- Email: [email protected]
166. Can C7 slope be used as a substitute for T1 slope? A radiographic analysis
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Proceedings of the 34th Annual Meeting of the North American Spine Society / The Spine Journal 19 (2019) S59−S100
STUDY DESIGN/SETTING: Multicenter review of single institutional case series. PATIENT SAMPLE: Patients under the age of 18 years who had been treated operatively for a thoracolumbar fracture between 2006 and 2016 were identified. Inclusion criteria included patients with preinjury computed tomography (CT) scans and magnetic resonance imaging (MRI) and who were less than 18 years of age. OUTCOME MEASURES: Classification through AOSpine Thoracolumbar Spine Injury Classification System METHODS: A group of nine POSNA (Pediatric Orthopaedic Society of North America) member surgeons were sent an electronic link containing educational videos and schematic papers describing the AOSpine Thoracolumbar Spine Injury Classification System. The link also contained MRI (magnetic resonance imaging) and CT (computed tomography) imaging of 25 pediatric patients with thoracolumbar spine injuries organized into cases to review and classify. The evaluators classified injuries into 3 primary categories: A, B, and C. Interobserver reliability was assessed for the initial reading across all 9 raters by Fleiss’s kappa coefficient (kF) along with 95% confidence intervals (CI). For A and B type injuries, subclassification was conducted including A0-A4 and B1-B2 subtypes. Interobserver reliability across subclasses was assessed using Krippendorff’s alpha (ak) along with bootstrapped 95% CIs. Imaging was reviewed a second time by all 9 evaluators approximately one month from the initial read. All patient imaging was blinded and randomized for each read independently. Intraobserver reproducibility was assessed for the primary classifications using Fleiss’s kappa and subclassification reproducibility was assessed by Krippendorff’s alpha (ak) along with 95% CIs. Interpretations for reliability estimates were based on Landis and Koch (1977): 0-0.2, slight; 0.2-0.4, fair; 0.4-0.6, moderate; 0.6-0.8, substantial; and >0.8, almost perfect agreement. RESULTS: Twenty-five cases were read by 9 raters for a total of 225 initial and 225 repeated evaluations. Interobserver reliability was almost perfect (kF = 0.82; CI = 0.77 - 0.87) across all 9 raters. Subclassification reliability was substantial (aK = 0.79; CI = 0.62 - 0.90). Intraobserver reproducibility was almost perfect (kF= 0.81; CI = 0.71 - 0.90) for both primary classifications and for subclassifications (ak = 0.81; CI = 0.73 - 0.86). CONCLUSIONS: The reliability for the AOSpine classification system was high amongst POSNA surgeons when applied to pediatric patients. Given a lack of a uniform classification in the pediatric population, the AOSpine Thoracolumbar Spine Injury Classification System has the potential to be used as the first universal spine fracture classification in children. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.181
165. Transverse pedicle angle is associated with pelvic incidence and increased in isthmic spondylolisthesis Atticus C. Coscia, BS1, Matthew R. Coscia, BA2, Erin C. Coscia, BA4, Michael B. Hostetter, MD3, Kevin O’Neill, MD2, Curtis Ramsey4, Michael F. Coscia, MD2; 1 Zionsville, IN, US; 2 Wake Forest University School of Medicine, Indianapolis, IN, USA; 3 CDI, Carmel, IN, US; 4 OrthoIndy, Indianapolis, IN, USA BACKGROUND CONTEXT: We examined lumbar transverse pedicle angle (TPA) in relation to pelvic incidence (PI) and made comparisons between patients with degenerative spondylolisthesis (DS), isthmic spondylolisthesis (IS), and controls. Higher PI was associated with increased TPA. TPA was similar between DS and controls but was significantly higher in IS compared to both DS and controls. This study is the first to demonstrate an association between TPA and PI, and the first to demonstrate a difference in transverse vertebral anatomy in IS. PURPOSE: We hypothesized that a larger TPA would be associated a higher PI, and that both PI and TPA would be higher in IS compared to controls and DS. STUDY DESIGN/SETTING: Retrospective radiographic review.
