Daniel Shedid - Academia.edu (original) (raw)
Papers by Daniel Shedid
Canadian Journal of Surgery
Radiographic reporting in adolescent idiopathic scoliosis: Is there a discrepancy comparing radio... more Radiographic reporting in adolescent idiopathic scoliosis: Is there a discrepancy comparing radiologists' reports and surgeons' assessments? Karamjot Sidhu, Marina Filezio,
International Journal of Computer Assisted Radiology and Surgery, Jan 4, 2023
Neurosurgery Quarterly, Dec 1, 2004
Spinal tumors are classified by anatomic location as epidural (between the meninges and the bones... more Spinal tumors are classified by anatomic location as epidural (between the meninges and the bones of the spine) intradural extramedullary (within the meninges covering the spinal cord), and intradural intramedullary (inside the spinal cord). The symptoms vary depending on the location and the type of the tumor. These symptoms are caused by compression of the spinal cord or nerve roots, invasion of normal cells by the tumor, ischemia that results from blockage of blood vessels, or hemorrhage. In this article, the different types of spinal cord tumors and their symptomatology are discussed.
Neurosurgery, 2007
CLINICAL PROBLEMS ARE often complex. Problems of great complexity are usually associated with a c... more CLINICAL PROBLEMS ARE often complex. Problems of great complexity are usually associated with a commensurately greater degree of difficulty with respect to the decision making process. This is most certainly true regarding the management of cervical spondylosis. Usually, clinicians make clinically appropriate decisions. However, more often than realized, suboptimal decisions may be made. Therefore, an assessment of the types of errors regarding clinical decision making are worthy of consideration. In this article, a scheme for decision making regarding the management of cervical spondylosis is presented.
Nature clinical practice neurology, Nov 1, 2005
Spinal fusion is the conventional surgical option for treating degenerative disc disease, but it ... more Spinal fusion is the conventional surgical option for treating degenerative disc disease, but it can decrease the spine's overall range of motion, thereby increasing stress on adjacent discs and accelerating their degeneration. Artificial disc replacement should allow motion to be retained at the operative level, and the results of initial trials have been encouraging, but randomized studies are still needed to assess the long-term outcome of this procedure.
Journal of Vascular Surgery, Mar 1, 2002
Background: The increased synthesis of matrix metalloproteinases (MMPs) by aortic smooth muscle c... more Background: The increased synthesis of matrix metalloproteinases (MMPs) by aortic smooth muscle cells (SMCs) is thought to be involved in the etiopathogenesis of abdominal aortic aneurysms (AAAs), but the functional regulation and the activation states of these MMPs remain unclear. In this study, we assessed the expression levels and the functional regulation of several MMPs in the pathogenesis of AAAs. Methods: Human healthy aorta and AAA specimens were homogenized, and the proteolytic activities of MMP-2 and MMP-9 and of the macrophage metalloelastase (MMP-12) were assessed with zymography. Protein expression of MMP-1, MMP-12, membrane-type 1 MMP (MT1-MMP), tissue inhibitor of MMP 1 (TIMP-1), TIMP-2, TIMP-3, α-actin, and β-actin was analyzed with electrophoresis on sodium dodecyl sulfate gels and immunoblotting. Results: MMP-1, MMP-9, and MMP-12 zymogen levels and proteolytic activities were increased in AAAs when compared with healthy aorta. A severe reduction in α-actin-positive vascular SMCs was observed in all the AAA specimens and was correlated with an increase in TIMP-3 but not TIMP-1 or TIMP-2 potential activities. Although pro-MMP-2 activity was decreased, the extent of activated MMP-2 remained unaffected in the AAAs. In accordance with this result, a highly activated MT1-MMP form was also observed in AAAs. Conclusion: These data suggest that chronic aortic wall inflammation is mediated by macrophage infiltration, which may account for the destruction of medial elastin, as reflected by SMC down regulation, through increased levels of active MMP-1 and MMP-12. Moreover, altered MT1-MMP proteolytic turnover and differential regulation of TIMP expression in AAAs suggest that tight regulatory mechanisms are involved in the molecular regulation of MMP activation processes in the pathogenesis of AAAs.
Neurosurgery, 2007
CERVICAL SPONDYLOSIS IS the most common progressive disorder in the aging cervical spine. It resu... more CERVICAL SPONDYLOSIS IS the most common progressive disorder in the aging cervical spine. It results from the process of degeneration of the intervertebral discs and facet joints of the cervical spine. Biomechanically, the disc and the facets are the connecting structures between the vertebrae for the transmission of external forces. They also facilitate cervical spine mobility. Symptoms related to myelopathy and radiculopathy are caused by the formation of osteophytes, which compromise the diameter of the spinal canal. This compromise may also be partially developmental. The developmental process, together with the degenerative process, may cause mechanical pressure on the spinal cord at one or multiple levels. This pressure may produce direct neurological damage or ischemic changes and, thus, lead to spinal cord disturbances. A thorough understanding of the biomechanics, the pathology, the clinical presentation, the radiological evaluation, as well as the surgical indications of cervical spondylosis, is essential for the management of patients with cervical spondylosis.
