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Jami Mandelin - One of the best experts on this subject based on the ideXlab platform.

  • pseudosynovial fluid from loosened total Hip Prosthesis induces osteoclast formation
    Journal of Biomedical Materials Research Part B, 2005
    Co-Authors: Jami Mandelin, Mikko Liljestrom, Tianfang Li, Mari Ainola, Mika Hukkanen, Jari Salo, Seppo Santavirta, Yrjo T Konttinen
    Abstract:

    Interface tissue between the bone and loosening total Hip implant is acidic and highly osteolytic. It is characterized by the formation of cathepsin K positive foreign body giant cells. Similar structures to those found in the normal joint surround the artificial Hip joint. Cells in synovial membrane of the artificial Hip generate synovial fluid that is called pseudosynovial fluid. Interface tissue fibroblasts are able to produce receptor activator of NF-B ligand (RANKL), which can induce osteoclastogenesis during the loosening process. Western blot analysis indicated that RANKL is present in the pseudosynovial fluid. Pseudo- synovial fluid induced cultured peripheral blood mononuclear cells to form multinuclear TRAP positive giant cells. In the presence of osteoprotegerin, the soluble RANKL decoy receptor, the number of TRAP positive multinuclear cells was reduced to half (p < 0.05). The multinuclear cells induced with pseudosynovial fluid contained active cathepsin K protein and were capable of bone matrix resorption in vitro. The cells were shown to express osteoclast phenotype markers, such as mRNA for cathepsin K, TRAP, and calcitonin receptor. It is therefore apparent that pseudosynovial fluid from patients with aseptic loosening of total Hip Prosthesis contains a potent osteoclastogenic factor RANKL that further suggests a favorable environment for osteoclast formation in the peri-implant tissues. It is thus concluded that suppression of RANKL activity may be beneficial in terms of increasing the lifetime of total Hip prostheses. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 74B: 582-588, 2005

  • pseudosynovial fluid from loosened total Hip Prosthesis induces osteoclast formation
    Journal of Biomedical Materials Research, 2005
    Co-Authors: Jami Mandelin, Mikko Liljestrom, Tianfang Li, Mari Ainola, Mika Hukkanen, Jari Salo, Seppo Santavirta, Yrjo T Konttinen
    Abstract:

    Interface tissue between the bone and loosening total Hip implant is acidic and highly osteolytic. It is characterized by the formation of cathepsin K positive foreign body giant cells. Similar structures to those found in the normal joint surround the artificial Hip joint. Cells in synovial membrane of the artificial Hip generate synovial fluid that is called pseudosynovial fluid. Interface tissue fibroblasts are able to produce receptor activator of NF-KB ligand (RANKL), which can induce osteoclastogenesis during the loosening process. Western blot analysis indicated that RANKL is present in the pseudosynovial fluid. Pseudosynovial fluid induced cultured peripheral blood mononuclear cells to form multinuclear TRAP positive giant cells. In the presence of osteoprotegerin, the soluble RANKL decoy receptor, the number of TRAP positive multinuclear cells was reduced to half (p < 0.05). The multinuclear cells induced with pseudosynovial fluid contained active cathepsin K protein and were capable of bone matrix resorption in vitro. The cells were shown to express osteoclast phenotype markers, such as mRNA for cathepsin K, TRAP, and calcitonin receptor. It is therefore apparent that pseudosynovial fluid from patients with aseptic loosening of total Hip Prosthesis contains a potent osteoclastogenic factor RANKL that further suggests a favorable environment for osteoclast formation in the peri-implant tissues. It is thus concluded that suppression of RANKL activity may be beneficial in terms of increasing the lifetime of total Hip prostheses.

Yrjo T Konttinen - One of the best experts on this subject based on the ideXlab platform.