PATIENT SAMPLE: Retrospective radiograph analysis performed on 202 patients. Patients were greater than 18 years of age and either had a diagnosis of IS, DS or control. OUTCOME MEASURES: It has been postulated that a higher PI and associated increased lumbar lordosis resulting in increased stress across the pars is a potential causative factor in developing IS. Clinically, we observed an association between IS and increased TPA. The goal of this study was to investigate the potential relationship of TPA to PI, and compare these values between those with IS, DS, and controls. METHODS: A retrospective radiographic analysis was performed on patients greater than 18 years of age having a diagnosis of IS or DS, along with a control group, during the previous 10 years. PI and TPA measurements were made on lateral plane radiographs and CT scans of the lumbar spine. TPA was obtained by measuring the angle between a line perpendicular to the transverse isthmus and a line parallel to the vertebral midline, and was measured at L3-5. RESULTS: There were 202 patients (64 IS, 72 DS, 66 control) included in the study. Interrater reliability showed excellent agreement for PI and TPA (ICC > 0.80). Increasing PI predicted wider TPA across all three vertebral levels for the control group and for L5 in both IS and DS. TPA values for the DS group were not significantly different from controls at any level. However, TPA values (mean§std) for IS (L3: 14§4˚, L4: 17§4˚, L5: 26§ 5˚) were significantly higher than both the DS (L3: 12§3˚, L4: 14§4˚, L5: 22§5˚) and control (L3: 13§4˚, L4: 14§4˚, L5: 21§4˚) groups at all three lumbar vertebral levels measured. CONCLUSIONS: This study is the first to demonstrate an association between TPA and PI, and the first to demonstrate a difference in transverse vertebral anatomy in IS. A wider TPA along with increased PI may result in increased stress at the pars compared to having an increased PI alone, lending further insight into the development of spondylolysis. Further work is warranted to determine the effects of wider TPA and the pathophysiology of IS. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.182 166. Can C7 slope be used as a substitute for T1 slope? A radiographic analysis Ivan B. Ye1, Ray Tang, BA2, Zoe B. Cheung, MD3, Brian Cho, BS4, John Erdman, BA2, John T. Schwartz, BS5, Amir Taree, BA2, Andrew Warburton, BS2, Jun Kim, MD6, Samuel K. Cho, MD2; 1 Mount Sinai School of Medicine, New York, NY, US; 2 New York, NY, US; 3 Mount Sinai Hospital, New York, NY, US; 4 Icahn School of Medicine, New York, NY, US; 5 Icahn School of Medicine at Mount Sinai, New York, NY, US; 6 Mount Sinai Medical Center, New York, NY, US BACKGROUND CONTEXT: Sagittal imbalance in the cervical spine is a major cause of neck pain, headache, fatigue, and disability. While parameters such as C2-C7 lordosis and C2-C7 sagittal vertical axis have been extensively studied, they do not fully characterize cervical sagittal balance. T1 is an important new parameter of both cervical as well as global spinal sagittal balance. However, the T1 superior end plate can be difficult to visualize on standard lateral radiographs due to overlying anatomical structures. C7 slope has therefore been proposed as a potential substitute for T1 slope when the T1 superior end plate is not well visualized. PURPOSE: The objectives of this study were: (1) to assess the correlation between C7 slope and T1 slope on upright lateral cervical spine radiographs, and (2) to evaluate the inter-rater reliability of C7 slope. STUDY DESIGN/SETTING: This was a retrospective cohort study of cervical spine radiographs taken between December 2017 and June 2018 at a single institution. PATIENT SAMPLE: Only radiographs with visible C7 superior and inferior end plates, and T1 superior end plate were included. Radiographs with cervical instrumentation were excluded. OUTCOME MEASURES: Two independent observers measured upper C7 slope, lower C7 slope, and T1 slope.
Refer to onsite annual meeting presentations and postmeeting proceedings for possible referenced figures and tables. Authors are responsible for accurately reporting disclosure and FDA device/drug status at time of abstract submission.
