The Experts below are selected from a list of 34176 Experts worldwide ranked by ideXlab platform
Pierrelouis Docquier - One of the best experts on this subject based on the ideXlab platform.
-
improved accuracy with 3d planning and patient specific instruments during simulated pelvic Bone Tumor surgery
Annals of Biomedical Engineering, 2014Co-Authors: Olivier Cartiaux, Laurent Paul, Pierrelouis Docquier, Xavier Banse, Bernard G FrancqAbstract:In orthopaedic surgery, resection of pelvic Bone Tumors can be inaccurate due to complex geometry, limited visibility and restricted working space of the pelvis. The present study investigated accuracy of patient-specific instrumentation (PSI) for Bone-cutting during simulated Tumor surgery within the pelvis. A synthetic pelvic Bone model was imaged using a CT-scanner. The set of images was reconstructed in 3D and resection of a simulated periacetabular Tumor was defined with four target planes (ischium, pubis, anterior ilium, and posterior ilium) with a 10-mm desired safe margin. Patient-specific instruments for Bone-cutting were designed and manufactured using rapid-prototyping technology. Twenty-four surgeons (10 senior and 14 junior) were asked to perform Tumor resection. After cutting, ISO1101 location and flatness parameters, achieved surgical margins and the time were measured. With PSI, the location accuracy of the cut planes with respect to the target planes averaged 1 and 1.2 mm in the anterior and posterior ilium, 2 mm in the pubis and 3.7 mm in the ischium (p < 0.0001). Results in terms of the location of the cut planes and the achieved surgical margins did not reveal any significant difference between senior and junior surgeons (p = 0.2214 and 0.8449, respectively). The maximum differences between the achieved margins and the 10-mm desired safe margin were found in the pubis (3.1 and 5.1 mm for senior and junior surgeons respectively). Of the 24 simulated resection, there was no intralesional Tumor cutting. This study demonstrates that using PSI technology during simulated Bone cuts of the pelvis can provide good cutting accuracy. Compared to a previous report on computer assistance for pelvic Bone cutting, PSI technology clearly demonstrates an equivalent value-added for Bone cutting accuracy than navigation technology. When in vivo validated, PSI technology may improve pelvic Bone Tumor surgery by providing clinically acceptable margins.
-
computer assisted planning and navigation improves cutting accuracy during simulated Bone Tumor surgery of the pelvis
Computer Aided Surgery, 2013Co-Authors: Olivier Cartiaux, Laurent Paul, Xavier Banse, Bernard G Francq, Carleric Aubin, Pierrelouis DocquierAbstract:Background: Resection of Bone Tumors within the pelvis requires good cutting accuracy to achieve satisfactory safe margins. Manually controlled Bone cutting can result in serious errors, especially due to the complex three-dimensional geometry, limited visibility, and restricted working space of the pelvic Bone. This experimental study investigated cutting accuracy during navigated and non-navigated simulated Bone Tumor cutting in the pelvis. Methods: A periacetabular Tumor resection was simulated using a pelvic Bone model. Twenty-three operators (10 senior and 13 junior surgeons) were asked to perform the Tumor cutting, initially according to a freehand procedure and later with the aid of a navigation system. Before cutting, each operator used preoperative planning software to define four target planes around the Tumor with a 10-mm desired safe margin. After cutting, the location and flatness of the cut planes were measured, as well as the achieved surgical margins and the time required for each cutting procedure. Results: The location of the cut planes with respect to the target planes was significantly improved by using the navigated cutting procedure, averaging 2.8 mm as compared to 11.2 mm for the freehand cutting procedure (p < 0.001). There was no intralesional Tumor cutting when using the navigation system. The maximum difference between the achieved margins and the 10-mm desired safe margin was 6.5 mm with the navigated cutting process (compared to 13 mm with the freehand cutting process). Conclusions: Cutting accuracy during simulated Bone cuts of the pelvis can be significantly improved by using a freehand process assisted by a navigation system. When fully validated with complementary in vivo studies, the planning and navigation-guided technologies that have been developed for the present study may improve Bone cutting accuracy during pelvic Tumor resection by providing clinically acceptable margins.
