Study Design-In vitro experiment using human intervertebral disc (IVD) cells and adenovirustherap... more Study Design-In vitro experiment using human intervertebral disc (IVD) cells and adenovirustherapeutic gene constructs. Objectives-To examine the biologic effect of "cocktail" therapeutic gene transfer to human IVD cells in three dimensional cultures. Summary of Background Data-. Gene therapy is regarded as a potential option for the treatment of degenerative disc disease. Although various anabolic genes have previously been introduced for this purpose, cocktail gene transfer of anabolic genes to IVD cells has never been attempted. Materials and Methods-Human IVDs were harvested during surgical disc procedures and cultured. We prepared recombinant adenovirus constructs bearing the TGF-β1 gene (Ad/TGF-β1), the IGF-1 gene (Ad/IGF-1), and the BMP-2 gene (Ad/BMP-2). Transgene expression was detected by luciferase assays, enzyme linked immuno-sorbent assays, and Western blot analysis. Newly synthesized proteoglycan was measured by 35 S-sulfate incorporation on Sephadex G-25M in PD 10 columns. Human IVD cells were transduced by single, double, and triple combination of Ad/TGF-β1, Ad/IGF-1, Ad/BMP-2 with an MOI of 75, then cultured three-dimensionally in alginate beads. Results-Transgene expression was detected at 18 hours after viral transduction. IVD cultures with Ad/TGF-β1, Ad/IGF-1, Ad/BMP-2 (MOI of 75) showed 2.9, 1.8, and 1.9 fold increases, respectively, in proteoglycan synthesis compared to control. Human IVD cultures with double gene combination (MOI of 75) showed 3.2 to 3.9 fold increases of proteoglycan synthesis. Lastly, Human IVD cultures with triple gene combination (TGF-β1+IGF-1+BMP-2 genes with an MOI of 75) transfer demonstrated 4.7 fold increase in proteoglycan synthesis compared control. Conclusion-Combination or "cocktail" gene therapy offers a promising mechanism for maximizing matrix synthesis with low dose of adenoviral mixtures, circumventing systemic, local toxic effect, and immune response.
Purpose-The loss of nutrient supply is a suspected contributor of intervertebral disc degeneratio... more Purpose-The loss of nutrient supply is a suspected contributor of intervertebral disc degeneration. However, the extent to which low nutrition affects disc annulus fibrosus (AF) cells is unknown as nutrient deprivation has mainly been investigated in disc nucleus pulposus cells. Hence, an experimental study was designed to clarify effects of limited nutrients on disc AF cell fate, including autophagy, the process by which cells recycle their own damaged components. Methods-Rabbit disc AF cells were cultured in different media with varying serum concentrations under 5% oxygen. Cellular responses to changes in serum and nutrient
Surgery is a major challenge for the immune system, but little is known about the immune response... more Surgery is a major challenge for the immune system, but little is known about the immune response of geriatric patients to surgery. We therefore investigated the impact of surgery on the molecular signature of circulating CD14+ monocytes, cells implicated in clinical recovery from surgery, in older patients. We enrolled older patients having elective joint replacement (N = 19) or spine (N = 16) surgery and investigated pre- to postoperative expression changes in 784 immune-related genes in monocytes. Joint replacement altered the expression of 489 genes (adjusted p < 0.05), of which 38 had a |logFC| > 1. Spine surgery changed the expression of 209 genes (adjusted p < 0.05), of which 27 had a |logFC| > 1. In both, the majority of genes with a |logFC| > 1 change were downregulated. In the combined group (N = 35), 471 transcripts were differentially expressed (adjusted p < 0.05) after surgery; 29 had a |logFC| > 1 and 72% of these were downregulated. Notably, 21 tr...
Background Frailty and cognitive impairment are associated with postoperative delirium, but are r... more Background Frailty and cognitive impairment are associated with postoperative delirium, but are rarely assessed preoperatively. The study was designed to test the hypothesis that preoperative screening for frailty or cognitive impairment identifies patients at risk for postoperative delirium (primary outcome). Methods In this prospective cohort study, the authors administered frailty and cognitive screening instruments to 229 patients greater than or equal to 70 yr old presenting for elective spine surgery. Screening for frailty (five-item FRAIL scale [measuring fatigue, resistance, ambulation, illness, and weight loss]) and cognition (Mini-Cog, Animal Verbal Fluency) were performed at the time of the preoperative evaluation. Demographic data, perioperative variables, and postoperative outcomes were gathered. Delirium was the primary outcome detected by either the Confusion Assessment Method, assessed daily from postoperative day 1 to 3 or until discharge, if patient was discharged ...
