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Antti Eskelinen - One of the best experts on this subject based on the ideXlab platform.
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association between periprosthetic tissue metal content whole blood and synovial fluid metal ion levels and histopathological findings in patients with failed metal on metal hip replacement
PLOS ONE, 2018Co-Authors: Lari Lehtovirta, Aleksi Reito, Jyrki Parkkinen, Sirpa Peraniemi, Jouko Vepsalainen, Antti EskelinenAbstract:Adverse Reaction to Metal Debris (ARMD) is a major cause of implant failure leading to revision surgery in patients with metal-on-metal (MoM) hip arthroplasties. However, the pathogenesis and its association to implant Wear are poorly understood and previous studies have yielded discrepant results. We sought to investigate the associations between histological findings, whole blood and synovial fluid metal ion concentrations and periprosthetic tissue metal concentrations in patients with MoM total hip replacements and hip resurfacings revised for ARMD. 107 hips in total were included in our study. Of these, 87 were total hip replacements and 20 were hip resurfacings, respectively. We found that whole blood, synovial fluid and periprosthetic tissue metal concentrations correlated poorly with histological findings. We suggest that the lack of a clear association between histological findings and Wear measures in the present study as well as in previous studies is mostly influenced by variability in patient susceptibility. However, patients presenting with perivascular lymphocytic infiltration had lower chromium concentration in their periprosthetic tissues than patients with no perivascular lymphocytic infiltration. This may reflect the role of metal hypersensitivity in implant failure in these patients. Patients with total hip replacements evinced more necrosis and lymphocytic infiltration in their tissues than patients with hip resurfacings. This suggests that trunnion Wear debris is more cytotoxic and/or immunogenic than Bearing Wear debris leading to higher failure rates seen in patients with total hip replacements.
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analysis of Bearing Wear whole blood and synovial fluid metal ion concentrations and histopathological findings in patients with failed asr hip resurfacings
BMC Musculoskeletal Disorders, 2017Co-Authors: Lari Lehtovirta, Aleksi Reito, Jyrki Parkkinen, Harry Hothi, Johann Henckel, Allister Hart, Antti EskelinenAbstract:Adverse Reaction to Metal Debris (ARMD) is still a major reason for revision surgeries in patients with metal-on-metal (MoM) hip replacements. ARMD consists of a wide range of alterations in periprosthetic tissues, most important of which are metallosis, inflammation, pseudotumors and necrosis. Studies investigating histopathological findings and their association to implant Wear or indirect measures of Wear have yielded inconsistent results. Therefore, we aimed to investigate Bearing surface Wear volume, whole blood and synovial fluid metal ion concentrations, histopathological findings in periprosthetic tissues and their associations. Seventy-eight patients with 85 hips revised for ARMD were included in the study. Prior to revision surgery, all patients had whole blood chromium and cobalt ion levels assessed. In revision surgery, a synovial fluid sample was taken and analyzed for chromium and cobalt. Periprosthetic tissue samples were taken and analyzed for histopathological findings. Explanted implants were analyzed for Bearing Wear volume of both acetabular cup and femoral head components. Volumetric Wear of the failed components was highly variable. The total Wear volume of the head and cup had a strong correlation with whole blood chromium and cobalt ion concentrations (Cr: ρ = 0.80, p < 0.001 and Co: ρ = 0.84, p < 0.001) and a bit weaker correlation with fluid chromium and cobalt ion concentrations (Cr: ρ = 0.50, p < 0.01 and Co: ρ = 0.41, p = 0.027). Most tissues displayed only low-to-moderate amounts of macrophages and lymphocytes. Total Wear volume correlated with macrophage sheet thickness (ρ = 0.25, p = 0.020) and necrosis (ρ = 0.35, p < 0.01). Whole blood chromium and cobalt ion concentrations had similar correlations. Lymphocyte cuff thickness did not correlate with either total Wear volume or whole blood metal ion concentrations, but correlated with the grade of necrosis. Bearing Wear volume correlated with blood metal ion levels and the degree of necrosis and macrophage infiltration in periprosthetic tissues suggesting a dose-response relationship. Whole blood metal ion levels are a useful tool for clinician to estimate Bearing Wear and subsequent tissue response.