-
computer assisted planning and patient specific instruments for Bone Tumor surgery within the pelvis an experimental study
13th Annual Meeting of the International Society for Computer Assisted Orthopaedic Surgery, 2013Co-Authors: Laurent Paul, Pierrelouis Docquier, Xavier Banse, Olivier CartiauxAbstract:Resecting Bone Tumors within the pelvis is challenging due to the complex geometry, limited visibility and restricted workspace of the pelvic Bone. Tumor resection requires good cutting accuracy to achieve satisfactory margins and avoid the risk of local recurrence. Computer-assisted technologies have been developed for pelvic Bone Tumor surgeries to improve cutting accuracy. Preoperative planning and intraoperative navigation are available for the positioning of surgical tools (chisels, burrs, saws…) [1]: clinical studies already have demonstrated the feasibility of achieving Tumor-free resection margins within the pelvis with the aid of these assistance technologies. Patient-specific instrumentation technology has been developed as an alternative to intraoperative navigation. Commercially available patient-specific instruments exist for total knee arthroplasty [2], pedicle screw insertion [3] and pelvic osteotomy [4]. To date, no studies have reported accuracy data on achieved margins during pelvic Bone Tumor resections with patient-specific instruments. This experimental study investigated the accuracy of patient-specific instrumentation technology for Bone cutting during simulated Tumor surgeries within the pelvis.
-
pelvic reconstruction with a structural pelvic allograft after resection of a malignant Bone Tumor
Journal of Bone and Joint Surgery American Volume, 2007Co-Authors: Christian Delloye, Pierrelouis Docquier, Xavier Banse, Benedicte Brichard, Olivier CornuAbstract:BACKGROUND: Reconstruction of the pelvic arch after resection of a malignant pelvic Tumor remains a major surgical challenge because of the high rate of associated complications. The purpose of this investigation was to assess the functional outcome and complication rate following treatment with a Bone allograft to reconstruct the pelvis. METHODS: Twenty-four consecutive patients underwent excision of a malignant pelvic Bone Tumor and reconstruction with a pelvic Bone allograft. The living patients were followed for a minimum of twenty-four months. There were nineteen primary malignant Bone Tumors, sixteen of which were high-grade sarcomas, and there were five isolated metastases. Patients were examined clinically and radiographically and were assessed functionally with the Musculoskeletal Tumor Society score. RESULTS: The mean age of the patients at the time of the index surgery was thirty-four years, and the mean duration of follow-up was forty-one months. Eighteen of the twenty-four resections involved the periacetabular area and were followed by reconstruction either with a hip prosthesis (thirteen) or with an osteochondral allograft alone (five). The six other resections involved the iliac Bone. All patients received a massive Bone allograft that had been sterilely procured without secondary irradiation. At the time of our last evaluation, eight patients were alive and free of disease. Seven patients had a local recurrence. Neurological deficits were present in six patients, and three had a deep infection. Nonunion of three of the sixteen allografts that could be evaluated was observed. Neither graft fracture nor lysis was observed. Eleven patients underwent surgical revision, with nine of these revisions related to the reconstruction. The average Musculoskeletal Tumor Society score at the time of the latest follow-up was 73% of the maximal possible score. The average score was 82% for the eleven patients with an age of less than twenty years at the time of the index procedure and 65% for the thirteen older patients. Ten patients walked without any assistive device, and five of them had normal function with no or only a slight limp. CONCLUSIONS: Pelvic reconstruction after a limb-sparing resection is associated with a high risk of surgical complications and usually should be reserved for patients with a primary Bone sarcoma. A pelvic allograft can restore the anatomy and provide good functional results, especially in young patients. Nonunion was the most common allograft-related complication.
Olivier Cartiaux - One of the best experts on this subject based on the ideXlab platform.
-
computer assisted planning and patient specific instruments for Bone Tumor resection within the pelvis a series of 11 patients
Sarcoma, 2014Co-Authors: Francois Gouin, Laurent Paul, G Odri, Olivier CartiauxAbstract:Pelvic Bone Tumor resection is challenging due to complex geometry, limited visibility, and restricted workspace. Accurate resection including a safe margin is required to decrease the risk of local recurrence. This clinical study reports 11 cases of pelvic Bone Tumor resected by using patient-specific instruments. Magnetic resonance imaging was used to delineate the Tumor and computerized tomography to localize it in 3D. Resection planning consisted in desired cutting planes around the Tumor including a safe margin. The instruments were designed to fit into unique position on the bony structure and to indicate the desired resection planes. Intraoperatively, instruments were positioned freehand by the surgeon and Bone cutting was performed with an oscillating saw. Histopathological analysis of resected specimens showed Tumor-free Bone resection margins for all cases. Available postoperative computed tomography was registered to preoperative computed tomography to measure location accuracy (minimal distance between an achieved and desired cut planes) and errors on safe margin (minimal distance between the achieved cut planes and the Tumor boundary). The location accuracy averaged 2.5 mm. Errors in safe margin averaged −0.8 mm. Instruments described in this study may improve Bone Tumor surgery within the pelvis by providing good cutting accuracy and clinically acceptable margins.