BackgroundIntervertebral disc degeneration contributes to low back pain. The avascular interverte... more BackgroundIntervertebral disc degeneration contributes to low back pain. The avascular intervertebral disc consists of a central hypoxic nucleus pulpous (NP) surrounded by the more oxygenated annulus fibrosus (AF). Lactate, an abundant end-product of NP glycolysis, has long been viewed as a harmful waste that acidifies disc tissue and decreases cell viability and function. The objective of this study was to determine whether lactate could be used by AF cells as a carbon source rather than being removed from disc tissue as a waste byproduct.Methods.Import and conversion of lactate to tricarboxylic acid (TCA) cycle intermediates and amino acids in rabbit AF cells were measured by heavy-isotope (13C-lactate) tracing experiments using mass spectrometry. Levels of protein expression of lactate converting enzymes, lactate importer and exporter in NP and AF tissues were quantified by Western blots. Effects of lactate on proteoglycan (35S-sulfate) and collagen (3H-proline) matrix protein sy...
Intervertebral disc degeneration (IDD) has a greater than 90% lifetime incidence and is one of th... more Intervertebral disc degeneration (IDD) has a greater than 90% lifetime incidence and is one of the leading causes of chronic back pain in the U.S. Despite the high societal cost of IDD, there is limited understanding of the biological effects of mechanical overloading on further degeneration. The transcription factor NF-κB has been implicated as a key mediator of disc cell response to inflammatory and mechanical stresses and represents a potential control point. The study objective was to measure the effect of NF-κB signaling pathway inhibition on annulus fibrosus (AF) cell matrix synthesis and gene expression under conditions of combined inflammatory and mechanical stimulation. AF cells were harvested from rabbit intervertebral discs and grown in vitro on Flexcell plates. The cells were exposed to inflammatory and mechanical stimulation for 24 hours with and without NF-κB inhibition. Nuclear translocation of NF-κB was measured via immunofluorescent staining. Intervertebral disc cel...
Objective: To investigate the effects of proteins products of endothelial cells (ECs) on the annu... more Objective: To investigate the effects of proteins products of endothelial cells (ECs) on the annulus fibrosus (AF) cell metabolism in an in vitro culture. Methods: Human AF cells were expanded in monolayer cultures and treated with proteins from the medium of cell line HMEC-1 (Human Microvascular Endothelial Cells) (125μg/ml). After 72h of treatment RNA was isolated from AF cells for analysis of gene expression and the culture medium was collected for protein expression analysis. Results: The qRT-PCR analysis demonstrated increased gene expression of matrix metalloproteinases (MMPs) in AF cells treated with protein products of endothelial cells compared with cells from control group of AF cells: MMP-1 243.10 times (p<0.05), MMP-2 1.37 time (p<0.05), MMP-3 39.83 times (p<0.05) and MMP-13 5.70 times (p<0.05). In contrast, tissue inhibitors of metalloproteinases (TIMPs) were suppressed; TIMP-2 (0.55 time) (p<0.05) and TIMP-3 (0.60 time) (p<0.05) in the exposed groups. The expression of aggrecan gene (0.83 time) (p<0.05), an important extracellular matrix component, was also reduced. MMP-1 and MMP-3 detection was performed, confirming the results of PCR by Western Blot technique. Conclusions: In this study, we observed that the proteins produced by ECs induced the MMPs expression and suppressed the TIMPs as well as the aggrecan in primary cells of the human intervertebral disc, targeting the development of potential treatments for intervertebral disc degeneration and associated discogenic pain.