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Analysis of Bearing Wear, whole blood and synovial fluid metal ion concentrations and histopathological findings in patients with failed ASR hip resurfacings
BMC, 2017Co-Authors: Lari Lehtovirta, Aleksi Reito, Jyrki Parkkinen, Harry Hothi, Johann Henckel, Alister Hart, Antti EskelinenAbstract:Abstract Background Adverse Reaction to Metal Debris (ARMD) is still a major reason for revision surgeries in patients with metal-on-metal (MoM) hip replacements. ARMD consists of a wide range of alterations in periprosthetic tissues, most important of which are metallosis, inflammation, pseudotumors and necrosis. Studies investigating histopathological findings and their association to implant Wear or indirect measures of Wear have yielded inconsistent results. Therefore, we aimed to investigate Bearing surface Wear volume, whole blood and synovial fluid metal ion concentrations, histopathological findings in periprosthetic tissues and their associations. Methods Seventy-eight patients with 85 hips revised for ARMD were included in the study. Prior to revision surgery, all patients had whole blood chromium and cobalt ion levels assessed. In revision surgery, a synovial fluid sample was taken and analyzed for chromium and cobalt. Periprosthetic tissue samples were taken and analyzed for histopathological findings. Explanted implants were analyzed for Bearing Wear volume of both acetabular cup and femoral head components. Results Volumetric Wear of the failed components was highly variable. The total Wear volume of the head and cup had a strong correlation with whole blood chromium and cobalt ion concentrations (Cr: ρ = 0.80, p
Lari Lehtovirta - One of the best experts on this subject based on the ideXlab platform.
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association between periprosthetic tissue metal content whole blood and synovial fluid metal ion levels and histopathological findings in patients with failed metal on metal hip replacement
PLOS ONE, 2018Co-Authors: Lari Lehtovirta, Aleksi Reito, Jyrki Parkkinen, Sirpa Peraniemi, Jouko Vepsalainen, Antti EskelinenAbstract:Adverse Reaction to Metal Debris (ARMD) is a major cause of implant failure leading to revision surgery in patients with metal-on-metal (MoM) hip arthroplasties. However, the pathogenesis and its association to implant Wear are poorly understood and previous studies have yielded discrepant results. We sought to investigate the associations between histological findings, whole blood and synovial fluid metal ion concentrations and periprosthetic tissue metal concentrations in patients with MoM total hip replacements and hip resurfacings revised for ARMD. 107 hips in total were included in our study. Of these, 87 were total hip replacements and 20 were hip resurfacings, respectively. We found that whole blood, synovial fluid and periprosthetic tissue metal concentrations correlated poorly with histological findings. We suggest that the lack of a clear association between histological findings and Wear measures in the present study as well as in previous studies is mostly influenced by variability in patient susceptibility. However, patients presenting with perivascular lymphocytic infiltration had lower chromium concentration in their periprosthetic tissues than patients with no perivascular lymphocytic infiltration. This may reflect the role of metal hypersensitivity in implant failure in these patients. Patients with total hip replacements evinced more necrosis and lymphocytic infiltration in their tissues than patients with hip resurfacings. This suggests that trunnion Wear debris is more cytotoxic and/or immunogenic than Bearing Wear debris leading to higher failure rates seen in patients with total hip replacements.