Humana Press eBooks, Aug 15, 2008
ABSTRACT Spinal tumors may cause a variety of symptoms depending on their type, location, and rat... more ABSTRACT Spinal tumors may cause a variety of symptoms depending on their type, location, and rate of growth. The symptomatology differs depending on tumor location (e.g., extradural or vertebral column vs intradural-extramedullary vs intramedullary). Vertebral column tumors are divided into primary and metastatic. Primary tumors include neoplasms of the marrow (e.g., multiple myeloma), and tumors of the bone or the cartilage of the spine (1). Metastatic spinal pathology is much more common than primary neoplastic pathology. The spine is the most common site of skeletal metastasis (2). A spinal metastasis is found in as many as 70 to 90% of patients dying of cancer (3,4). The most common tumors that metastasize to the spine are tumors of the lung, breast, prostate, kidney, lymphoma, melanoma, and gastrointestinal tract (5). In the pediatric population, spinal metastasis commonly arise from neuroblastoma, rhabdomyosarcoma, leukemia, and histiocytosis; less commonly from lymphoma, Wilms’ tumor, and primitive neuroectodermal tumor (6). Meningiomas and nerve sheath tumors (schwannomas and neurofibromas) comprise the overwhelming majority of the intradural-extramedullary tumors. Astrocytoma, ependymoma, and hemangioblastoma account for the majority of the intramedullary tumors.
Humana Press eBooks, Aug 15, 2008
Spine tumors can be classified by their relation to the spinal canal and its coverings. Tumors ca... more Spine tumors can be classified by their relation to the spinal canal and its coverings. Tumors can arise from the different tissue types around the spinal column, such as neural tissue, meningeal tissue, bone, and cartilage. Furthermore, distant primary tumors can metastasize to the spine by hematogenous or lymphatic routes. Both benign and malignant tumors may occur in either location and at any level of the spine.
INTRODUCTION The development of cervical deformity, such as kyphosis, may be secondary to advance... more INTRODUCTION The development of cervical deformity, such as kyphosis, may be secondary to advanced degenerative disease, trauma, neoplastic disease, or postsurgical changes. Cervical kyphosis may develop after either ventral or dorsal approaches. After ventral cervical surgery, kyphosis may result from pseudarthrosis or the failure to restore adequate lordosis. Following dorsal surgery, kyphosis may develop and progress in response to disruption of the natural stabilizing structures, such as the tension band of the dorsal cervical spine. ABSTRACT This article addresses basic concepts in the biomechanics of cervical deformity correction. We highlight the principles of deformity correction, followed by a discussion of surgical strategies, including ventral, dorsal and combined approaches. We emphasize the ventral approach to the correction of postsurgical cervical kyphosis.
Journal of Spinal Disorders & Techniques, Apr 1, 2014
Study Design: Case report of 3 patients with high-grade isthmic spondylolisthesis treated using a... more Study Design: Case report of 3 patients with high-grade isthmic spondylolisthesis treated using a novel minimally invasive technique using a posterior transsacral rod. Objective: To assess the efficacy, safety, and advantages of this approach in the treatment of high-grade L5-S1 spondylolisthesis. Summary of Background Data: Surgical treatment of high-grade isthmic spondylolisthesis at the L5-S1 level is technically demanding. The most commonly used procedure is posterior spinal fusion. In this report, we present a new minimally invasive technique for the treatment high-grade isthmic spondylolisthesis in 3 patients with sagittally balanced spines. Materials and Methods: Three patients with high-grade L5-S1 spondylolisthesis underwent L4-S1 fusion with percutaneous pedicle screw fixation supplemented with a transsacral rod implanted through a tubular retractor. We report technical details, clinical, and radiologic results at follow-up. Results: All 3 patients suffered from grade 3 or 4 L5-S1 spondylolisthesis. All patients had neutral sagittal balance on preoperative imaging. There were no postoperative complications and all 3 patients were discharged within 48 hours. At final follow-up (range, 13-18 mo), all patients were pain free off all narcotic pain medication and fusion was observed in all 3 patients. Conclusions: We have shown the technical feasibility of anterior and posterior fusion for severe L5-S1 spondylolisthesis using a minimally invasive percutaneous technique through a transsacral approach. The main advantage of a posterior transsacral axial rod fixation is that it creates a structurally sound anterior column support, thus eliminating the problems related to bone grafts and eliminating the complications associated with an anterior approach. Our preliminary results suggest that this technique is feasible and seems to be associated with favorable outcome, although larger studies are warranted to verify these findings.
Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques
This version may be subject to change during the production process.
Child's Nervous System
Purpose Vertebral hemangiomas are benign, highly vascular spinal lesions that are extremely rare ... more Purpose Vertebral hemangiomas are benign, highly vascular spinal lesions that are extremely rare in the pediatric population. We report a pediatric case of symptomatic vertebral hemangioma treated with total en bloc spondylectomy. Our objective is to demonstrate that en bloc spondylectomy is feasible and addresses some pitfalls of traditional total tumor resection. Methods Our patient presented with bilateral lower limb and perineal paresthesia, paraparesis, as well as urinary retention. Locally aggressive vertebral hemangioma was the presumed diagnosis following imaging. The patient received partial angioembolization to reduce the vascularization of the lesion then underwent total en bloc spondylectomy of T8 under intraoperative neuromonitoring. The intervention was well tolerated. Results Postoperative course was marked by clinical improvement and only transient, treatable complications. On 1-year followup, the patient is neurologically intact, and imaging reveals adequate position of hardware, good alignment, and no tumor recurrence. Conclusion Total en bloc spondylectomy is a feasible procedure in pediatric patients. It reduces local recurrence through reduction of tumor cell contamination and residual tumor and thus may avoid postoperative radiotherapy in select cases. It may also enhance functional neurological recovery by allowing circumferential decompression and increased spinal cord blood flow.
World Neurosurgery, 2021
OBJECTIVE Spinal metastases occur primarily in the thoracic spine (50-60%), less commonly in the ... more OBJECTIVE Spinal metastases occur primarily in the thoracic spine (50-60%), less commonly in the lumbar (30-35%) and, infrequently, cervical spine (10-15%). There has been only one study with limited population comparing the post-operative outcome among cervical, thoracic and lumbar spine metastasis. The aim of this study is to identify whether region of surgically treated spinal metastasis affects post-operative outcomes. METHODS AND MATERIALS A retrospective study of patients who suffered from spinal metastasis was performed. The collected data were the following: age, gender, smoking history, tumor histology, revised Tokuhashi score, pre-operative and post-operative ASIA score, region of spinal metastasis, ambulatory status, surgical approach, surgery time, blood loss, complications, length of hospital stay, post-operative pain relief, post-operative adjuvant therapy, and survival time. Data was analyzed to identify the factors affecting the survival time and post-operative functional outcome. RESULTS We studied 191 spinal metastasis patients including 47 cervical spine metastases, 96 thoracic spine metastases and 48 lumbar spine metastases, with a mean age of 60.91 ± 9.72 years. The overall median survival time was 7 months (95% CI: 2.9-20.63 months). Univariate analysis showed region of the spine involved with metastasis did not significantly affect the survival time and post-operative motor function improvement. Multivariate analysis revealed revised Tokuhashi score, post-operative radiotherapy, and post-operative chemotherapy were independent factors affecting survival time. The rate of 30-day complication among different regions of spine metastasis patients did not reach significance. CONCLUSION The post-operative outcomes of patients undergoing surgery for metastases are not affected by the region of the spine.
Global Spine Journal, 2020
Study Design: Retrospective case series. Objective: Posterior surgery for thoracic disc herniatio... more Study Design: Retrospective case series. Objective: Posterior surgery for thoracic disc herniation was associated with increased morbidity and mortality and new minimally invasive approaches have been recommended for soft disc herniation but not for calcified central disc. The objective of this study is to describe a posterolateral microscopic transpedicular approach for central thoracic disc herniation. Methods: This is a single center retrospective review of all the cases of giant thoracic calcified disc herniation as defined by Hott et al. Presence of myelopathy, percentage of canal compromise, T2 hypersignal, ASIA score, and ambulatory status were recorded. This posterolateral technique using a tubular retractor was thoroughly described. Results: Eight patients were operated upon with a mean follow-up of 16 months. Mean canal compromise was 61%. Mean operative time was 228 minutes and mean operative bleeding was 250 mL. There were no cases of dural tear or neurologic degradation...
Operative Neurosurgery, 2020
BACKGROUND Osteoblastomas are locally aggressive bone tumors typically affecting the posterior el... more BACKGROUND Osteoblastomas are locally aggressive bone tumors typically affecting the posterior elements of the vertebral column. The treatment of choice is total surgical resection, traditionally through an open laminectomy, often with facetectomy and fusion when the lesion is in the foramen. OBJECTIVE To seek an alternative to open surgery, allowing quick and full functional recovery, to meet the youth and athlete population's specific surgical goals. In this population especially, open surgery can be associated with significant impairment and morbidity. METHODS We report a pediatric case of posterior L5 osteoblastoma completely removed using a facet-sparing and fusion-avoiding contralateral foraminal minimally invasive approach using a tubular retractor system. A 12-yr-old male competitive tennis player presented with progressive right L5 lumbosciatica. Computed tomography scan and magnetic resonance imaging revealed a lesion of the right L5 pedicle, facet, and vertebral body...
