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Prosthetic hip-associated cobalt toxicity (PHACT) is caused by elevated blood cobalt concentrations after hip arthroplasty. The aim of this study is to determine which symptoms are reported most frequently and in what type of bearing. We also try to determine the blood level of cobalt concentrations associated with toxicological symptoms. A systematic review was conducted on the 10th of July according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A methodological quality assessment (risk of bias (RoB)) was performed. Primary outcomes were the reported symptoms of cobalt toxicity and the level of cobalt concentrations in blood. These levels were associated with toxicological symptoms. A total of 7645 references were found of which 67 relevant reports describing 79 patients. The two most used bearings in which PHACT was described were metal-on-metal (MoM) bearings (38 cases) and revised (fractured) ceramic-on-ceramic (CoC) bearings where the former ceramic head was replaced by a metal head (32 cases). Of all reported symptoms, most were seen in the neurological system, of which 24% were in the sensory system and 19.3% were in central/peripheral system, followed by the cardiovascular (22.1%) system. The mean cobalt concentration for MoM-bearings was 123.7 ± 96.8 ppb and 1078.2 ± 1267.5 ppb for the revised fractured CoC-bearings. We recommend not to use a metal-based articulation in the revision of a fractured CoC bearing and suggest close follow-up with yearly blood cobalt concentration controls in patients with a MoM bearing or a revised fractured CoC bearing. Level of Evidence: Level V, systematic review

Prosthetic hip-associated cobalt toxicity (PHACT) is caused by elevated blood cobalt concentrations after hip arthroplasty.The aim of this study is to determine which symptoms are reported most frequently and in what type of bearing. We also try to determine the blood level of cobalt concentrations associated with toxicological symptoms.A systematic review was conducted on the 10th of July according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A methodological quality assessment (risk of bias (RoB)) was performed. Primary outcomes were the reported symptoms of cobalt toxicity and the level of cobalt concentrations in blood. These levels were associated with toxicological symptoms. A total of 7645 references were found of which 67 relevant reports describing 79 patients.The two most used bearings in which PHACT was described were metal-on-metal (MoM) bearings (38 cases) and revised (fractured) ceramic-on-ceramic (CoC) bearings where the former ceramic head was replaced by a metal head (32 cases).Of all reported symptoms, most were seen in the neurological system, of which 24% were in the sensory system and 19.3% were in central/peripheral system, followed by the cardiovascular (22.1%) system.The mean cobalt concentration for MoM-bearings was 123.7 +/- 96.8 ppb and 1078.2 +/- 1267.5 ppb for the revised fractured CoC-bearings.We recommend not to use a metal-based articulation in the revision of a fractured CoC bearing and suggest close follow-up with yearly blood cobalt concentration controls in patients with a MoM bearing or a revised fractured CoC bearing.

Cobalt toxicity in patients with hip arthroplasty is a rare complication, but it should be considered in those patients who, after a ceramic fracture, were implanted with a metal-on-polyethylene prosthesis. The complete removal of ceramic particles during revision surgery can be complicated. If the bearing surface is replaced with a metal-on-polyethylene prosthesis, these residual ceramic particles may wear down the chrome-cobalt head, producing localised metallosis. This can trigger blood metal ion levels to rise, causing systemic toxicity. Visual and auditory alterations, cognitive deterioration, hypothyroidism, neuropathy, cardiomyopathy, anorexia, fatigue, diabetes, polycythemia, and respiratory and cutaneous symptoms are some of the clinical manifestations of prosthetic cobaltism.A young patient presented with multiorgan failure secondary to cobalt toxicity after a ceramic fracture and revision with a metal-on-polyethylene prosthesis; his serum cobalt and chromium levels were 652 μg/L and 270 μg/L, respectively. The patient needed a heart transplant after presenting with cobalt-induced cardiogenic shock.In a patient with a ceramic fracture who is subjected to revision surgery with a metal-on-polyethylene bearing, it is necessary to rule out the possibility of cobalt intoxication. Serum cobalt levels20 μg/L are inadmissible; in these cases, surgical treatment should be considered in the short term. A wide synovectomy and replacement of components should be performed with hard friction options, preferably with a ceramic-on-ceramic prosthesis.