Proceedings of the 34th Annual Meeting of the North American Spine Society / The Spine Journal 19 (2019) S59−S100 METHODS: The correlations between upper C7 slope and T1 slope, as well as between lower C7 slope and T1 slope were evaluated. Linear regression analyses were also performed. Inter-rater reliability of C7 slope as assessed. RESULTS: A total of 650 radiographs were reviewed. The superior end plate of C7, inferior end plate of C7, and superior end plate of T1 were visible in 72.9%, 50.2%, and 31.2% of these radiographs, respectively. After applying our exclusion criteria, 152 patients remained and were included in our analysis. The average age was 48.1 years, with 70.4% females. The average upper C7 slope, lower C7 slope, and T1 slope was 23.5˚§9.1˚, 22.9˚§9.0˚, and 27.5˚§8.7˚, respectively. There was a strong correlation between upper C7 slope and T1 slope (r=0.91, p<0.001), as well as between lower C7 slope and T1 slope (r=0.90, p<0.001). Linear regression analyses showed that T1 slope could be estimated from C7 slope based on the equation, T1 slope = 0.87 x C7 slope + 7, with an overall model fit of R2=0.8. There was strong inter-rater reliability for upper (ICC=0.95, p<0.001) and lower (ICC=0.96, p<0.001) C7 slope. CONCLUSIONS: Both the upper and lower C7 slope are strongly correlated with T1 slope and can be used as a substitute to estimate T1 slope when the superior end plate of T1 is not well visualized. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.183
167. Assessment of the efficacy of teriparatide (Forteo) in patients undergoing posterolateral lumbar spinal fusion: a double-blinded randomized pilot study Shane Burch, MD1, Kevin Taliaferro, MD2, Sigurd H. Berven, MD3, Vedat Deviren, MD1; 1 University of California San Francisco, San Francisco, CA, US; 2 UCSF Medical Center, San francisco, CA, US; 3 UCSF, Dept of Orthopaedic Surgery, San Francisco, CA, US BACKGROUND CONTEXT: Lumbar spinal fusion is an increasingly common procedure for treating degenerative diseases of the lumbar spine. Non-solid fusion, or pseudarthrosis, at one year is a common complication associated with poor clinical outcomes and need for revision surgery. The risk of pseudarthrosis depends on the number of levels fused, the fusion material, and patient risk factors (osteoporosis, smoking, diabetes, etc.). Although there are multiple options for bone graft and osteoinductive materials, all have their benefits, side-effects and cost. Teriparatide is an injectable recombinant analog of parathyroid hormone that has been well-studied in its treatment of osteoporosis. However, no clinical studies of its effect on spinal fusion in humans have been published to date. PURPOSE: To analyze the effect of teriparatide treatment on posterolateral spinal fusion in adults with degenerative diseases of the lumbar spine. STUDY DESIGN/SETTING: Multicenter prospective double-blinded randomized study. PATIENT SAMPLE: 60-90 year-olds with degenerative scoliosis, spondylolisthesis, or spondylosis at two medical centers undergoing instrumented posterolateral instrumented fusion >2levels. Use of BMP was excluded. OUTCOME MEASURES: Pseudoarthrosis, screw loosening, PJK by CT. VAS, ODI, and Eq5D. METHODS: Prospective randomized double-blind placebo-controlled pilot study performed at two large academic centers, UCSF and McGill University (Montreal). Included patients were aged 60-90 years with degenerative lumbar disease who were scheduled to undergo two-level or greater posterolateral lumbar spinal fusion. Patients were randomized in a 2:1 (Forteo:Placebo) manner. Patient were dosed 2 weeks pre-op and 10 weeks post-op. Patient derived outcomes were collected pre-op, 3, 6, 9, and 12 months. Fusions at 1 year were analyzed by helical CT. RESULTS: A total of 36 patients completed the study. 58.3% (n=21) received teriparatide. 42.8% (n=9) reported an adverse event. Fusion rate of all patients was 47.2% (n=17); the remaining 52.8% (n=19) demonstrated pseudoarthrosis at 1 year. Fourty-seven percent of patients
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receiving teriparatide had a pseudoarthrosis, while 60% of placebo had a pseudoarthrosis. VAS, ODI, and Eq5D improved in all groups but no significant difference was found between groups. CONCLUSIONS: Teriparatide appears to provide minimal benefit of avoiding pseudoarthroses in 60-90 year-olds undergoing thoracolumbar fusions. Teriparatide appears to have a fairly safe side effect profile. Further larger scale studies are warranted, possibly with the addition of BMP and/or bisphosphonates. FDA DEVICE/DRUG STATUS: Unavailable from authors at time of publication. https://doi.org/10.1016/j.spinee.2019.05.184