International Journal of Radiation Oncology*Biology*Physics, 2018
carina and central structures, who were deemed candidates for EBB by a multidisciplinary team of ... more carina and central structures, who were deemed candidates for EBB by a multidisciplinary team of interventional pulmonologists (IP) and radiation oncologists (RO). All patients were treated under general anesthesia and monitored by anesthesia throughout the procedure. Bronchoscopy and localization of target lesions was performed by IP. HDR catheters carrying a marker wire were advanced past obstructive lesion, and in some cases, multiple catheters were used to treat multiple lesions simultaneously. CT simulation was performed to confirm catheter placement, and the target region on CT images corresponding to the obstructive lesion were identified by treating RO. All patients underwent CT-based 3D treatment planning. A dose of 6-7 Gy/fraction was prescribed at 1 cm from catheter surface. Results: Between 2014 and 2017, 24 patients (ages 29-71, mean 52 years) were treated with EPP at our center. Of those, 5 had previously received external beam radiation (EBRT) and 3 had concurrent EBRT and EPP. Overall, a total of 76 EBB treatments were performed, with a median of 3 weekly fractions per patient (range 1-6 fractions) to total dose of 18Gy. Median CTV volume and length treated were 17.6 cm 3 and 47mm, respectively. There were no incidences of major bleeding (>50 mL) or fatal hemoptysis in the 30 days following EPP. Moreover, there were no cases of severe (Grade 3 or higher) CTCAE toxicity reported. After a median follow up of 30 months (range 4-42 months) only 1 out of 16 patients treated with EPP alone required additional EBRT for airway obstruction, 12 months following EPP. Conclusion: Our data suggest the safety and efficacy of an expert multidisciplinary approach to palliating pulmonary airway obstruction using EPP. Appropriate patient selection, the use bronchoscopy for primary target localization and CT based 3D treatment planning combined with a lower dose per fraction provide accurate target coverage while minimizing toxicity. This approach provides effective palliation of airway obstruction and decreased the need for additional EBRT in majority of treated patients. Prospective evaluation of this approach is warranted to better establish the role of EPP in this patient subgroup.
Revue de Chirurgie Orthopédique et Traumatologique, 2016
L'épanchement de Morel-Lavallée est une lésion traumatique rare où des forces de cisaillement pro... more L'épanchement de Morel-Lavallée est une lésion traumatique rare où des forces de cisaillement provoquent un décollement entre les tissus sous-cutanés et le fascia sous-jacent. Cette lésion a été rarement rapportée, expliquant que le diagnostic est souvent méconnu. Alors que le traitement peut être conservateur ou minimalement invasif à un stade précoce, une prise en charge invasive est requise en cas de retard diagnostique. Par ailleurs, les lésions non traitées peuvent entraîner des douleurs, des surinfections ou des tuméfactions sous-cutanées évolutives pouvant être confondues avec des tumeurs des parties molles. Nous rapportons les données cliniques et radiologiques d'un patient de 45 ans présentant un volumineux épanchement de Morel-Lavallée lombaire diagnostiqué tardivement. Nous avons également réalisé une revue de la littérature pour résumer les principaux critères diagnostiques et les modalités de prise en charge.
Morphologie, 2015
Introduction L’evolution technologique en neurochirurgie a permis le developpement de systeme de ... more Introduction L’evolution technologique en neurochirurgie a permis le developpement de systeme de magnification de plus en plus performant. C’est le cas des microscopes operatoires et de l’endoscopie. L’endoscopie 3D VisionSense ® est actuellement disponible. Nous avons souhaite montrer l’utilisation de cette nouvelle technologie dans le cas du traitement des fistules arterio-veineuses (FAV). Materiel et methode Nous presentons 3 cas de FAV, 2 cas de FAV medullaire thoracique et un cas de FAV de fosse posterieure. Dans les trois cas le traitement a ete chirurgical, exclusivement sous endoscopie 3D. L’analyse peroperatoire de l’anatomie est presentee sous forme de video. Resultats Une fois exposee, dans chaque cas la fistule a pu etre aisement exclue sous magnification avec l’endoscope 3D. L’intervention s’est deroulee sans incident et les suites operatoires ont ete marquees par une amelioration clinique. Les angiographies ont confirme l’exclusion de la fistule durale. Conclusion L’endoscopie 3D permet une magnification importante tout en preservant la profondeur de champ pour une excellente visualisation et appreciation des rapports vasculaires et nerveux. Dans le cas d’une fistule durale l’exploration est facilitee en raison de la maniabilite de l’optique, contrairement au microscope.