-
improved accuracy with 3d planning and patient specific instruments during simulated pelvic Bone Tumor surgery
Annals of Biomedical Engineering, 2014Co-Authors: Olivier Cartiaux, Laurent Paul, Pierrelouis Docquier, Xavier Banse, Bernard G FrancqAbstract:In orthopaedic surgery, resection of pelvic Bone Tumors can be inaccurate due to complex geometry, limited visibility and restricted working space of the pelvis. The present study investigated accuracy of patient-specific instrumentation (PSI) for Bone-cutting during simulated Tumor surgery within the pelvis. A synthetic pelvic Bone model was imaged using a CT-scanner. The set of images was reconstructed in 3D and resection of a simulated periacetabular Tumor was defined with four target planes (ischium, pubis, anterior ilium, and posterior ilium) with a 10-mm desired safe margin. Patient-specific instruments for Bone-cutting were designed and manufactured using rapid-prototyping technology. Twenty-four surgeons (10 senior and 14 junior) were asked to perform Tumor resection. After cutting, ISO1101 location and flatness parameters, achieved surgical margins and the time were measured. With PSI, the location accuracy of the cut planes with respect to the target planes averaged 1 and 1.2 mm in the anterior and posterior ilium, 2 mm in the pubis and 3.7 mm in the ischium (p < 0.0001). Results in terms of the location of the cut planes and the achieved surgical margins did not reveal any significant difference between senior and junior surgeons (p = 0.2214 and 0.8449, respectively). The maximum differences between the achieved margins and the 10-mm desired safe margin were found in the pubis (3.1 and 5.1 mm for senior and junior surgeons respectively). Of the 24 simulated resection, there was no intralesional Tumor cutting. This study demonstrates that using PSI technology during simulated Bone cuts of the pelvis can provide good cutting accuracy. Compared to a previous report on computer assistance for pelvic Bone cutting, PSI technology clearly demonstrates an equivalent value-added for Bone cutting accuracy than navigation technology. When in vivo validated, PSI technology may improve pelvic Bone Tumor surgery by providing clinically acceptable margins.
-
computer assisted planning and navigation improves cutting accuracy during simulated Bone Tumor surgery of the pelvis
Computer Aided Surgery, 2013Co-Authors: Olivier Cartiaux, Laurent Paul, Xavier Banse, Bernard G Francq, Carleric Aubin, Pierrelouis DocquierAbstract:Background: Resection of Bone Tumors within the pelvis requires good cutting accuracy to achieve satisfactory safe margins. Manually controlled Bone cutting can result in serious errors, especially due to the complex three-dimensional geometry, limited visibility, and restricted working space of the pelvic Bone. This experimental study investigated cutting accuracy during navigated and non-navigated simulated Bone Tumor cutting in the pelvis. Methods: A periacetabular Tumor resection was simulated using a pelvic Bone model. Twenty-three operators (10 senior and 13 junior surgeons) were asked to perform the Tumor cutting, initially according to a freehand procedure and later with the aid of a navigation system. Before cutting, each operator used preoperative planning software to define four target planes around the Tumor with a 10-mm desired safe margin. After cutting, the location and flatness of the cut planes were measured, as well as the achieved surgical margins and the time required for each cutting procedure. Results: The location of the cut planes with respect to the target planes was significantly improved by using the navigated cutting procedure, averaging 2.8 mm as compared to 11.2 mm for the freehand cutting procedure (p < 0.001). There was no intralesional Tumor cutting when using the navigation system. The maximum difference between the achieved margins and the 10-mm desired safe margin was 6.5 mm with the navigated cutting process (compared to 13 mm with the freehand cutting process). Conclusions: Cutting accuracy during simulated Bone cuts of the pelvis can be significantly improved by using a freehand process assisted by a navigation system. When fully validated with complementary in vivo studies, the planning and navigation-guided technologies that have been developed for the present study may improve Bone cutting accuracy during pelvic Tumor resection by providing clinically acceptable margins.