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analysis of Bearing Wear whole blood and synovial fluid metal ion concentrations and histopathological findings in patients with failed asr hip resurfacings
BMC Musculoskeletal Disorders, 2017Co-Authors: Lari Lehtovirta, Aleksi Reito, Jyrki Parkkinen, Harry Hothi, Johann Henckel, Allister Hart, Antti EskelinenAbstract:Adverse Reaction to Metal Debris (ARMD) is still a major reason for revision surgeries in patients with metal-on-metal (MoM) hip replacements. ARMD consists of a wide range of alterations in periprosthetic tissues, most important of which are metallosis, inflammation, pseudotumors and necrosis. Studies investigating histopathological findings and their association to implant Wear or indirect measures of Wear have yielded inconsistent results. Therefore, we aimed to investigate Bearing surface Wear volume, whole blood and synovial fluid metal ion concentrations, histopathological findings in periprosthetic tissues and their associations. Seventy-eight patients with 85 hips revised for ARMD were included in the study. Prior to revision surgery, all patients had whole blood chromium and cobalt ion levels assessed. In revision surgery, a synovial fluid sample was taken and analyzed for chromium and cobalt. Periprosthetic tissue samples were taken and analyzed for histopathological findings. Explanted implants were analyzed for Bearing Wear volume of both acetabular cup and femoral head components. Volumetric Wear of the failed components was highly variable. The total Wear volume of the head and cup had a strong correlation with whole blood chromium and cobalt ion concentrations (Cr: ρ = 0.80, p < 0.001 and Co: ρ = 0.84, p < 0.001) and a bit weaker correlation with fluid chromium and cobalt ion concentrations (Cr: ρ = 0.50, p < 0.01 and Co: ρ = 0.41, p = 0.027). Most tissues displayed only low-to-moderate amounts of macrophages and lymphocytes. Total Wear volume correlated with macrophage sheet thickness (ρ = 0.25, p = 0.020) and necrosis (ρ = 0.35, p < 0.01). Whole blood chromium and cobalt ion concentrations had similar correlations. Lymphocyte cuff thickness did not correlate with either total Wear volume or whole blood metal ion concentrations, but correlated with the grade of necrosis. Bearing Wear volume correlated with blood metal ion levels and the degree of necrosis and macrophage infiltration in periprosthetic tissues suggesting a dose-response relationship. Whole blood metal ion levels are a useful tool for clinician to estimate Bearing Wear and subsequent tissue response.
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Analysis of Bearing Wear, whole blood and synovial fluid metal ion concentrations and histopathological findings in patients with failed ASR hip resurfacings
BMC, 2017Co-Authors: Lari Lehtovirta, Aleksi Reito, Jyrki Parkkinen, Harry Hothi, Johann Henckel, Alister Hart, Antti EskelinenAbstract:Abstract Background Adverse Reaction to Metal Debris (ARMD) is still a major reason for revision surgeries in patients with metal-on-metal (MoM) hip replacements. ARMD consists of a wide range of alterations in periprosthetic tissues, most important of which are metallosis, inflammation, pseudotumors and necrosis. Studies investigating histopathological findings and their association to implant Wear or indirect measures of Wear have yielded inconsistent results. Therefore, we aimed to investigate Bearing surface Wear volume, whole blood and synovial fluid metal ion concentrations, histopathological findings in periprosthetic tissues and their associations. Methods Seventy-eight patients with 85 hips revised for ARMD were included in the study. Prior to revision surgery, all patients had whole blood chromium and cobalt ion levels assessed. In revision surgery, a synovial fluid sample was taken and analyzed for chromium and cobalt. Periprosthetic tissue samples were taken and analyzed for histopathological findings. Explanted implants were analyzed for Bearing Wear volume of both acetabular cup and femoral head components. Results Volumetric Wear of the failed components was highly variable. The total Wear volume of the head and cup had a strong correlation with whole blood chromium and cobalt ion concentrations (Cr: ρ = 0.80, p
J N Lawton - One of the best experts on this subject based on the ideXlab platform.