Part of the Orthopedics Commons This Article is brought to you for free and open access by the Je... more Part of the Orthopedics Commons This Article is brought to you for free and open access by the Jefferson Digital Commons. The Jefferson Digital Commons is a service of Thomas Jefferson University's Center for Teaching and Learning (CTL). The Commons is a showcase for Jefferson books and journals, peer-reviewed scholarly publications, unique historical collections from the University archives, and teaching tools. The Jefferson Digital Commons allows researchers and interested readers anywhere in the world to learn about and keep up to date with Jefferson scholarship. This article has been accepted for inclusion in Department of Orthopaedic Surgery Faculty Papers by an authorized administrator of the Jefferson Digital Commons.
Symptomatic adjacent segment disease (ASD) after anterior cervical fusion (ACF) is reported in 25... more Symptomatic adjacent segment disease (ASD) after anterior cervical fusion (ACF) is reported in 25% of patients at 10 years postoperatively. Debate continues as to whether this degeneration is due to the natural history of the disk or the changed biomechanics after ACF. This study explored whether congenital stenosis predisposes patients to an increased incidence of ASD after ACF. A retrospective review of 635 patients with myelopathy or radiculopathy was performed; 364 patients had complete records for review. Patients underwent 1- to 5-level ACF (94 one-level, 145 two-level, 79 three-level, 45 four-level, and 1 five-level). Radiographs were evaluated for bony congenital stenosis using validated parameters, and ASD was measured according to Hilibrand’s criteria and correlated with symptomatic ASD. Congenital stenosis was found in 21.7% of patients and radiographic ASD in 33.5%, with a significant association between these parameters. However, symptomatic ASD occurred in 11.8% of pat...
liable to prosecution. This applies in particular to photostat reproduction, copying, mimeographi... more liable to prosecution. This applies in particular to photostat reproduction, copying, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage. Important note: Medical knowledge is ever-changing. As new research and clinical experience broaden our knowledge, changes in treatment and drug therapy may be required. The authors and editors of the material herein have consulted sources believed to be reliable in their efforts to provide information that is complete and in accord with the standards accepted at the time of publication. However, in view of the possibility of human error by the authors, editors, or publisher of the work herein or changes in medical knowledge, neither the authors, editors, nor publisher, nor any other party who has been involved in the preparation of this work, warrants that the information contained herein is in every respect accurate or complete, and they are not responsible for any errors or omissions or for the results obtained from use of such information. Readers are encouraged to confirm the information contained herein with other sources. For example, readers are advised to check the product information sheet included in the package of each drug they plan to administer to be certain that the information contained in this publication is accurate and that changes have not been made in the recommended dose or in the contraindications for administration. This recommendation is of particular importance in connection with new or infrequently used drugs. Some of the product names, patents, and registered designs referred to in this book are in fact registered trademarks or proprietary names even though specific reference to this fact is not always made in the text. Therefore, the appearance of a name without designation as proprietary is not to be construed as a representation by the publisher that it is in the public domain.
BACKGROUND CONTEXT: Although previous studies have primarily focused on testing the effectiveness... more BACKGROUND CONTEXT: Although previous studies have primarily focused on testing the effectiveness of cervical orthoses under properly fit conditions, this study focuses on analyzing the effects of an ill-fitted cervical orthoses (Miami J). This may have significance to health-care providers in understanding the effects of an improperly fitted neck brace. PURPOSE: The aims of this study were threefold: first, to apply virtual reality (VR) feedback control to repeatedly measure orthoses effectiveness in the primary motions; second, to use this control methodology to test the orthoses ability to restrict flexion/extension (FE) as a function of axial rotation (AR); third, to test the effects of an ill-fitting Miami J on cervical motion.
Background The authors describe their experience with the choice of anterior, posterior and combi... more Background The authors describe their experience with the choice of anterior, posterior and combined approaches for the surgical treatment of spondylotic myelopathy. Methods Description of surgical anatomy, surgical technique, indications, limitations, complications, specific perioperative considerations and specific information to give to the patient about surgery and potential risks and a summary of 10 key points is given. Conclusions If the disease extends behind the posterior vertebral body and if reestablishing spinal sagittal and coronal balance is an aim, then the anterior approach is the best choice. In cases of predominant posterior spinal cord compression and lordotic configuration the posterior approach should be preferred. Decompression of three or more levels, especially in combination with poor bone quality, requires a combined approach.