Canadian Journal of Surgery
Radiographic reporting in adolescent idiopathic scoliosis: Is there a discrepancy comparing radio... more Radiographic reporting in adolescent idiopathic scoliosis: Is there a discrepancy comparing radiologists' reports and surgeons' assessments? Karamjot Sidhu, Marina Filezio,
International Journal of Computer Assisted Radiology and Surgery, Jan 4, 2023
Neurosurgery Quarterly, Dec 1, 2004
Spinal tumors are classified by anatomic location as epidural (between the meninges and the bones... more Spinal tumors are classified by anatomic location as epidural (between the meninges and the bones of the spine) intradural extramedullary (within the meninges covering the spinal cord), and intradural intramedullary (inside the spinal cord). The symptoms vary depending on the location and the type of the tumor. These symptoms are caused by compression of the spinal cord or nerve roots, invasion of normal cells by the tumor, ischemia that results from blockage of blood vessels, or hemorrhage. In this article, the different types of spinal cord tumors and their symptomatology are discussed.
Neurosurgery, 2007
CLINICAL PROBLEMS ARE often complex. Problems of great complexity are usually associated with a c... more CLINICAL PROBLEMS ARE often complex. Problems of great complexity are usually associated with a commensurately greater degree of difficulty with respect to the decision making process. This is most certainly true regarding the management of cervical spondylosis. Usually, clinicians make clinically appropriate decisions. However, more often than realized, suboptimal decisions may be made. Therefore, an assessment of the types of errors regarding clinical decision making are worthy of consideration. In this article, a scheme for decision making regarding the management of cervical spondylosis is presented.
Nature clinical practice neurology, Nov 1, 2005
Spinal fusion is the conventional surgical option for treating degenerative disc disease, but it ... more Spinal fusion is the conventional surgical option for treating degenerative disc disease, but it can decrease the spine's overall range of motion, thereby increasing stress on adjacent discs and accelerating their degeneration. Artificial disc replacement should allow motion to be retained at the operative level, and the results of initial trials have been encouraging, but randomized studies are still needed to assess the long-term outcome of this procedure.
Journal of Vascular Surgery, Mar 1, 2002
Background: The increased synthesis of matrix metalloproteinases (MMPs) by aortic smooth muscle c... more Background: The increased synthesis of matrix metalloproteinases (MMPs) by aortic smooth muscle cells (SMCs) is thought to be involved in the etiopathogenesis of abdominal aortic aneurysms (AAAs), but the functional regulation and the activation states of these MMPs remain unclear. In this study, we assessed the expression levels and the functional regulation of several MMPs in the pathogenesis of AAAs. Methods: Human healthy aorta and AAA specimens were homogenized, and the proteolytic activities of MMP-2 and MMP-9 and of the macrophage metalloelastase (MMP-12) were assessed with zymography. Protein expression of MMP-1, MMP-12, membrane-type 1 MMP (MT1-MMP), tissue inhibitor of MMP 1 (TIMP-1), TIMP-2, TIMP-3, α-actin, and β-actin was analyzed with electrophoresis on sodium dodecyl sulfate gels and immunoblotting. Results: MMP-1, MMP-9, and MMP-12 zymogen levels and proteolytic activities were increased in AAAs when compared with healthy aorta. A severe reduction in α-actin-positive vascular SMCs was observed in all the AAA specimens and was correlated with an increase in TIMP-3 but not TIMP-1 or TIMP-2 potential activities. Although pro-MMP-2 activity was decreased, the extent of activated MMP-2 remained unaffected in the AAAs. In accordance with this result, a highly activated MT1-MMP form was also observed in AAAs. Conclusion: These data suggest that chronic aortic wall inflammation is mediated by macrophage infiltration, which may account for the destruction of medial elastin, as reflected by SMC down regulation, through increased levels of active MMP-1 and MMP-12. Moreover, altered MT1-MMP proteolytic turnover and differential regulation of TIMP expression in AAAs suggest that tight regulatory mechanisms are involved in the molecular regulation of MMP activation processes in the pathogenesis of AAAs.
Neurosurgery, 2007
CERVICAL SPONDYLOSIS IS the most common progressive disorder in the aging cervical spine. It resu... more CERVICAL SPONDYLOSIS IS the most common progressive disorder in the aging cervical spine. It results from the process of degeneration of the intervertebral discs and facet joints of the cervical spine. Biomechanically, the disc and the facets are the connecting structures between the vertebrae for the transmission of external forces. They also facilitate cervical spine mobility. Symptoms related to myelopathy and radiculopathy are caused by the formation of osteophytes, which compromise the diameter of the spinal canal. This compromise may also be partially developmental. The developmental process, together with the degenerative process, may cause mechanical pressure on the spinal cord at one or multiple levels. This pressure may produce direct neurological damage or ischemic changes and, thus, lead to spinal cord disturbances. A thorough understanding of the biomechanics, the pathology, the clinical presentation, the radiological evaluation, as well as the surgical indications of cervical spondylosis, is essential for the management of patients with cervical spondylosis.