-
computer assisted planning and patient specific instruments for Bone Tumor surgery within the pelvis an experimental study
13th Annual Meeting of the International Society for Computer Assisted Orthopaedic Surgery, 2013Co-Authors: Laurent Paul, Pierrelouis Docquier, Xavier Banse, Olivier CartiauxAbstract:Resecting Bone Tumors within the pelvis is challenging due to the complex geometry, limited visibility and restricted workspace of the pelvic Bone. Tumor resection requires good cutting accuracy to achieve satisfactory margins and avoid the risk of local recurrence. Computer-assisted technologies have been developed for pelvic Bone Tumor surgeries to improve cutting accuracy. Preoperative planning and intraoperative navigation are available for the positioning of surgical tools (chisels, burrs, saws…) [1]: clinical studies already have demonstrated the feasibility of achieving Tumor-free resection margins within the pelvis with the aid of these assistance technologies. Patient-specific instrumentation technology has been developed as an alternative to intraoperative navigation. Commercially available patient-specific instruments exist for total knee arthroplasty [2], pedicle screw insertion [3] and pelvic osteotomy [4]. To date, no studies have reported accuracy data on achieved margins during pelvic Bone Tumor resections with patient-specific instruments. This experimental study investigated the accuracy of patient-specific instrumentation technology for Bone cutting during simulated Tumor surgeries within the pelvis.
Al J Beitz - One of the best experts on this subject based on the ideXlab platform.
-
the relationship of Bone Tumor induced spinal cord astrocyte activation and aromatase expression to mechanical hyperalgesia and cold hypersensitivity in intact female and ovariectomized mice
Neuroscience, 2016Co-Authors: Branden A Smeester, Elaine E Obrien, K S Michlitsch, Al J BeitzAbstract:Recently, our group established a relationship between Tumor-induced spinal cord astrocyte activation and aromatase expression and the development of Bone Tumor nociception in male mice. As an extension of this work, we now report on the association of Tumor-induced mechanical hyperalgesia and cold hypersensitivity to changes in spinal cord dorsal horn GFAP and aromatase expression in intact (INT) female mice and the effect of ovariectomy on these parameters. Implantation of fibrosarcoma cells produced robust mechanical hyperalgesia in INT animals, while ovariectomized (OVX) females had significantly less mechanical hyperalgesia. Cold hypersensitivity was apparent by post-implantation day 7 in INT and OVX females compared to their saline-injected controls and increased throughout the experiment. The decrease in mechanical hyperalgesia in OVX females was mirrored by significant decreases in spinal astrocyte activity in laminae I-II, III-IV, V-VI and X and aromatase expression in laminae V-VI and X in the dorsal horn of Tumor-bearing animals. Administration of the aromatase inhibitor letrozole reduced Tumor-induced hyperalgesia in INT females only suggesting that the Tumor-induced increase in aromatase expression and its associated increase in spinal estrogen play a role in the development of Bone Tumor-induced hyperalgesia. Finally, intrathecal (i.t.) administration of 17β-estradiol caused a significant increase in Tumor-induced hyperalgesia in INT Tumor-bearing females. Since i.t. 17β-estradiol increases Tumor pain and ovariectomy significantly decreases Tumor pain, as well as spinal aromatase, estrogen may play a critical role in the spinal cord response to the changing Tumor environment and the development of Tumor-induced nociception.
-
colocalization of aromatase in spinal cord astrocytes differences in expression and relationship to mechanical and thermal hyperalgesia in murine models of a painful and a non painful Bone Tumor
Neuroscience, 2015Co-Authors: Elaine E Obrien, Branden A Smeester, K S Michlitsch, Al J BeitzAbstract:Abstract While spinal cord astrocytes play a key role in the generation of cancer pain, there have been no studies that have examined the relationship of Tumor-induced astrocyte activation and aromatase expression during the development of cancer pain. Here, we examined Tumor-induced mechanical hyperalgesia and cold allodynia, and changes in Glial fibrillary acid protein (GFAP) and aromatase expression in murine models of painful and non-painful Bone cancer. We demonstrate that implantation of fibrosarcoma cells, but not melanoma cells, produces robust mechanical hyperalgesia and cold allodynia in Tumor-bearing mice compared to saline-injected controls. Secondly, this increase in mechanical hyperalgesia and cold allodynia is mirrored by significant increases in both spinal astrocyte activity and aromatase expression in the dorsal horn of fibrosarcoma-bearing mice. Importantly, we show that aromatase is only found within a subset of astrocytes and not in neurons in the lumbar spinal cord. Finally, administration of an aromatase inhibitor reduced Tumor-induced hyperalgesia in fibrosarcoma-bearing animals. We conclude that a painful fibrosarcoma Tumor induces a significant increase in spinal astrocyte activation and aromatase expression and that the up-regulation of aromatase plays a role in the development of Bone Tumor-induced hyperalgesia. Since spinal aromatase is also upregulated, but to a lesser extent, in non-painful melanoma Bone Tumors, it may also be neuroprotective and responsive to the changing Tumor environment.
