level was measured. Cobalt nanoparticles and cobalt ions could inhibit cell viability and enhance lactate dehydrogenase release in a concentration- and time-dependent manner (P < 0.05). The levels of cobalt ion released from cobalt nanoparticles in the culture medium were less than 40% and increased with cobalt nanoparticles concentration. Cobalt nanoparticles could induce primary DNA damage in a concentration-dependent manner, and the DNA damage caused by cobalt nanoparticles was heavier than that caused by cobalt ions. Cobalt nanoparticles exposure could significantly decrease superoxide dismutase, catalase, and glutathione peroxidase activities at subtoxic concentrations (6 μM, <CC(50)). These findings suggested that cobalt nanoparticles could generate potential risks to the T cells of patients suffer from metal-on-metal total hip arthroplasty, and the inhibition of antioxidant capacity may play important role in cobalt nanoparticles effects on T cells.
Imperial College London, Department of Musculoskeletal Surgery, London
Blood metal ions have been widely used to investigate metal-on-metal hip replacements, but their ability to discriminate between well-functioning and failed hips is not known. The Medicines and Healthcare products Regulatory Agency (MHRA) has suggested a cut-off level of 7 parts per billion (ppb). We performed a pair-matched, case-control study to investigate the sensitivity and specificity of blood metal ion levels for diagnosing failure in 176 patients with a unilateral metal-on-metal hip replacement. We recruited 88 cases with a pre-revision, unexplained failed hip and an equal number of matching controls with a well-functioning hip. We investigated the 7 ppb cut-off level for the maximum of cobalt or chromium and determined optimal mathematical cut-off levels from receiver-operating characteristic curves. The 7 ppb cut-off level for the maximum of cobalt or chromium had a specificity of 89% and sensitivity 52% for detecting a pre-operative unexplained failed metal on metal hip replacement. The optimal cut-off level for the maximum of cobalt or chromium was 4.97 ppb and had sensitivity 63% and specificity 86%. Blood metal ions had good discriminant ability to separate failed from well-functioning hip replacements. The MHRA cut-off level of 7 ppb provides a specific test but has poor sensitivity.
SWIMMING
I receive provincial colours and compete at SA Championships, schools level. Without any training my swimming is brilliant, and I realise I was born to swim. I never competed after school, until friends of mine encouraged me to start swimming again for the Masters league in 2009.
September 2009
I officially join Amakhosi Masters Swimming Club in East London, and start training for South African Masters Championships.
March 2010
I have to back out of the National Championships due to hip pain and my impending hip replacement.
July 2010
This is hip resurfacing surgery month and I cannot wait to get back into the water.
November 2010
I register for SA Masters Championships, taking place in 4 months, and start a moderate training routine. The swimming makes me feel great, and I start feeling competitive again.
March 2011
I swim breaststroke, backstroke and freestyle. I bring home 6 medals (2 gold; 3 silver). I felt elated and empowered again. Breaststroke was difficult, as it's my strongest stroke and I was not ready to train for it, so the 50m I had swam left me with terrible pain later in the day and the days following. My times were better than my goal times, and this experience has pushed me to go for World Championships and Masters Olympics. Etana promotes my achievements - and sponsored me. Read the article here.
November 2011
I register for 2012 SA Masters Championships and I'm determined to qualify for the 2012 FINA World Masters in Italy in July. I joined Virgin Active to have access to the pool and my training starts.
December 2011
Tinnitus and headaches are preventing me from focusing on anything, and I stop training and stay out of the water.
January 2012
I have my first swim in a month, and later that night I suffer from the most painful headache and my ears feel blocked. I tell the team that I have health problems and that my training is suffering.
February 2012
I find out about the DePuy recall and completely withdraw from Masters Championships this year, blowing my chance of qualifying for the World Masters Championships. I'm devastated because I know I will need to undergo revision surgery, and that I will be out of the 2013 championships as well. I also know that I will miss the 2013 Pan-American Masters in Florida. Not only will my swimming career be set back by 2 years, but I am missing out on all the sponsored travel to Europe and USA during 2012 and 2013. I also wonder if my FINA-approved racing suits will fit me again - after spending R5,000 on them.
I am honestly heart -broken. This is a bitter pill to swallow.
PROCEDURES: MRI
29/02/2012
MRI was done today.
I asked what protocol was used, because MRI's done on patients with metal components are difficult since the metal content of the implant creates large distortions (warping) in the generated images. An optimized MR imaging technique has been developed in New York and Los Angeles, called the MAVRIK and the MARS protocol. It's a newer imaging technique to further reduce metal artifact in generated images, allowing for even better visualization of the bone and soft tissues surrounding metal-on-metal hips.