ADAMTS5-deficient and WT mice were chronically exposed to tobacco smoke to investigate effects on... more ADAMTS5-deficient and WT mice were chronically exposed to tobacco smoke to investigate effects on intervertebral disc degeneration (IDD). To demonstrate a role for ADAMTS5 in mediating tobacco smoking-induced IDD SUMMARY OF BACKGROUND DATA.: We previously demonstrated that chronic tobacco smoking causes IDD in mice due, in part, to proteolytic destruction of disc aggrecan. However, it was unknown which matrix proteinase(s) drive these detrimental effects. Three-month old Wt (C57BL/6) and ADAMTS5 mice were chronically exposed to tobacco smoke (4 cigarettes/day, 5 day/week for 6 months). ADAMTS-mediated cleavage of disc aggrecan was analyzed by Western blot. Disc total glycosaminoglycan (GAG) content was assessed by dimethyl methylene blue assay and safranin O/fast green histology. Vertebral osteoporosity was measured by micro-computed tomography. Human nucleus pulposus (hNP) cell cultures were also exposed directly to tobacco smoke extract (TSE), a condensate containing the water-sol...
Background: Vertebral artery injuries during cervical spine surgery are rare, but potentially fat... more Background: Vertebral artery injuries during cervical spine surgery are rare, but potentially fatal. When performing cervical spine surgery, it is imperative that the surgeon has a systematic approach for avoiding, and if necessary, dealing with a vertebral artery injury. Methods: This is a review paper. Results: Upper posterior cervical spine surgeries put the vertebral artery at the highest risk, as opposed to anterior subaxial cervical spine procedures, which put the artery at the least risk. A thorough understanding of the complex anatomy of the vertebral artery is mandatory prior to performing cervical spine surgery, and since the vertebral artery can have a variable course, especially in the upper cervical spine, the surgeon must minimize the possibility of an arterial injury by preoperatively assessing the artery with a computed tomography (CT) scan or magnetic resonance imaging (MRI). Intraoperatively, the surgeon must be aware of when the vertebral artery is most at risk, and take precautions to avoid an injury. In the event of an arterial injury, the surgeon must have a plan of action to (1) Achieve control of the hemorrhage. (2) Prevent acute central nervous system ischemia. (3) Prevent postoperative complications such as embolism and pseudoaneurysm Conclusion: Prior to performing cervical spine surgery, one must understand the four A's of vertebral artery injuries: Anatomy, Assessment, Avoidance, and Action.
The Journal of bone and joint surgery. American volume, Jan 2, 2017
There is a growing concern that the use of prescription opioids following surgical interventions,... more There is a growing concern that the use of prescription opioids following surgical interventions, including spine surgery, may predispose patients to chronic opioid use and abuse. We sought to estimate the proportion of patients using opioids up to 1 year after discharge following common spinal surgical procedures and to identify factors associated with sustained opioid use. This study utilized 2006 to 2014 data from TRICARE insurance claims obtained from the Military Health System Data Repository. Adults who underwent 1 of 4 common spinal surgical procedures (discectomy, decompression, lumbar posterolateral arthrodesis, or lumbar interbody arthrodesis) were identified. Patients with a history of opioid use in the 6 months preceding surgery were excluded. Posterolateral arthrodesis and interbody arthrodesis were considered procedures of high intensity, and discectomy and decompression, low intensity. Covariates included demographic factors, preoperative diagnoses, comorbidities, pos...
Adult patients who received CT alone or CT-MRI for the evaluation of cervical OBJECTIVE.: To eval... more Adult patients who received CT alone or CT-MRI for the evaluation of cervical OBJECTIVE.: To evaluate the utility of CT-MRI in the diagnosis of cervical spine injury using propensity matched techniques. The optimal evaluation (computed tomography [CT] alone vs CT and magnetic resonance imaging [MRI]) for patients with suspected cervical spine injury in the setting of blunt trauma remains controversial. The primary outcome was the identification of a cervical spine injury, with decision for surgery and change in management considered secondarily. A propensity score was developed based on the likelihood of receiving evaluation with CT-MRI and this score was used to balance the cohorts and develop two groups of patients around whom there was a degree of clinical equipoise in terms of the imaging protocol. Logistic regression was used to evaluate for significant differences in injury detection in patients evaluated with CT alone as compared to those receiving CT-MRI. Between 2007-2014 8...