This study was designed to determine whether systemic cobalt toxicity as an adverse event could be documented using the Food and Drug Administration's (FDA) Manufacturer and User Facility Device Experience (MAUDE) database for cobalt-chromium containing hip implant recipients. Class 3 JohnsonJohnson (JJ)/DePuy devices were chosen for analysis because of the large number of adverse event reports related to their Pinnacle and ASR XL Acetabular hip replacement systems. A secondary goal was to characterize the reporters who are populating the information in the MAUDE database and to evaluate the quality of the data and information submitted.Using FDA MAUDE downloadable data files, 83,528 adverse event medical device narrative reports were identified with the product code of KWA (Prosthesis, Hip, Semiconstrained [Metal Uncemented Acetabular Component]) for JJ/DePuy (KWA Text File). These are class 3 devices and devices with known high failure rates. The ASR XL Acetabular hip replacement Systems and Pinnacle fall into this category. This group of implants was chosen because implant failure is associated with elevated cobalt levels. Two additional subfiles were created from Free Text records in the narrative reports containing key words that indicated a chromium or cobalt (CrCo) device and another for key words indicating elevated levels of cobalt or toxicity. These files were then searched for symptoms of systemic cobalt toxicity with Microsoft Excel using key words pertaining to symptom categories of: cognitive/memory loss, tremor, neuropathy, depression, auditory symptoms, visual symptoms, cardiac, and thyroid disease. Reports are submitted to the FDA at the device component level. It was common for multiple reports to be submitted for a single device.It was not possible to differentiate systemic versus local symptoms for adverse event reports in the neuropathy category. This category was not analyzed. The number of adverse event reports in the other categories ranged from 119 to 16 for the JJ/DePuy KWA Text File and 59 to 4 in the file of records having key words indicating potential elevation of CrCo or toxicity. Cardiac, visual, and auditory conditions were most frequently reported. With the possible exception of cardiomyopathy, the numbers of these reports are far below the prevalence expected in the general population of comparable age. The content of the MAUDE database records often contained little objective data. We found less than 4% of 14,714 records, which indicated cobalt elevation or toxicity contained units for quantitative measurement. There was also frequent use of nondescript, all-encompassing words and phrases such as "mental anguish," found in 321 KWA Text File records. Manufacturers submitted more than 99% of the reports and the most common reporter occupation was attorney, found in 42.24% of the 83,550 JJ/DePuy KWA Reporter File records. Physician was the reporter's occupation in 20.48% of reports but seldom reported directly to the FDA.We were not able find in the FDA MAUDE database meaningful warning signs to support the contention that chromium-cobalt-containing Class 3 JJ and DePuy hip implants caused systemic neurological or thyroid symptoms in patients. The incidence of reported cardiomyopathy was rare but frequent enough to be cause of concern. The redaction of most patient data along with the nonstructured nature of data entry would be expected to hinder the identification of warning signs. Even identification of the type of device could not be consistently carried out. In addition, the FDA needs to implement a methodology to identify and group all reports from a single device implanted into a patient, so duplication of event counting would not occur. Of 83,550 JJ/DePuy KWA Reporter File records, we found only two physician reports sent directly to the FDA. Almost all reports are submitted by manufacturers and are most commonly authored by attorneys. A standard of care needs to be set for physicians to report medical device adverse events to the FDA.

Cobalt (Co) metal is a gray, ductile, magnetic element with an atomic number of 27 and an atomic weight of 58.9 Da. In the environment, cobalt is a component of naturally occurring minerals and is found in combination with other elements such as copper, nickel, manganese, arsenic, sulfur, and oxygen. Due to its ferromagnetic properties, high melting point (1495.05 C), and high boiling point (2927 C), cobalt is widely used in industry to produce hard metals and superalloys. For example, the alloy Alnico is a blend of iron, aluminum, nickel, and cobalt used for its permanent magnetic properties. A common source of chronic cobalt exposure is in the production of tungsten carbide, which is used for its hardness, heat resistance, and strength.  Historically, cobalt chloride (CoCl2) has been used in medicine as a treatment for anemia due to its ability to promote erythropoiesis. However, due to its adverse effects of thyroid dysfunction and the development of goiters, the use of cobalt in treating anemia has fallen out of favor. A biochemically important cobalt compound is cyanocobalamin (vitamin B12) which contains a Co3+-ion. Vitamin B12 is an essential nutrient naturally found in foods of animal origin, such as dairy, eggs, fish, poultry, and meat. Deficiencies in vitamin B12 may lead to pernicious anemia as well as peripheral neuropathy. The precursor hydroxocobalamin is used as an antidote for cyanide poisoning and may have a role in treating vasoplegic shock. Potential cobalt exposure can occur via oral, respiratory, and dermal routes., (Copyright © 2022, StatPearls Publishing LLC.)

Nanoparticle‐based magnetic hyperthermia is a well‐known thermal therapy platform studied to treat solid tumors, but its use for monotherapy is limited due to incomplete tumor eradication at hyperthermia temperature (45 °C). It is often combined with chemotherapy for obtaining a more effective therapeutic outcome. Cubic‐shaped cobalt ferrite nanoparticles (Co–Fe NCs) serve as magnetic hyperthermia agents and as a cytotoxic agent due to the known cobalt ion toxicity, allowing the achievement of both heat and cytotoxic effects from a single platform. In addition to this advantage, Co–Fe NCs have the unique ability to form growing chains under an alternating magnetic field (AMF). This unique chain formation, along with the mild hyperthermia and intrinsic cobalt toxicity, leads to complete tumor regression and improved overall survival in an in vivo murine xenograft model, all under clinically approved AMF conditions. Numerical calculations identify magnetic anisotropy as the main Co–Fe NCs’ feature to generate such chain formations. This novel combination therapy can improve the effects of magnetic hyperthermia, inaugurating investigation of mechanical behaviors of nanoparticles under AMF, as a new avenue for cancer therapy This work was partially funded by the European Research Council (starting grant ICARO, Contract No. 678109) and partially by the AIRC project (Contract No. 14527). The authors also acknowledge Centro de Supercomputación de Galicia (CESGA) for the computational resources. D.S. acknowledges Xunta de Galicia for financial support under the I2C Plan and the Strategic Grouping in Materials (AeMAT; Grant No. ED431E2018/08). This work made use of computational facilities funded by the Small items of research equipment at the University of York ENERGY (Grant No. EP/K031589/1) SI