The radiologist had no idea what I was talking about:(
Read the published study on MAVRIK protocol MRI by the Department of Radiology and Imaging, Hospital for Special Surgery, New York (September 2011)
The study confirms:
- Visualization of the synovium was significantly better on MAVRIC image
- Synovitis was detected only on the MAVRIC images
- Osteolysis was detected only on the MAVRIC images
02/03/2012
Consultation with my surgeon today. He has not heard of this specific protocol, but the most important thing he said was that there is no problem with the prosthesis and that everything looked normal. The radiologist comments that if there was a small lesion, it would not be seen due to the artifact. So ultimately, the MRI is useless.
03/03/2012
I've had sleepless nights worrying about this problem ,so I have a plan:
1. I need to get a second opinion.
2. I need to question the radiologist about developing the MAVRIK protocol and what it will entail. If this option is not available to me in South Africa, I intend on approaching the Sports Science Institute to look into it. (Why do I get the feeling that South Africa is always the last to know about advancements in this field??)
MRI was done today.
I asked what protocol was used, because MRI's done on patients with metal components are difficult since the metal content of the implant creates large distortions (warping) in the generated images. An optimized MR imaging technique has been developed in New York and Los Angeles, called the MAVRIK and the MARS protocol. It's a newer imaging technique to further reduce metal artifact in generated images, allowing for even better visualization of the bone and soft tissues surrounding metal-on-metal hips.
The radiologist had no idea what I was talking about:(
.jpg) |
Left: MRI of right hip resurfacing using optimized metal artifact reduction imaging techniques. There is significant artifact around the metallic components, which limits the ability to visualize the surrounding bone and soft tissue. Right: MRI of right hip resurfacing using MAVRIC. Greater clarity of the surrounding soft tissues (red arrows) and surrounding bone (yellow arrow) is shown. |
The study confirms:
- Visualization of the synovium was significantly better on MAVRIC image
- Synovitis was detected only on the MAVRIC images
- Osteolysis was detected only on the MAVRIC images
02/03/2012
Consultation with my surgeon today. He has not heard of this specific protocol, but the most important thing he said was that there is no problem with the prosthesis and that everything looked normal. The radiologist comments that if there was a small lesion, it would not be seen due to the artifact. So ultimately, the MRI is useless.
03/03/2012
I've had sleepless nights worrying about this problem ,so I have a plan:
1. I need to get a second opinion.
2. I need to question the radiologist about developing the MAVRIK protocol and what it will entail. If this option is not available to me in South Africa, I intend on approaching the Sports Science Institute to look into it. (Why do I get the feeling that South Africa is always the last to know about advancements in this field??)
Monday, February 27, 2012
Effects of Cobalt & Chromium in your Body
There is a very unique aspect to metal-on-metal hip implants that has been found dangerous to hip implant patients. In light of recent hip implant recalls, surgeons have come forward to reveal high failure rates in many large diaphragm metal-on-metal implants, and the significant damage they cause by way of metal wear debris. Click here for a list of metal-on-metal implants that may cause elevated cobalt and chromium blood levels. Metal wear debris has been found to cause soft tissue damage in and around the hip joint. Many studies suggest this is caused by both direct killing of the tissue, and also by a stimulation of an inflammatory process. Often patients who have been implanted with large diaphragm metal-on-metal hip implants have discovered pseudo-tumors growing in the tissue surrounding the metal hip. These benign tumors are growths of pus and scar tissue resulting from this inflammatory process that has occurred in response to the foreign object implanted in the body. (continued below)
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This inflammatory process can also affect the body's immune response by infiltrating the T-lymphocytes, or T-cells, that drive up the body's hypersensitivity response. This is where the health consequences to cobalt and chromium become a larger concern. Cobalt has been known to trigger cardiomyopathy (heart problems), hypothyroidism, and both cobalt and chromium may possibly contribute to neurotoxic outcomes, as well as carcinogenesis, or cancer. According to the Agency for Toxic Substances & Disease Registry, cancer has been shown in animals when cobalt was placed directly into the muscle or under the skin. Based on this research, the World Health Organization's International Agency for Research on Cancer includes cobalt found in hard metals as a potential carcinogen for humans. Additional Reading: Four-year study of cobalt and chromium blood levels in patients managed with two different metal-on-metal total hip replacements, March 2003, Journal of Orthopaedic Research Read about the risks of metal-on-metal hip implants for pregnant women | |||||
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