Study Design-In vitro experiment using human intervertebral disc (IVD) cells and adenovirustherap... more Study Design-In vitro experiment using human intervertebral disc (IVD) cells and adenovirustherapeutic gene constructs. Objectives-To examine the biologic effect of "cocktail" therapeutic gene transfer to human IVD cells in three dimensional cultures. Summary of Background Data-. Gene therapy is regarded as a potential option for the treatment of degenerative disc disease. Although various anabolic genes have previously been introduced for this purpose, cocktail gene transfer of anabolic genes to IVD cells has never been attempted. Materials and Methods-Human IVDs were harvested during surgical disc procedures and cultured. We prepared recombinant adenovirus constructs bearing the TGF-β1 gene (Ad/TGF-β1), the IGF-1 gene (Ad/IGF-1), and the BMP-2 gene (Ad/BMP-2). Transgene expression was detected by luciferase assays, enzyme linked immuno-sorbent assays, and Western blot analysis. Newly synthesized proteoglycan was measured by 35 S-sulfate incorporation on Sephadex G-25M in PD 10 columns. Human IVD cells were transduced by single, double, and triple combination of Ad/TGF-β1, Ad/IGF-1, Ad/BMP-2 with an MOI of 75, then cultured three-dimensionally in alginate beads. Results-Transgene expression was detected at 18 hours after viral transduction. IVD cultures with Ad/TGF-β1, Ad/IGF-1, Ad/BMP-2 (MOI of 75) showed 2.9, 1.8, and 1.9 fold increases, respectively, in proteoglycan synthesis compared to control. Human IVD cultures with double gene combination (MOI of 75) showed 3.2 to 3.9 fold increases of proteoglycan synthesis. Lastly, Human IVD cultures with triple gene combination (TGF-β1+IGF-1+BMP-2 genes with an MOI of 75) transfer demonstrated 4.7 fold increase in proteoglycan synthesis compared control. Conclusion-Combination or "cocktail" gene therapy offers a promising mechanism for maximizing matrix synthesis with low dose of adenoviral mixtures, circumventing systemic, local toxic effect, and immune response.
Purpose-The loss of nutrient supply is a suspected contributor of intervertebral disc degeneratio... more Purpose-The loss of nutrient supply is a suspected contributor of intervertebral disc degeneration. However, the extent to which low nutrition affects disc annulus fibrosus (AF) cells is unknown as nutrient deprivation has mainly been investigated in disc nucleus pulposus cells. Hence, an experimental study was designed to clarify effects of limited nutrients on disc AF cell fate, including autophagy, the process by which cells recycle their own damaged components. Methods-Rabbit disc AF cells were cultured in different media with varying serum concentrations under 5% oxygen. Cellular responses to changes in serum and nutrient
Surgery is a major challenge for the immune system, but little is known about the immune response... more Surgery is a major challenge for the immune system, but little is known about the immune response of geriatric patients to surgery. We therefore investigated the impact of surgery on the molecular signature of circulating CD14+ monocytes, cells implicated in clinical recovery from surgery, in older patients. We enrolled older patients having elective joint replacement (N = 19) or spine (N = 16) surgery and investigated pre- to postoperative expression changes in 784 immune-related genes in monocytes. Joint replacement altered the expression of 489 genes (adjusted p < 0.05), of which 38 had a |logFC| > 1. Spine surgery changed the expression of 209 genes (adjusted p < 0.05), of which 27 had a |logFC| > 1. In both, the majority of genes with a |logFC| > 1 change were downregulated. In the combined group (N = 35), 471 transcripts were differentially expressed (adjusted p < 0.05) after surgery; 29 had a |logFC| > 1 and 72% of these were downregulated. Notably, 21 tr...
Background Frailty and cognitive impairment are associated with postoperative delirium, but are r... more Background Frailty and cognitive impairment are associated with postoperative delirium, but are rarely assessed preoperatively. The study was designed to test the hypothesis that preoperative screening for frailty or cognitive impairment identifies patients at risk for postoperative delirium (primary outcome). Methods In this prospective cohort study, the authors administered frailty and cognitive screening instruments to 229 patients greater than or equal to 70 yr old presenting for elective spine surgery. Screening for frailty (five-item FRAIL scale [measuring fatigue, resistance, ambulation, illness, and weight loss]) and cognition (Mini-Cog, Animal Verbal Fluency) were performed at the time of the preoperative evaluation. Demographic data, perioperative variables, and postoperative outcomes were gathered. Delirium was the primary outcome detected by either the Confusion Assessment Method, assessed daily from postoperative day 1 to 3 or until discharge, if patient was discharged ...