Humana Press eBooks, Aug 15, 2008
ABSTRACT Spinal tumors may cause a variety of symptoms depending on their type, location, and rat... more ABSTRACT Spinal tumors may cause a variety of symptoms depending on their type, location, and rate of growth. The symptomatology differs depending on tumor location (e.g., extradural or vertebral column vs intradural-extramedullary vs intramedullary). Vertebral column tumors are divided into primary and metastatic. Primary tumors include neoplasms of the marrow (e.g., multiple myeloma), and tumors of the bone or the cartilage of the spine (1). Metastatic spinal pathology is much more common than primary neoplastic pathology. The spine is the most common site of skeletal metastasis (2). A spinal metastasis is found in as many as 70 to 90% of patients dying of cancer (3,4). The most common tumors that metastasize to the spine are tumors of the lung, breast, prostate, kidney, lymphoma, melanoma, and gastrointestinal tract (5). In the pediatric population, spinal metastasis commonly arise from neuroblastoma, rhabdomyosarcoma, leukemia, and histiocytosis; less commonly from lymphoma, Wilms’ tumor, and primitive neuroectodermal tumor (6). Meningiomas and nerve sheath tumors (schwannomas and neurofibromas) comprise the overwhelming majority of the intradural-extramedullary tumors. Astrocytoma, ependymoma, and hemangioblastoma account for the majority of the intramedullary tumors.
Humana Press eBooks, Aug 15, 2008
Spine tumors can be classified by their relation to the spinal canal and its coverings. Tumors ca... more Spine tumors can be classified by their relation to the spinal canal and its coverings. Tumors can arise from the different tissue types around the spinal column, such as neural tissue, meningeal tissue, bone, and cartilage. Furthermore, distant primary tumors can metastasize to the spine by hematogenous or lymphatic routes. Both benign and malignant tumors may occur in either location and at any level of the spine.
INTRODUCTION The development of cervical deformity, such as kyphosis, may be secondary to advance... more INTRODUCTION The development of cervical deformity, such as kyphosis, may be secondary to advanced degenerative disease, trauma, neoplastic disease, or postsurgical changes. Cervical kyphosis may develop after either ventral or dorsal approaches. After ventral cervical surgery, kyphosis may result from pseudarthrosis or the failure to restore adequate lordosis. Following dorsal surgery, kyphosis may develop and progress in response to disruption of the natural stabilizing structures, such as the tension band of the dorsal cervical spine. ABSTRACT This article addresses basic concepts in the biomechanics of cervical deformity correction. We highlight the principles of deformity correction, followed by a discussion of surgical strategies, including ventral, dorsal and combined approaches. We emphasize the ventral approach to the correction of postsurgical cervical kyphosis.
Journal of Spinal Disorders & Techniques, Apr 1, 2014
Study Design: Case report of 3 patients with high-grade isthmic spondylolisthesis treated using a... more Study Design: Case report of 3 patients with high-grade isthmic spondylolisthesis treated using a novel minimally invasive technique using a posterior transsacral rod. Objective: To assess the efficacy, safety, and advantages of this approach in the treatment of high-grade L5-S1 spondylolisthesis. Summary of Background Data: Surgical treatment of high-grade isthmic spondylolisthesis at the L5-S1 level is technically demanding. The most commonly used procedure is posterior spinal fusion. In this report, we present a new minimally invasive technique for the treatment high-grade isthmic spondylolisthesis in 3 patients with sagittally balanced spines. Materials and Methods: Three patients with high-grade L5-S1 spondylolisthesis underwent L4-S1 fusion with percutaneous pedicle screw fixation supplemented with a transsacral rod implanted through a tubular retractor. We report technical details, clinical, and radiologic results at follow-up. Results: All 3 patients suffered from grade 3 or 4 L5-S1 spondylolisthesis. All patients had neutral sagittal balance on preoperative imaging. There were no postoperative complications and all 3 patients were discharged within 48 hours. At final follow-up (range, 13-18 mo), all patients were pain free off all narcotic pain medication and fusion was observed in all 3 patients. Conclusions: We have shown the technical feasibility of anterior and posterior fusion for severe L5-S1 spondylolisthesis using a minimally invasive percutaneous technique through a transsacral approach. The main advantage of a posterior transsacral axial rod fixation is that it creates a structurally sound anterior column support, thus eliminating the problems related to bone grafts and eliminating the complications associated with an anterior approach. Our preliminary results suggest that this technique is feasible and seems to be associated with favorable outcome, although larger studies are warranted to verify these findings.
Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques
This version may be subject to change during the production process.
Child's Nervous System
Purpose Vertebral hemangiomas are benign, highly vascular spinal lesions that are extremely rare ... more Purpose Vertebral hemangiomas are benign, highly vascular spinal lesions that are extremely rare in the pediatric population. We report a pediatric case of symptomatic vertebral hemangioma treated with total en bloc spondylectomy. Our objective is to demonstrate that en bloc spondylectomy is feasible and addresses some pitfalls of traditional total tumor resection. Methods Our patient presented with bilateral lower limb and perineal paresthesia, paraparesis, as well as urinary retention. Locally aggressive vertebral hemangioma was the presumed diagnosis following imaging. The patient received partial angioembolization to reduce the vascularization of the lesion then underwent total en bloc spondylectomy of T8 under intraoperative neuromonitoring. The intervention was well tolerated. Results Postoperative course was marked by clinical improvement and only transient, treatable complications. On 1-year followup, the patient is neurologically intact, and imaging reveals adequate position of hardware, good alignment, and no tumor recurrence. Conclusion Total en bloc spondylectomy is a feasible procedure in pediatric patients. It reduces local recurrence through reduction of tumor cell contamination and residual tumor and thus may avoid postoperative radiotherapy in select cases. It may also enhance functional neurological recovery by allowing circumferential decompression and increased spinal cord blood flow.
World Neurosurgery, 2021
OBJECTIVE Spinal metastases occur primarily in the thoracic spine (50-60%), less commonly in the ... more OBJECTIVE Spinal metastases occur primarily in the thoracic spine (50-60%), less commonly in the lumbar (30-35%) and, infrequently, cervical spine (10-15%). There has been only one study with limited population comparing the post-operative outcome among cervical, thoracic and lumbar spine metastasis. The aim of this study is to identify whether region of surgically treated spinal metastasis affects post-operative outcomes. METHODS AND MATERIALS A retrospective study of patients who suffered from spinal metastasis was performed. The collected data were the following: age, gender, smoking history, tumor histology, revised Tokuhashi score, pre-operative and post-operative ASIA score, region of spinal metastasis, ambulatory status, surgical approach, surgery time, blood loss, complications, length of hospital stay, post-operative pain relief, post-operative adjuvant therapy, and survival time. Data was analyzed to identify the factors affecting the survival time and post-operative functional outcome. RESULTS We studied 191 spinal metastasis patients including 47 cervical spine metastases, 96 thoracic spine metastases and 48 lumbar spine metastases, with a mean age of 60.91 ± 9.72 years. The overall median survival time was 7 months (95% CI: 2.9-20.63 months). Univariate analysis showed region of the spine involved with metastasis did not significantly affect the survival time and post-operative motor function improvement. Multivariate analysis revealed revised Tokuhashi score, post-operative radiotherapy, and post-operative chemotherapy were independent factors affecting survival time. The rate of 30-day complication among different regions of spine metastasis patients did not reach significance. CONCLUSION The post-operative outcomes of patients undergoing surgery for metastases are not affected by the region of the spine.
Global Spine Journal, 2020
Study Design: Retrospective case series. Objective: Posterior surgery for thoracic disc herniatio... more Study Design: Retrospective case series. Objective: Posterior surgery for thoracic disc herniation was associated with increased morbidity and mortality and new minimally invasive approaches have been recommended for soft disc herniation but not for calcified central disc. The objective of this study is to describe a posterolateral microscopic transpedicular approach for central thoracic disc herniation. Methods: This is a single center retrospective review of all the cases of giant thoracic calcified disc herniation as defined by Hott et al. Presence of myelopathy, percentage of canal compromise, T2 hypersignal, ASIA score, and ambulatory status were recorded. This posterolateral technique using a tubular retractor was thoroughly described. Results: Eight patients were operated upon with a mean follow-up of 16 months. Mean canal compromise was 61%. Mean operative time was 228 minutes and mean operative bleeding was 250 mL. There were no cases of dural tear or neurologic degradation...
Operative Neurosurgery, 2020
BACKGROUND Osteoblastomas are locally aggressive bone tumors typically affecting the posterior el... more BACKGROUND Osteoblastomas are locally aggressive bone tumors typically affecting the posterior elements of the vertebral column. The treatment of choice is total surgical resection, traditionally through an open laminectomy, often with facetectomy and fusion when the lesion is in the foramen. OBJECTIVE To seek an alternative to open surgery, allowing quick and full functional recovery, to meet the youth and athlete population's specific surgical goals. In this population especially, open surgery can be associated with significant impairment and morbidity. METHODS We report a pediatric case of posterior L5 osteoblastoma completely removed using a facet-sparing and fusion-avoiding contralateral foraminal minimally invasive approach using a tubular retractor system. A 12-yr-old male competitive tennis player presented with progressive right L5 lumbosciatica. Computed tomography scan and magnetic resonance imaging revealed a lesion of the right L5 pedicle, facet, and vertebral body...