Xavier Banse - One of the best experts on this subject based on the ideXlab platform.
-
improved accuracy with 3d planning and patient specific instruments during simulated pelvic Bone Tumor surgery
Annals of Biomedical Engineering, 2014Co-Authors: Olivier Cartiaux, Laurent Paul, Pierrelouis Docquier, Xavier Banse, Bernard G FrancqAbstract:In orthopaedic surgery, resection of pelvic Bone Tumors can be inaccurate due to complex geometry, limited visibility and restricted working space of the pelvis. The present study investigated accuracy of patient-specific instrumentation (PSI) for Bone-cutting during simulated Tumor surgery within the pelvis. A synthetic pelvic Bone model was imaged using a CT-scanner. The set of images was reconstructed in 3D and resection of a simulated periacetabular Tumor was defined with four target planes (ischium, pubis, anterior ilium, and posterior ilium) with a 10-mm desired safe margin. Patient-specific instruments for Bone-cutting were designed and manufactured using rapid-prototyping technology. Twenty-four surgeons (10 senior and 14 junior) were asked to perform Tumor resection. After cutting, ISO1101 location and flatness parameters, achieved surgical margins and the time were measured. With PSI, the location accuracy of the cut planes with respect to the target planes averaged 1 and 1.2 mm in the anterior and posterior ilium, 2 mm in the pubis and 3.7 mm in the ischium (p < 0.0001). Results in terms of the location of the cut planes and the achieved surgical margins did not reveal any significant difference between senior and junior surgeons (p = 0.2214 and 0.8449, respectively). The maximum differences between the achieved margins and the 10-mm desired safe margin were found in the pubis (3.1 and 5.1 mm for senior and junior surgeons respectively). Of the 24 simulated resection, there was no intralesional Tumor cutting. This study demonstrates that using PSI technology during simulated Bone cuts of the pelvis can provide good cutting accuracy. Compared to a previous report on computer assistance for pelvic Bone cutting, PSI technology clearly demonstrates an equivalent value-added for Bone cutting accuracy than navigation technology. When in vivo validated, PSI technology may improve pelvic Bone Tumor surgery by providing clinically acceptable margins.
-
computer assisted planning and navigation improves cutting accuracy during simulated Bone Tumor surgery of the pelvis
Computer Aided Surgery, 2013Co-Authors: Olivier Cartiaux, Laurent Paul, Xavier Banse, Bernard G Francq, Carleric Aubin, Pierrelouis DocquierAbstract:Background: Resection of Bone Tumors within the pelvis requires good cutting accuracy to achieve satisfactory safe margins. Manually controlled Bone cutting can result in serious errors, especially due to the complex three-dimensional geometry, limited visibility, and restricted working space of the pelvic Bone. This experimental study investigated cutting accuracy during navigated and non-navigated simulated Bone Tumor cutting in the pelvis. Methods: A periacetabular Tumor resection was simulated using a pelvic Bone model. Twenty-three operators (10 senior and 13 junior surgeons) were asked to perform the Tumor cutting, initially according to a freehand procedure and later with the aid of a navigation system. Before cutting, each operator used preoperative planning software to define four target planes around the Tumor with a 10-mm desired safe margin. After cutting, the location and flatness of the cut planes were measured, as well as the achieved surgical margins and the time required for each cutting procedure. Results: The location of the cut planes with respect to the target planes was significantly improved by using the navigated cutting procedure, averaging 2.8 mm as compared to 11.2 mm for the freehand cutting procedure (p < 0.001). There was no intralesional Tumor cutting when using the navigation system. The maximum difference between the achieved margins and the 10-mm desired safe margin was 6.5 mm with the navigated cutting process (compared to 13 mm with the freehand cutting process). Conclusions: Cutting accuracy during simulated Bone cuts of the pelvis can be significantly improved by using a freehand process assisted by a navigation system. When fully validated with complementary in vivo studies, the planning and navigation-guided technologies that have been developed for the present study may improve Bone cutting accuracy during pelvic Tumor resection by providing clinically acceptable margins.