BackgroundIntervertebral disc degeneration contributes to low back pain. The avascular interverte... more BackgroundIntervertebral disc degeneration contributes to low back pain. The avascular intervertebral disc consists of a central hypoxic nucleus pulpous (NP) surrounded by the more oxygenated annulus fibrosus (AF). Lactate, an abundant end-product of NP glycolysis, has long been viewed as a harmful waste that acidifies disc tissue and decreases cell viability and function. The objective of this study was to determine whether lactate could be used by AF cells as a carbon source rather than being removed from disc tissue as a waste byproduct.Methods.Import and conversion of lactate to tricarboxylic acid (TCA) cycle intermediates and amino acids in rabbit AF cells were measured by heavy-isotope (13C-lactate) tracing experiments using mass spectrometry. Levels of protein expression of lactate converting enzymes, lactate importer and exporter in NP and AF tissues were quantified by Western blots. Effects of lactate on proteoglycan (35S-sulfate) and collagen (3H-proline) matrix protein sy...
Intervertebral disc degeneration (IDD) has a greater than 90% lifetime incidence and is one of th... more Intervertebral disc degeneration (IDD) has a greater than 90% lifetime incidence and is one of the leading causes of chronic back pain in the U.S. Despite the high societal cost of IDD, there is limited understanding of the biological effects of mechanical overloading on further degeneration. The transcription factor NF-κB has been implicated as a key mediator of disc cell response to inflammatory and mechanical stresses and represents a potential control point. The study objective was to measure the effect of NF-κB signaling pathway inhibition on annulus fibrosus (AF) cell matrix synthesis and gene expression under conditions of combined inflammatory and mechanical stimulation. AF cells were harvested from rabbit intervertebral discs and grown in vitro on Flexcell plates. The cells were exposed to inflammatory and mechanical stimulation for 24 hours with and without NF-κB inhibition. Nuclear translocation of NF-κB was measured via immunofluorescent staining. Intervertebral disc cel...
Objective: To investigate the effects of proteins products of endothelial cells (ECs) on the annu... more Objective: To investigate the effects of proteins products of endothelial cells (ECs) on the annulus fibrosus (AF) cell metabolism in an in vitro culture. Methods: Human AF cells were expanded in monolayer cultures and treated with proteins from the medium of cell line HMEC-1 (Human Microvascular Endothelial Cells) (125μg/ml). After 72h of treatment RNA was isolated from AF cells for analysis of gene expression and the culture medium was collected for protein expression analysis. Results: The qRT-PCR analysis demonstrated increased gene expression of matrix metalloproteinases (MMPs) in AF cells treated with protein products of endothelial cells compared with cells from control group of AF cells: MMP-1 243.10 times (p<0.05), MMP-2 1.37 time (p<0.05), MMP-3 39.83 times (p<0.05) and MMP-13 5.70 times (p<0.05). In contrast, tissue inhibitors of metalloproteinases (TIMPs) were suppressed; TIMP-2 (0.55 time) (p<0.05) and TIMP-3 (0.60 time) (p<0.05) in the exposed groups. The expression of aggrecan gene (0.83 time) (p<0.05), an important extracellular matrix component, was also reduced. MMP-1 and MMP-3 detection was performed, confirming the results of PCR by Western Blot technique. Conclusions: In this study, we observed that the proteins produced by ECs induced the MMPs expression and suppressed the TIMPs as well as the aggrecan in primary cells of the human intervertebral disc, targeting the development of potential treatments for intervertebral disc degeneration and associated discogenic pain.