International Journal of Radiation Oncology*Biology*Physics, 2018
carina and central structures, who were deemed candidates for EBB by a multidisciplinary team of ... more carina and central structures, who were deemed candidates for EBB by a multidisciplinary team of interventional pulmonologists (IP) and radiation oncologists (RO). All patients were treated under general anesthesia and monitored by anesthesia throughout the procedure. Bronchoscopy and localization of target lesions was performed by IP. HDR catheters carrying a marker wire were advanced past obstructive lesion, and in some cases, multiple catheters were used to treat multiple lesions simultaneously. CT simulation was performed to confirm catheter placement, and the target region on CT images corresponding to the obstructive lesion were identified by treating RO. All patients underwent CT-based 3D treatment planning. A dose of 6-7 Gy/fraction was prescribed at 1 cm from catheter surface. Results: Between 2014 and 2017, 24 patients (ages 29-71, mean 52 years) were treated with EPP at our center. Of those, 5 had previously received external beam radiation (EBRT) and 3 had concurrent EBRT and EPP. Overall, a total of 76 EBB treatments were performed, with a median of 3 weekly fractions per patient (range 1-6 fractions) to total dose of 18Gy. Median CTV volume and length treated were 17.6 cm 3 and 47mm, respectively. There were no incidences of major bleeding (>50 mL) or fatal hemoptysis in the 30 days following EPP. Moreover, there were no cases of severe (Grade 3 or higher) CTCAE toxicity reported. After a median follow up of 30 months (range 4-42 months) only 1 out of 16 patients treated with EPP alone required additional EBRT for airway obstruction, 12 months following EPP. Conclusion: Our data suggest the safety and efficacy of an expert multidisciplinary approach to palliating pulmonary airway obstruction using EPP. Appropriate patient selection, the use bronchoscopy for primary target localization and CT based 3D treatment planning combined with a lower dose per fraction provide accurate target coverage while minimizing toxicity. This approach provides effective palliation of airway obstruction and decreased the need for additional EBRT in majority of treated patients. Prospective evaluation of this approach is warranted to better establish the role of EPP in this patient subgroup.
Revue de Chirurgie Orthopédique et Traumatologique, 2016
L'épanchement de Morel-Lavallée est une lésion traumatique rare où des forces de cisaillement pro... more L'épanchement de Morel-Lavallée est une lésion traumatique rare où des forces de cisaillement provoquent un décollement entre les tissus sous-cutanés et le fascia sous-jacent. Cette lésion a été rarement rapportée, expliquant que le diagnostic est souvent méconnu. Alors que le traitement peut être conservateur ou minimalement invasif à un stade précoce, une prise en charge invasive est requise en cas de retard diagnostique. Par ailleurs, les lésions non traitées peuvent entraîner des douleurs, des surinfections ou des tuméfactions sous-cutanées évolutives pouvant être confondues avec des tumeurs des parties molles. Nous rapportons les données cliniques et radiologiques d'un patient de 45 ans présentant un volumineux épanchement de Morel-Lavallée lombaire diagnostiqué tardivement. Nous avons également réalisé une revue de la littérature pour résumer les principaux critères diagnostiques et les modalités de prise en charge.
Morphologie, 2015
Introduction L’evolution technologique en neurochirurgie a permis le developpement de systeme de ... more Introduction L’evolution technologique en neurochirurgie a permis le developpement de systeme de magnification de plus en plus performant. C’est le cas des microscopes operatoires et de l’endoscopie. L’endoscopie 3D VisionSense ® est actuellement disponible. Nous avons souhaite montrer l’utilisation de cette nouvelle technologie dans le cas du traitement des fistules arterio-veineuses (FAV). Materiel et methode Nous presentons 3 cas de FAV, 2 cas de FAV medullaire thoracique et un cas de FAV de fosse posterieure. Dans les trois cas le traitement a ete chirurgical, exclusivement sous endoscopie 3D. L’analyse peroperatoire de l’anatomie est presentee sous forme de video. Resultats Une fois exposee, dans chaque cas la fistule a pu etre aisement exclue sous magnification avec l’endoscope 3D. L’intervention s’est deroulee sans incident et les suites operatoires ont ete marquees par une amelioration clinique. Les angiographies ont confirme l’exclusion de la fistule durale. Conclusion L’endoscopie 3D permet une magnification importante tout en preservant la profondeur de champ pour une excellente visualisation et appreciation des rapports vasculaires et nerveux. Dans le cas d’une fistule durale l’exploration est facilitee en raison de la maniabilite de l’optique, contrairement au microscope.