-
computer assisted planning and patient specific instruments for Bone Tumor surgery within the pelvis an experimental study
13th Annual Meeting of the International Society for Computer Assisted Orthopaedic Surgery, 2013Co-Authors: Laurent Paul, Pierrelouis Docquier, Xavier Banse, Olivier CartiauxAbstract:Resecting Bone Tumors within the pelvis is challenging due to the complex geometry, limited visibility and restricted workspace of the pelvic Bone. Tumor resection requires good cutting accuracy to achieve satisfactory margins and avoid the risk of local recurrence. Computer-assisted technologies have been developed for pelvic Bone Tumor surgeries to improve cutting accuracy. Preoperative planning and intraoperative navigation are available for the positioning of surgical tools (chisels, burrs, saws…) [1]: clinical studies already have demonstrated the feasibility of achieving Tumor-free resection margins within the pelvis with the aid of these assistance technologies. Patient-specific instrumentation technology has been developed as an alternative to intraoperative navigation. Commercially available patient-specific instruments exist for total knee arthroplasty [2], pedicle screw insertion [3] and pelvic osteotomy [4]. To date, no studies have reported accuracy data on achieved margins during pelvic Bone Tumor resections with patient-specific instruments. This experimental study investigated the accuracy of patient-specific instrumentation technology for Bone cutting during simulated Tumor surgeries within the pelvis.
-
pelvic reconstruction with a structural pelvic allograft after resection of a malignant Bone Tumor
Journal of Bone and Joint Surgery American Volume, 2007Co-Authors: Christian Delloye, Pierrelouis Docquier, Xavier Banse, Benedicte Brichard, Olivier CornuAbstract:BACKGROUND: Reconstruction of the pelvic arch after resection of a malignant pelvic Tumor remains a major surgical challenge because of the high rate of associated complications. The purpose of this investigation was to assess the functional outcome and complication rate following treatment with a Bone allograft to reconstruct the pelvis. METHODS: Twenty-four consecutive patients underwent excision of a malignant pelvic Bone Tumor and reconstruction with a pelvic Bone allograft. The living patients were followed for a minimum of twenty-four months. There were nineteen primary malignant Bone Tumors, sixteen of which were high-grade sarcomas, and there were five isolated metastases. Patients were examined clinically and radiographically and were assessed functionally with the Musculoskeletal Tumor Society score. RESULTS: The mean age of the patients at the time of the index surgery was thirty-four years, and the mean duration of follow-up was forty-one months. Eighteen of the twenty-four resections involved the periacetabular area and were followed by reconstruction either with a hip prosthesis (thirteen) or with an osteochondral allograft alone (five). The six other resections involved the iliac Bone. All patients received a massive Bone allograft that had been sterilely procured without secondary irradiation. At the time of our last evaluation, eight patients were alive and free of disease. Seven patients had a local recurrence. Neurological deficits were present in six patients, and three had a deep infection. Nonunion of three of the sixteen allografts that could be evaluated was observed. Neither graft fracture nor lysis was observed. Eleven patients underwent surgical revision, with nine of these revisions related to the reconstruction. The average Musculoskeletal Tumor Society score at the time of the latest follow-up was 73% of the maximal possible score. The average score was 82% for the eleven patients with an age of less than twenty years at the time of the index procedure and 65% for the thirteen older patients. Ten patients walked without any assistive device, and five of them had normal function with no or only a slight limp. CONCLUSIONS: Pelvic reconstruction after a limb-sparing resection is associated with a high risk of surgical complications and usually should be reserved for patients with a primary Bone sarcoma. A pelvic allograft can restore the anatomy and provide good functional results, especially in young patients. Nonunion was the most common allograft-related complication.
Michelle Ghert - One of the best experts on this subject based on the ideXlab platform.