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Bearing component response to physiologic loading in three common total elbow replacement systems
Orthopaedic Proceedings, 2018Co-Authors: Philippe Favre, E A King, M Palmer, Amin Eldemerdash, J Bischoff, J N LawtonAbstract:INTRODUCTIONAseptic loosening is the most common failure mode for Total Elbow Arthroplasty (TEA) and is considered to be associated with accelerated polyethylene Bearing Wear [1, 2]. This study aimed to evaluate three commercially available implant designs under loads associated with daily living. The hypothesis was that more recent designs (Discovery and Nexel) provide greater articular contact areas resulting in lower polyethylene stresses compared to the Coonrad/Morrey (CM).METHODSMotion tracking was performed on a healthy volunteer during elbow flexion at 0, 45, and 90° shoulder abduction because most daily activities occur with some shoulder abduction [3] resulting in varus stress about the elbow. This kinematic data was used in an OpenSim upper extremity musculoskeletal model [4] to estimate muscle and joint reaction loads with 5lb in hand, consistent with the common clinical restrictions following TEA.Computer aided assemblies of the smallest size implants for each system were imported to ANSYS for...
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Bearing component response to physiologic loading in three common total elbow replacement systems
Journal of Bone and Joint Surgery-british Volume, 2017Co-Authors: Philippe Favre, E A King, M Palmer, Amin Eldemerdash, J Bischoff, J N LawtonAbstract:INTRODUCTION Aseptic loosening is the most common failure mode for Total Elbow Arthroplasty (TEA) and is considered to be associated with accelerated polyethylene Bearing Wear [1, 2]. This study aimed to evaluate three commercially available implant designs under loads associated with daily living. The hypothesis was that more recent designs (Discovery and Nexel) provide greater articular contact areas resulting in lower polyethylene stresses compared to the Coonrad/Morrey (CM). METHODS Motion tracking was performed on a healthy volunteer during elbow flexion at 0, 45, and 90° shoulder abduction because most daily activities occur with some shoulder abduction [3] resulting in varus stress about the elbow. This kinematic data was used in an OpenSim upper extremity musculoskeletal model [4] to estimate muscle and joint reaction loads with 5lb in hand, consistent with the common clinical restrictions following TEA. Computer aided assemblies of the smallest size implants for each system were imported to ANSYS for finite element analysis. Metallic components were treated as rigid and polyethylene components were modeled using a nonlinear elastoplastic constitutive model calibrated to material data. Articular contacts were frictional. Physiologic joint reaction forces and moments quantified in OpenSim were applied and the resulting peak articular contact area and peak Bearing von Mises stresses were assessed. RESULTS Simulated deformation patterns of CM Bearings corresponded well to those reported in retrievals studies [1, 2] supporting the clinical relevance of the modeling approach. Peak stresses for CM and Nexel were consistently found in the central and side Bearings respectively. The central Bearing stresses remained 2–2.6 times lower in Nexel compared to CM. Peak stress for all three TEA systems increased with shoulder abduction (Fig.1, 2). Highest peak stresses (Fig.2) were obtained in CM and consistently exceeded the polyethylene yield limit; CM showed the lowest contact area (Fig.3). Nexel and Discovery experienced peak polyethylene stresses 26–34% and 17–39% lower than CM respectively (Fig.2). DISCUSSION Our results support the hypothesis that newer TEA systems provide increased articular contact area and reduced Bearing stresses during physiological loading. The cylindrical CM central Bearing carries both the joint reaction force and moment leading to edge loading and high stresses (Fig.1). The design of the Nexel central Bearing provides limited resistance to varus-valgus moment, thus transferring the moment to the side Bearings and reducing central Bearing stresses. The hemispherical Discovery Bearing design was confirmed to offer a large articular contact area. However, non-concentricity of the contact spheres can lead to edge loading and high polyethylene stresses under off-axis forces. CM and Discovery utilize conventional polyethylene, whereas Nexel utilizes highly cross-linked Vitamin-E polyethylene. This study does not account for the increased Wear resistance of Vitamin-E as compared to conventional polyethylene [5]. Long term clinical data are needed to demonstrate how these Wear properties, as well as the geometric design which has been shown to impact stresses and contact patterns, translate to in vivo performance. For figures, please contact authors directly
Jim Nevelos - One of the best experts on this subject based on the ideXlab platform.