  • pseudosynovial fluid from loosened total Hip Prosthesis induces osteoclast formation
    Journal of Biomedical Materials Research Part B, 2005
    Co-Authors: Jami Mandelin, Mikko Liljestrom, Tianfang Li, Mari Ainola, Mika Hukkanen, Jari Salo, Seppo Santavirta, Yrjo T Konttinen
    Abstract:

    Interface tissue between the bone and loosening total Hip implant is acidic and highly osteolytic. It is characterized by the formation of cathepsin K positive foreign body giant cells. Similar structures to those found in the normal joint surround the artificial Hip joint. Cells in synovial membrane of the artificial Hip generate synovial fluid that is called pseudosynovial fluid. Interface tissue fibroblasts are able to produce receptor activator of NF-B ligand (RANKL), which can induce osteoclastogenesis during the loosening process. Western blot analysis indicated that RANKL is present in the pseudosynovial fluid. Pseudo- synovial fluid induced cultured peripheral blood mononuclear cells to form multinuclear TRAP positive giant cells. In the presence of osteoprotegerin, the soluble RANKL decoy receptor, the number of TRAP positive multinuclear cells was reduced to half (p < 0.05). The multinuclear cells induced with pseudosynovial fluid contained active cathepsin K protein and were capable of bone matrix resorption in vitro. The cells were shown to express osteoclast phenotype markers, such as mRNA for cathepsin K, TRAP, and calcitonin receptor. It is therefore apparent that pseudosynovial fluid from patients with aseptic loosening of total Hip Prosthesis contains a potent osteoclastogenic factor RANKL that further suggests a favorable environment for osteoclast formation in the peri-implant tissues. It is thus concluded that suppression of RANKL activity may be beneficial in terms of increasing the lifetime of total Hip prostheses. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 74B: 582-588, 2005

  • pseudosynovial fluid from loosened total Hip Prosthesis induces osteoclast formation
    Journal of Biomedical Materials Research, 2005
    Co-Authors: Jami Mandelin, Mikko Liljestrom, Tianfang Li, Mari Ainola, Mika Hukkanen, Jari Salo, Seppo Santavirta, Yrjo T Konttinen
    Abstract:

    Interface tissue between the bone and loosening total Hip implant is acidic and highly osteolytic. It is characterized by the formation of cathepsin K positive foreign body giant cells. Similar structures to those found in the normal joint surround the artificial Hip joint. Cells in synovial membrane of the artificial Hip generate synovial fluid that is called pseudosynovial fluid. Interface tissue fibroblasts are able to produce receptor activator of NF-KB ligand (RANKL), which can induce osteoclastogenesis during the loosening process. Western blot analysis indicated that RANKL is present in the pseudosynovial fluid. Pseudosynovial fluid induced cultured peripheral blood mononuclear cells to form multinuclear TRAP positive giant cells. In the presence of osteoprotegerin, the soluble RANKL decoy receptor, the number of TRAP positive multinuclear cells was reduced to half (p < 0.05). The multinuclear cells induced with pseudosynovial fluid contained active cathepsin K protein and were capable of bone matrix resorption in vitro. The cells were shown to express osteoclast phenotype markers, such as mRNA for cathepsin K, TRAP, and calcitonin receptor. It is therefore apparent that pseudosynovial fluid from patients with aseptic loosening of total Hip Prosthesis contains a potent osteoclastogenic factor RANKL that further suggests a favorable environment for osteoclast formation in the peri-implant tissues. It is thus concluded that suppression of RANKL activity may be beneficial in terms of increasing the lifetime of total Hip prostheses.

Mikko Liljestrom - One of the best experts on this subject based on the ideXlab platform.

  • pseudosynovial fluid from loosened total Hip Prosthesis induces osteoclast formation
    Journal of Biomedical Materials Research Part B, 2005
    Co-Authors: Jami Mandelin, Mikko Liljestrom, Tianfang Li, Mari Ainola, Mika Hukkanen, Jari Salo, Seppo Santavirta, Yrjo T Konttinen
    Abstract:

    Interface tissue between the bone and loosening total Hip implant is acidic and highly osteolytic. It is characterized by the formation of cathepsin K positive foreign body giant cells. Similar structures to those found in the normal joint surround the artificial Hip joint. Cells in synovial membrane of the artificial Hip generate synovial fluid that is called pseudosynovial fluid. Interface tissue fibroblasts are able to produce receptor activator of NF-B ligand (RANKL), which can induce osteoclastogenesis during the loosening process. Western blot analysis indicated that RANKL is present in the pseudosynovial fluid. Pseudo- synovial fluid induced cultured peripheral blood mononuclear cells to form multinuclear TRAP positive giant cells. In the presence of osteoprotegerin, the soluble RANKL decoy receptor, the number of TRAP positive multinuclear cells was reduced to half (p < 0.05). The multinuclear cells induced with pseudosynovial fluid contained active cathepsin K protein and were capable of bone matrix resorption in vitro. The cells were shown to express osteoclast phenotype markers, such as mRNA for cathepsin K, TRAP, and calcitonin receptor. It is therefore apparent that pseudosynovial fluid from patients with aseptic loosening of total Hip Prosthesis contains a potent osteoclastogenic factor RANKL that further suggests a favorable environment for osteoclast formation in the peri-implant tissues. It is thus concluded that suppression of RANKL activity may be beneficial in terms of increasing the lifetime of total Hip prostheses. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 74B: 582-588, 2005

  • pseudosynovial fluid from loosened total Hip Prosthesis induces osteoclast formation
    Journal of Biomedical Materials Research, 2005
    Co-Authors: Jami Mandelin, Mikko Liljestrom, Tianfang Li, Mari Ainola, Mika Hukkanen, Jari Salo, Seppo Santavirta, Yrjo T Konttinen
    Abstract:

    Interface tissue between the bone and loosening total Hip implant is acidic and highly osteolytic. It is characterized by the formation of cathepsin K positive foreign body giant cells. Similar structures to those found in the normal joint surround the artificial Hip joint. Cells in synovial membrane of the artificial Hip generate synovial fluid that is called pseudosynovial fluid. Interface tissue fibroblasts are able to produce receptor activator of NF-KB ligand (RANKL), which can induce osteoclastogenesis during the loosening process. Western blot analysis indicated that RANKL is present in the pseudosynovial fluid. Pseudosynovial fluid induced cultured peripheral blood mononuclear cells to form multinuclear TRAP positive giant cells. In the presence of osteoprotegerin, the soluble RANKL decoy receptor, the number of TRAP positive multinuclear cells was reduced to half (p < 0.05). The multinuclear cells induced with pseudosynovial fluid contained active cathepsin K protein and were capable of bone matrix resorption in vitro. The cells were shown to express osteoclast phenotype markers, such as mRNA for cathepsin K, TRAP, and calcitonin receptor. It is therefore apparent that pseudosynovial fluid from patients with aseptic loosening of total Hip Prosthesis contains a potent osteoclastogenic factor RANKL that further suggests a favorable environment for osteoclast formation in the peri-implant tissues. It is thus concluded that suppression of RANKL activity may be beneficial in terms of increasing the lifetime of total Hip prostheses.

John S Xenos - One of the best experts on this subject based on the ideXlab platform.

  • the porous coated anatomic total Hip Prosthesis inserted without cement a prospective study with a minimum ten years of follow up
    Journal of Bone and Joint Surgery American Volume, 1999
    Co-Authors: John S Xenos, John J Callaghan, R D Heekin, C G Savory, William Hopkinson, Milan S Moore
    Abstract:

    One hundred consecutive primary total Hip arthroplasties performed with use of a porous-coated anatomic total Hip Prosthesis, fixed without cement, in ninety-one patients were followed prospectively for a minimum of ten years. At the time of the most recent follow-up, twenty patients (twenty-three Hips) had died and seventy-one patients (seventy-seven Hips) were living. The average age of the living patients was sixty-six years (range, thirty-two to ninety-two years), and their average Harris Hip score was 84 points (range, 33 to 100 points). Twelve percent (nine) of the seventy-seven Hips were found to be associated with pain in the thigh when the patients were specifically questioned by the examiner. Eleven Hips were revised during the follow-up period. Only the acetabular component was revised in six Hips, only the femoral component was revised in one Hip, and both the femoral and the acetabular components were revised in four Hips. Of the ten acetabular revisions, one was performed because of acute dissociation of the component and eight, because of a combination of polyethylene wear, osteolysis, and loosening; the tenth acetabular revision consisted of exchange of the liner and curettage and bone-grafting of the osteolytic area. Of the five femoral revisions, two were performed because of loosening and three, because of extensive osteolysis of the proximal aspect of the femur. Including the revised components, twelve acetabular components and five femoral components had radiographic evidence of aseptic loosening. Acetabular osteolysis occurred in seventeen Hips. Femoral osteolysis occurred in thirty-nine Hips: in the proximal aspect of thirty-one Hips, in the distal aspect of four, and in both the proximal and the distal aspect of four. The durability of the femoral fixation documented in this study is especially encouraging in view of the fact that this was our initial experience with devices fixed without cement and that a so-called first-generation femoral component was used. However, the study also demonstrated that not all acetabular components fixed without cement function well over the long term and that specific design considerations (adequate initial fixation, congruency between the liner and the shell, an optimum shell-liner capturing mechanism, and a smaller femoral head) are warranted.

  • the porous coated anatomic total Hip Prosthesis inserted without cement results after five to seven years in a prospective study
    Journal of Bone and Joint Surgery American Volume, 1993
    Co-Authors: R D Heekin, J J Callaghan, W J Hopkinson, C G Savory, John S Xenos
    Abstract:

    The results of 100 primary arthroplasties with a porous-coated anatomic total Hip Prosthesis that were performed consecutively in ninety-one patients were followed prospectively for five to seven years after the operation or until death. Clinical Harris Hip ratings and anteroposterior and lateral radiographs were made preoperatively, several times in the first postoperative year, and at annual intervals thereafter. Average sequential Hip ratings were maintained between 92 and 93 points during the follow-up interval. Pain in the thigh, which did not limit function, was recorded at the yearly examinations from the first to the fifth year. After one year, 18 per cent of the thighs were painful, and in succeeding years, 19 per cent, 23 per cent, 26 per cent, and 15 per cent were painful. Radiographs demonstrated that the fixation of the femoral component was by ingrowth of bone in 94 per cent of the Hips, by stable fibrous fixation in 1 per cent, and by unstable fibrous fixation in 5 per cent, according to the criteria of Engh et al. By five years, 6 per cent of the acetabular components had migrated, and 5 per cent of the femoral components had subsided. Two acetabular components had been revised, and one revision of a femoral component was pending. The evaluated device was an early-generation Prosthesis that was designed for insertion without the use of cement. Further study is necessary to determine the long-term durability of the Prosthesis-bone interface.

Shing-sheng Wu - One of the best experts on this subject based on the ideXlab platform.

  • disassembly and dislocation of a bipolar Hip Prosthesis
    Journal of the Formosan Medical Association, 2008
    Co-Authors: Yung Chih Lo, Shing-sheng Wu
    Abstract:

    Dislocation of a Hip Prosthesis is a common complication. In usual cases of Hip Prosthesis dislocation, the prosthetic femoral head comes out from either the natural acetabular cavity in a bipolar hemiarthroplasty or the prosthetic acetabulum in a total Hip arthroplasty. Only a few cases of bipolar Hip Prosthesis dislocation due to dissociation between the polyethylene and inner head of the Prosthesis have been reported. We describe a rare case of disassembly of the inner head from the bipolar outer Prosthesis in an osteoarthritic acetabulum. A 72-year-old woman had undergone bipolar hemiarthroplasty due to fracture of the left femoral neck about 10 years previously. Recently, she sustained an injury after falling from a chair, and examinations revealed an unusual disassembly−dislocation of the bipolar Hip Prosthesis. We classified this failure in our patient as a type II failure, representing extreme varus position of the outer head in the acetabulum, dislocation of the inner head from the outer head, and a detached locking ring around the stem neck. This mechanism of failure as shown in our patient rarely occurs in the bipolar Prosthesis of the self-centering system. Osteoarthritic change of the acetabulum would place the outer head in the varus position, increasing wear on the beveled rim by impinging the femoral stem neck and causing dislodgment of the inner locking ring and consequent disassembly−dislocation of the inner head.