-
parathyroid hormone related protein pthrp modulates adhesion migration and invasion in Bone Tumor cells
Bone, 2013Co-Authors: Robert E Turcotte, Michelle GhertAbstract:Parathyroid-hormone-related protein (PTHrP) has been shown to be an important factor in osteolysis in the setting of metastatic carcinoma to the Bone. However, PTHrP may also be central in the setting of primary Bone Tumors. Giant cell Tumor of Bone (GCT) is an aggressive osteolytic Bone Tumor characterized by osteoclast-like giant cells that are recruited by osteoblast-like stromal cells. The stromal cells of GCT are well established as the only neoplastic element of the Tumor, and we have previously shown that PTHrP is highly expressed by these cells both in vitro and in vivo. We have also found that the stromal cells exposed to a monoclonal antibody to PTHrP exhibited rapid plate detachment and quickly died in vitro. Therefore, PTHrP may serve in an autocrine manner to increase cell proliferation and promote invasive properties in GCT. The purpose of this study was to use transcriptomic microarrays and functional assays to examine the effects of PTHrP neutralization on cell adhesion, migration and invasion. Microarray and proteomics data identified genes that were differentially expressed in GCT stromal cells under various PTHrP treatment conditions. Treatment of GCT stromal cells with anti-PTHrP antibodies showed a change in the expression of 13 genes from the integrin family relative to the IgG control. Neutralization of PTHrP reduced cell migration and invasion as evidenced by functional assays. Adhesion and anoikis assays demonstrated that although PTHrP neutralization inhibits cell adhesion properties, cell detachment related to PTHrP neutralization did not result in associated cell death, as expected in mesenchymal stromal cells. Based on the data presented herein, we conclude that PTHrP excreted by GCT stromal cells increases Bone Tumor cell local invasiveness and migration.
-
high infection rate outcomes in long Bone Tumor surgery with endoprosthetic reconstruction in adults a systematic review
Clinical Orthopaedics and Related Research, 2013Co-Authors: Antonella Racano, Theresa J C Pazionis, Forough Farrokhyar, Benjamin Deheshi, Michelle GhertAbstract:Background Limb salvage surgery (LSS) with endoprosthetic replacement is the most common method of reconstruction following Bone Tumor resection in the adult population. The risk of a postoperative infection developing is high when compared with conventional arthroplasty and there are no appropriate guidelines for antibiotic prophylaxis.
-
transcriptomic and proteomic analyses in Bone Tumor cells deciphering parathyroid hormone related protein regulation of the cell cycle and apoptosis
Journal of Bone and Mineral Research, 2012Co-Authors: Robert E Turcotte, Michelle GhertAbstract:Giant cell Tumor of Bone (GCT) is an aggressive skeletal Tumor characterized by local Bone destruction, high recurrence rates, and metastatic potential. Previous works in our laboratory, including functional assays, have shown that neutralization of parathyroid hormone-related protein (PTHrP) in the cell environment inhibits cell proliferation and induces cell death in GCT stromal cells, indicating a role for PTHrP in cell propagation and survival. The objective of this study was to investigate the global gene and protein expression patterns of GCT cells in order to identify the underlying pathways and mechanisms of neoplastic proliferation provided by PTHrP in the Bone microenvironment. Primary stromal cell cultures from 10 patients with GCT were used in this study. Cells were exposed to optimized concentrations of either PTHrP peptide or anti-PTHrP neutralizing antiserum and were analyzed with both cDNA microarray and proteomic microarray assays in triplicate. Hierarchical clustering and principal component analyses confirmed that counteraction of PTHrP in GCT stromal cells results in a clear-cut gene expression pattern distinct from all other treatment groups and the control cell line human fetal osteoblast (hFOB). Multiple bioinformatics tools were used to analyze changes in gene/protein expression and identify important gene ontologies and pathways common to this anti-PTHrP–induced regulatory gene network. PTHrP neutralization interferes with multiple cell survival and apoptosis signaling pathways by triggering both death receptors and cell cycle–mediated apoptosis, particularly via the caspase pathway, TRAIL pathway, JAK-STAT signaling pathway, and cyclin E/CDK2-associated G1/S cell cycle progression. These findings indicate that PTHrP neutralization exhibits anticancer potential by regulating cell-cycle progression and apoptosis in Bone Tumor cells, with the corollary being that PTHrP is a pro-neoplastic factor that can be targeted in the treatment of Bone Tumors. © 2012 American Society for Bone and Mineral Research.