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increased Wear in low and high crosslinked polyethylene due to microseparation of total hip arthroplasty components
Journal of Bone and Joint Surgery-british Volume, 2013Co-Authors: Darryl D Dlima, Jonathan Netter, Juan C Hermida, Peter C Chen, Nikolai Steklov, Jim NevelosAbstract:Introduction: Microseparation has resulted in more than ten-fold increase in ceramic-on-ceramic and metal-on-metal Bearing Wear, and even fracture in a zirconia head [1–4]. However, despite the greater microseparation reported clinically for metal-on-polyethylene Wear, less is known about its potential detrimental effects for this Bearing couple. This study was therefore designed to simulate the effects of micromotion using finite element analysis and to validate computational predictions with experimental Wear testing. Methods: Experimental Wear rates for low and highly crosslinked polyethylene hip liners were obtained from a previously reported conventional hip Wear simulator study [5]. A finite element model of the Wear simulation for this design was constructed to replicate experimental conditions and to compute the Wear coefficients that matched the experimental Wear rates. We have previous described out this method of validation for knee Wear simulation studies [6,7]. This Wear coefficient was used to predict Wear in a Dual-Mobility hip component (Fig 1). Dual mobility total hip arthroplasty components, Restoration ADM (Fig 1), with highly crosslinked acetabular liners were experimentally tested: the control group was subjected to Wear testing using the ISO 14242-1 waveform on a hip Wear simulator. The microseparation group was subjected to a nominal 0.8 mm lateral microseparation during the swing phase by engaging lateral force springs and reducing the swing phase vertical force. Results: The Wear coefficients that matched experimental Wear rates for the low and highly crosslinked polyethylene liners were 4.57×10 −10 and 5.89×10 −11 mm 3 N −1 mm −1 , respectively. Introducing microseparation in the conventional hip increased the Wear rate by 15.59 mm 3 /million cycles in the low crosslinked liner and by 1.12 mm 3 /million cycles in the highly crosslinked liner (Fig 2). Discussion: Microseparation did increase predicted Wear rates for the low crosslinked polyethylene liner and supports the hypothesis that microseparation can adversely affect the Wear of hip arthroplasty. However, the predicted and experimental increase for the dual mobility highly crosslinked liners due to microseparation was low (3.3 mm 3 and 2.9 mm 3 /million cycles, respectively) and below the threshold for clinical relevance. The small increase in Wear rate in our study supports the high Wear tolerance to Wear of a dual-mobility sequentially crosslinked polyethylene liner.
Jyrki Parkkinen - One of the best experts on this subject based on the ideXlab platform.
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association between periprosthetic tissue metal content whole blood and synovial fluid metal ion levels and histopathological findings in patients with failed metal on metal hip replacement
PLOS ONE, 2018Co-Authors: Lari Lehtovirta, Aleksi Reito, Jyrki Parkkinen, Sirpa Peraniemi, Jouko Vepsalainen, Antti EskelinenAbstract:Adverse Reaction to Metal Debris (ARMD) is a major cause of implant failure leading to revision surgery in patients with metal-on-metal (MoM) hip arthroplasties. However, the pathogenesis and its association to implant Wear are poorly understood and previous studies have yielded discrepant results. We sought to investigate the associations between histological findings, whole blood and synovial fluid metal ion concentrations and periprosthetic tissue metal concentrations in patients with MoM total hip replacements and hip resurfacings revised for ARMD. 107 hips in total were included in our study. Of these, 87 were total hip replacements and 20 were hip resurfacings, respectively. We found that whole blood, synovial fluid and periprosthetic tissue metal concentrations correlated poorly with histological findings. We suggest that the lack of a clear association between histological findings and Wear measures in the present study as well as in previous studies is mostly influenced by variability in patient susceptibility. However, patients presenting with perivascular lymphocytic infiltration had lower chromium concentration in their periprosthetic tissues than patients with no perivascular lymphocytic infiltration. This may reflect the role of metal hypersensitivity in implant failure in these patients. Patients with total hip replacements evinced more necrosis and lymphocytic infiltration in their tissues than patients with hip resurfacings. This suggests that trunnion Wear debris is more cytotoxic and/or immunogenic than Bearing Wear debris leading to higher failure rates seen in patients with total hip replacements.