Part of the Orthopedics Commons This Article is brought to you for free and open access by the Je... more Part of the Orthopedics Commons This Article is brought to you for free and open access by the Jefferson Digital Commons. The Jefferson Digital Commons is a service of Thomas Jefferson University's Center for Teaching and Learning (CTL). The Commons is a showcase for Jefferson books and journals, peer-reviewed scholarly publications, unique historical collections from the University archives, and teaching tools. The Jefferson Digital Commons allows researchers and interested readers anywhere in the world to learn about and keep up to date with Jefferson scholarship. This article has been accepted for inclusion in Department of Orthopaedic Surgery Faculty Papers by an authorized administrator of the Jefferson Digital Commons.
Symptomatic adjacent segment disease (ASD) after anterior cervical fusion (ACF) is reported in 25... more Symptomatic adjacent segment disease (ASD) after anterior cervical fusion (ACF) is reported in 25% of patients at 10 years postoperatively. Debate continues as to whether this degeneration is due to the natural history of the disk or the changed biomechanics after ACF. This study explored whether congenital stenosis predisposes patients to an increased incidence of ASD after ACF. A retrospective review of 635 patients with myelopathy or radiculopathy was performed; 364 patients had complete records for review. Patients underwent 1- to 5-level ACF (94 one-level, 145 two-level, 79 three-level, 45 four-level, and 1 five-level). Radiographs were evaluated for bony congenital stenosis using validated parameters, and ASD was measured according to Hilibrand’s criteria and correlated with symptomatic ASD. Congenital stenosis was found in 21.7% of patients and radiographic ASD in 33.5%, with a significant association between these parameters. However, symptomatic ASD occurred in 11.8% of pat...
liable to prosecution. This applies in particular to photostat reproduction, copying, mimeographi... more liable to prosecution. This applies in particular to photostat reproduction, copying, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage. Important note: Medical knowledge is ever-changing. As new research and clinical experience broaden our knowledge, changes in treatment and drug therapy may be required. The authors and editors of the material herein have consulted sources believed to be reliable in their efforts to provide information that is complete and in accord with the standards accepted at the time of publication. However, in view of the possibility of human error by the authors, editors, or publisher of the work herein or changes in medical knowledge, neither the authors, editors, nor publisher, nor any other party who has been involved in the preparation of this work, warrants that the information contained herein is in every respect accurate or complete, and they are not responsible for any errors or omissions or for the results obtained from use of such information. Readers are encouraged to confirm the information contained herein with other sources. For example, readers are advised to check the product information sheet included in the package of each drug they plan to administer to be certain that the information contained in this publication is accurate and that changes have not been made in the recommended dose or in the contraindications for administration. This recommendation is of particular importance in connection with new or infrequently used drugs. Some of the product names, patents, and registered designs referred to in this book are in fact registered trademarks or proprietary names even though specific reference to this fact is not always made in the text. Therefore, the appearance of a name without designation as proprietary is not to be construed as a representation by the publisher that it is in the public domain.
BACKGROUND CONTEXT: Although previous studies have primarily focused on testing the effectiveness... more BACKGROUND CONTEXT: Although previous studies have primarily focused on testing the effectiveness of cervical orthoses under properly fit conditions, this study focuses on analyzing the effects of an ill-fitted cervical orthoses (Miami J). This may have significance to health-care providers in understanding the effects of an improperly fitted neck brace. PURPOSE: The aims of this study were threefold: first, to apply virtual reality (VR) feedback control to repeatedly measure orthoses effectiveness in the primary motions; second, to use this control methodology to test the orthoses ability to restrict flexion/extension (FE) as a function of axial rotation (AR); third, to test the effects of an ill-fitting Miami J on cervical motion.
Background The authors describe their experience with the choice of anterior, posterior and combi... more Background The authors describe their experience with the choice of anterior, posterior and combined approaches for the surgical treatment of spondylotic myelopathy. Methods Description of surgical anatomy, surgical technique, indications, limitations, complications, specific perioperative considerations and specific information to give to the patient about surgery and potential risks and a summary of 10 key points is given. Conclusions If the disease extends behind the posterior vertebral body and if reestablishing spinal sagittal and coronal balance is an aim, then the anterior approach is the best choice. In cases of predominant posterior spinal cord compression and lordotic configuration the posterior approach should be preferred. Decompression of three or more levels, especially in combination with poor bone quality, requires a combined approach.
