Monitoring metallic prosthetic implant wear and local tissue destruction in failed hip arthroplasty constructs
This test is not useful for assessment of nutritional status or potential cobalt toxicity.
Inductively Coupled Plasma-Mass Spectrometry (ICP-MS)
Cobalt (Co)
Co (Cobalt)
Synovial Fluid
This test should only be used in individuals with metallic prosthetic implants. The significance of cobalt concentrations in synovial fluid in patients without implants is unknown.
Patient Preparation: High concentrations of gadolinium and iodine are known to interfere with most inductively coupled plasma mass spectrometry-based metal tests. If either gadolinium- or iodine-containing contrast media has been administered, a specimen should not be collected for at least 96 hours.
Supplies: Metal Free B-D Tube (EDTA), 6 mL (T183)
Container/Tube: Royal blue top (metal-free EDTA)
Specimen Volume: 1 mL
Collection Instructions: See Metals Analysis Specimen Collection and Transport for complete instructions.
Additional Information: Cobalt is present in the black rubber plunger seals found in most disposable syringes. As a result, synovial fluid should not be collected in these devices as contamination may occur.
0.4 mL
Gross hemolysis | OK |
Gross lipemia | OK |
Gross icterus | OK |
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Synovial Fluid | Refrigerated (preferred) | 90 days | |
Ambient | 90 days | ||
Frozen | 90 days |
Monitoring metallic prosthetic implant wear and local tissue destruction in failed hip arthroplasty constructs
This test is not useful for assessment of nutritional status or potential cobalt toxicity.
Per US Food and Drug Administration recommendations, orthopedic surgeons should consider measuring and following serial cobalt concentrations in EDTA anticoagulated whole blood in symptomatic patients with metal-on-metal hip implants as part of their overall clinical evaluation. However, a recent publication(1) has shown synovial fluid measurements were superior to whole blood and serum Cobalt concentrations in predicting local tissue destruction in failed hip arthroplasty constructs.
Prosthetic devices produced by Depuy Company, Dow Corning, Howmedica, LCS, PCA, Osteonics, Richards Company, Tricon, and Whiteside are typically made of chromium, cobalt, and molybdenum. This list of products is incomplete, and these products' compositions change occasionally; see each prostheses' product information for composition details.
Cobalt is a naturally occurring, hard, gray element widely distributed in the environment. It is used to produce alloys in the manufacturing of aircraft engines, cutting tools, and some artificial hip and knee joint prosthesis devices.
Cobalt is an essential cofactor for vitamin B12, which is necessary for neurological function, brain function, and the formation of blood. For most people, food is the largest source of cobalt intake. The greatest environmental exposure occurs in mining processes, cemented tungsten-carbide industry, cobalt powder industry, and alloy production industry.
Cobalt is not highly toxic; however large doses may produce adverse clinical manifestations. Acute symptoms include pulmonary edema, allergy, nausea, vomiting, hemorrhage, and kidney failure. Chronic exposure to cobalt-containing hard metal (dust or fume) can result in a serious lung disease called hard metal lung disease, which is a type of pneumoconiosis (lung fibrosis). Furthermore, inhalation of cobalt particles can cause respiratory sensitization, asthma, shortness of breath, and decreased pulmonary function. Even though the primary route of occupational exposure to cobalt is the respiratory tract, skin contact is also important because dermal exposures to hard metal and cobalt salts can result in significant systemic uptake. Sustained exposures can cause skin sensitization, which may result in eruptions of contact dermatitis. In cases of suspected toxicity, blood, serum, or urine concentrations of cobalt can be checked. Vitamin B12 should be used to assess nutritional status.
0-17 years: Not established
> or =18 years: <19.8 ng/mL
Based on an internal study, synovial fluid cobalt concentrations of 19.8 ng/mL or above were more likely due to a metal reaction (eg, adverse local tissue reaction [ALTR]/adverse reaction to metal debris [ARMD]) versus a nonmetal reaction in patients undergoing metal-on-metal revision (sensitivity of 92.3% and specificity of 96.3%).
This test is intended for monitoring of implant wear and should not be ordered to assess nutritional status or potential cobalt toxicity.
Because this test uses mass spectrometry detection, the radioactive form of cobalt, (60)Co, is not quantified.
Specimen collection procedures for cobalt require special specimen collection tubes, rigorous attention to ultraclean specimen collection and handling procedures, and analysis in an ultraclean facility. Elevated trace element concentrations in the absence of corroborating clinical information do not independently predict prosthesis wear or failure.
1. Houdek MT, Taunton MJ, Wyles CC, Jannetto PJ, Lewallen DG, Berry DJ. Synovial fluid metal ion levels are superior to blood metal ion levels in predicting an adverse local tissue reaction in failed total hip arthroplasty. J Arthroplasty. 2021;36(9):3312-3317.e1. doi:10.1016/j.arth.2021.04.034
2. Eltit F, Assiri A, Garbuz D, et al. Adverse reactions to metal on polyethylene implants: Highly destructive lesions related to elevated concentration of cobalt and chromium in synovial fluid. J Biomed Mater Res A. 2017;105(7):1876-1886. doi:10.1002/jbm.a.36057
3. Lass R, Grubl A, Kolb A, et al. Comparison of synovial fluid, urine, and serum ion levels in metal-on-metal total hip arthroplasty at minimum follow-up of 18 years. J Orthop Res. 2014;32(9):1234-1240. doi:10.1002/jor.22652
4. De Pasquale D, Stea S, Squarzoni S, et al. Metal-on-metal hip prostheses: Correlation between debris in the synovial fluid and levels of cobalt and chromium ions in the bloodstream. Int Orthop. 2014;38(3):469-475. doi:10.1007/s00264-013-2137-5
The metal of interest is analyzed by inductively coupled plasma mass spectrometry.(Unpublished Mayo method)
Friday
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.
83018
Test Id | Test Order Name | Order LOINC Value |
---|---|---|
COSY | Cobalt, Synovial Fl | 23842-8 |
Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
---|---|---|
606352 | Cobalt, Synovial Fl | 23842-8 |