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analysis of Bearing Wear whole blood and synovial fluid metal ion concentrations and histopathological findings in patients with failed asr hip resurfacings
BMC Musculoskeletal Disorders, 2017Co-Authors: Lari Lehtovirta, Aleksi Reito, Jyrki Parkkinen, Harry Hothi, Johann Henckel, Allister Hart, Antti EskelinenAbstract:Adverse Reaction to Metal Debris (ARMD) is still a major reason for revision surgeries in patients with metal-on-metal (MoM) hip replacements. ARMD consists of a wide range of alterations in periprosthetic tissues, most important of which are metallosis, inflammation, pseudotumors and necrosis. Studies investigating histopathological findings and their association to implant Wear or indirect measures of Wear have yielded inconsistent results. Therefore, we aimed to investigate Bearing surface Wear volume, whole blood and synovial fluid metal ion concentrations, histopathological findings in periprosthetic tissues and their associations. Seventy-eight patients with 85 hips revised for ARMD were included in the study. Prior to revision surgery, all patients had whole blood chromium and cobalt ion levels assessed. In revision surgery, a synovial fluid sample was taken and analyzed for chromium and cobalt. Periprosthetic tissue samples were taken and analyzed for histopathological findings. Explanted implants were analyzed for Bearing Wear volume of both acetabular cup and femoral head components. Volumetric Wear of the failed components was highly variable. The total Wear volume of the head and cup had a strong correlation with whole blood chromium and cobalt ion concentrations (Cr: ρ = 0.80, p < 0.001 and Co: ρ = 0.84, p < 0.001) and a bit weaker correlation with fluid chromium and cobalt ion concentrations (Cr: ρ = 0.50, p < 0.01 and Co: ρ = 0.41, p = 0.027). Most tissues displayed only low-to-moderate amounts of macrophages and lymphocytes. Total Wear volume correlated with macrophage sheet thickness (ρ = 0.25, p = 0.020) and necrosis (ρ = 0.35, p < 0.01). Whole blood chromium and cobalt ion concentrations had similar correlations. Lymphocyte cuff thickness did not correlate with either total Wear volume or whole blood metal ion concentrations, but correlated with the grade of necrosis. Bearing Wear volume correlated with blood metal ion levels and the degree of necrosis and macrophage infiltration in periprosthetic tissues suggesting a dose-response relationship. Whole blood metal ion levels are a useful tool for clinician to estimate Bearing Wear and subsequent tissue response.
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Analysis of Bearing Wear, whole blood and synovial fluid metal ion concentrations and histopathological findings in patients with failed ASR hip resurfacings
BMC, 2017Co-Authors: Lari Lehtovirta, Aleksi Reito, Jyrki Parkkinen, Harry Hothi, Johann Henckel, Alister Hart, Antti EskelinenAbstract:Abstract Background Adverse Reaction to Metal Debris (ARMD) is still a major reason for revision surgeries in patients with metal-on-metal (MoM) hip replacements. ARMD consists of a wide range of alterations in periprosthetic tissues, most important of which are metallosis, inflammation, pseudotumors and necrosis. Studies investigating histopathological findings and their association to implant Wear or indirect measures of Wear have yielded inconsistent results. Therefore, we aimed to investigate Bearing surface Wear volume, whole blood and synovial fluid metal ion concentrations, histopathological findings in periprosthetic tissues and their associations. Methods Seventy-eight patients with 85 hips revised for ARMD were included in the study. Prior to revision surgery, all patients had whole blood chromium and cobalt ion levels assessed. In revision surgery, a synovial fluid sample was taken and analyzed for chromium and cobalt. Periprosthetic tissue samples were taken and analyzed for histopathological findings. Explanted implants were analyzed for Bearing Wear volume of both acetabular cup and femoral head components. Results Volumetric Wear of the failed components was highly variable. The total Wear volume of the head and cup had a strong correlation with whole blood chromium and cobalt ion concentrations (Cr: ρ = 0.80, p