ADAMTS5-deficient and WT mice were chronically exposed to tobacco smoke to investigate effects on... more ADAMTS5-deficient and WT mice were chronically exposed to tobacco smoke to investigate effects on intervertebral disc degeneration (IDD). To demonstrate a role for ADAMTS5 in mediating tobacco smoking-induced IDD SUMMARY OF BACKGROUND DATA.: We previously demonstrated that chronic tobacco smoking causes IDD in mice due, in part, to proteolytic destruction of disc aggrecan. However, it was unknown which matrix proteinase(s) drive these detrimental effects. Three-month old Wt (C57BL/6) and ADAMTS5 mice were chronically exposed to tobacco smoke (4 cigarettes/day, 5 day/week for 6 months). ADAMTS-mediated cleavage of disc aggrecan was analyzed by Western blot. Disc total glycosaminoglycan (GAG) content was assessed by dimethyl methylene blue assay and safranin O/fast green histology. Vertebral osteoporosity was measured by micro-computed tomography. Human nucleus pulposus (hNP) cell cultures were also exposed directly to tobacco smoke extract (TSE), a condensate containing the water-sol...
Background: Vertebral artery injuries during cervical spine surgery are rare, but potentially fat... more Background: Vertebral artery injuries during cervical spine surgery are rare, but potentially fatal. When performing cervical spine surgery, it is imperative that the surgeon has a systematic approach for avoiding, and if necessary, dealing with a vertebral artery injury. Methods: This is a review paper. Results: Upper posterior cervical spine surgeries put the vertebral artery at the highest risk, as opposed to anterior subaxial cervical spine procedures, which put the artery at the least risk. A thorough understanding of the complex anatomy of the vertebral artery is mandatory prior to performing cervical spine surgery, and since the vertebral artery can have a variable course, especially in the upper cervical spine, the surgeon must minimize the possibility of an arterial injury by preoperatively assessing the artery with a computed tomography (CT) scan or magnetic resonance imaging (MRI). Intraoperatively, the surgeon must be aware of when the vertebral artery is most at risk, and take precautions to avoid an injury. In the event of an arterial injury, the surgeon must have a plan of action to (1) Achieve control of the hemorrhage. (2) Prevent acute central nervous system ischemia. (3) Prevent postoperative complications such as embolism and pseudoaneurysm Conclusion: Prior to performing cervical spine surgery, one must understand the four A's of vertebral artery injuries: Anatomy, Assessment, Avoidance, and Action.
The Journal of bone and joint surgery. American volume, Jan 2, 2017
There is a growing concern that the use of prescription opioids following surgical interventions,... more There is a growing concern that the use of prescription opioids following surgical interventions, including spine surgery, may predispose patients to chronic opioid use and abuse. We sought to estimate the proportion of patients using opioids up to 1 year after discharge following common spinal surgical procedures and to identify factors associated with sustained opioid use. This study utilized 2006 to 2014 data from TRICARE insurance claims obtained from the Military Health System Data Repository. Adults who underwent 1 of 4 common spinal surgical procedures (discectomy, decompression, lumbar posterolateral arthrodesis, or lumbar interbody arthrodesis) were identified. Patients with a history of opioid use in the 6 months preceding surgery were excluded. Posterolateral arthrodesis and interbody arthrodesis were considered procedures of high intensity, and discectomy and decompression, low intensity. Covariates included demographic factors, preoperative diagnoses, comorbidities, pos...
Adult patients who received CT alone or CT-MRI for the evaluation of cervical OBJECTIVE.: To eval... more Adult patients who received CT alone or CT-MRI for the evaluation of cervical OBJECTIVE.: To evaluate the utility of CT-MRI in the diagnosis of cervical spine injury using propensity matched techniques. The optimal evaluation (computed tomography [CT] alone vs CT and magnetic resonance imaging [MRI]) for patients with suspected cervical spine injury in the setting of blunt trauma remains controversial. The primary outcome was the identification of a cervical spine injury, with decision for surgery and change in management considered secondarily. A propensity score was developed based on the likelihood of receiving evaluation with CT-MRI and this score was used to balance the cohorts and develop two groups of patients around whom there was a degree of clinical equipoise in terms of the imaging protocol. Logistic regression was used to evaluate for significant differences in injury detection in patients evaluated with CT alone as compared to those receiving CT-MRI. Between 2007-2014 8...
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