168. Non-viral transfection of human intervertebral disc cells with developmental factors induces reprogramming to a healthy anticatabolic/inflammatory phenotype with enhanced extracellular matrix accumulation Shirley N. Tang, BS1, Justin A. Richards2, Safdar N. Khan, MD3, Judith A. Hoyland4, Daniel Gallego-Perez, PhD1, Natalia Higuita-Castro, PhD1, Benjamin A. Walter, PhD1, Devina Purmessur, PhD (Walter)1; 1 The Ohio State University, Columbus, OH, USA; 2 Columbus, OH, USA; 3 The Ohio State University Wexner Medical Center, Columbus, OH, USA; 4 The University of Manchester, Manchester, United Kingdom BACKGROUND CONTEXT: Intervertebral disc (IVD) degeneration is a significant contributor to low back pain (LBP) and is characterized by a decrease in proteoglycan synthesis, increased catabolism, secretion of inflammatory factors and neurovascular invasion. Although viral gene therapies have been proposed for LBP treatment associated with IVD degeneration, there are concerns due to potential mutagenesis and unwarranted immune responses. To overcome these limitations, nonviral electroporation approaches have been developed. Transcription factor, Brachyury (T) is expressed in the developing notochord and associated with a healthy immature nucleus pulposus (NP) and thus it is a promising factor to reprogram degenerate IVD cells to halt degeneration and promote repair PURPOSE: To examine effects of Ttransfection on human NP cells exvivo. We hypothesize effective delivery of T can reprogram degenerate IVD cells into healthy cells with increased proteoglycan and decreased inflammatory, catabolic and pain factors. STUDY DESIGN/SETTING: 1) Cells isolated from patient and cadaveric human NP tissue. 2) Bulk electroporated with T3) 3D cultured over 4 weeks in agarose gels. PATIENT SAMPLE: N=5 samples from patients undergoing microdiscectomy (painful, 19-70yo) and N=5 cadaveric samples(nonpainful, 1958yo). IRB: 2015H0385 OUTCOME MEASURES: Gene expression (RT-qPCR) for healthy NP phenotypic markers, inflammatory/pain markers, matrix genes, and matrix cleaving enzymes, proteoglycan protein (GAG) (dimethylmethylene blue assay), cell viability (calcein/ethidium staining). METHODS: Cells were enzymatically isolated from NP tissue and expanded. Subsequently, nonpainful (nPT) andpainful (PT) NP cells were electroporated with a plasmids encoding for T, or an empty vector as a SHAM control. The transfected cells were then expanded in disc cell media and seeded in 3D agarose constructs. Outcome measures were examined at day 0, week 2 and week 4. Statistical Mann-Whitney Tests at a=0.05 were used. RESULTS: Cell viability remained high for all groups. Gene expression: healthy marker T was overexpressed and maintained for 4 weeks while KRT19 was significantly increased in nPT and PT cells compared to SHAM controls. Inflammatory cytokines IL-1b and IL6 decreased at 2 weeks for nPT cells and over time for PT cells. Pain marker NGF expression showed significant decrease at week 2 for PT cells and over time in nPT cells. Matrix gene ACAN was increased at 2 weeks in nPT and PT cells while MMP13 was significantly decreased in nPT cells at all time points and at week 4 for PT cells. GAG content was significantly increased
Refer to onsite annual meeting presentations and postmeeting proceedings for possible referenced figures and tables. Authors are responsible for accurately reporting disclosure and FDA device/drug status at time of abstract submission.
Proceedings of the 34th Annual Meeting of the North American Spine Society / The Spine Journal 19 (2019) S59−S100
STUDY DESIGN/SETTING: Multicenter review of single institutional case series. PATIENT SAMPLE: Patients under the age of 18 years who had been treated operatively for a thoracolumbar fracture between 2006 and 2016 were identified. Inclusion criteria included patients with preinjury computed tomography (CT) scans and magnetic resonance imaging (MRI) and who were less than 18 years of age. OUTCOME MEASURES: Classification through AOSpine Thoracolumbar Spine Injury Classification System METHODS: A group of nine POSNA (Pediatric Orthopaedic Society of North America) member surgeons were sent an electronic link containing educational videos and schematic papers describing the AOSpine Thoracolumbar Spine Injury Classification System. The link also contained MRI (magnetic resonance imaging) and CT (computed tomography) imaging of 25 pediatric patients with thoracolumbar spine injuries organized into cases to review and classify. The evaluators classified injuries into 3 primary categories: A, B, and C. Interobserver reliability was assessed for the initial reading across all 9 raters by Fleiss’s kappa coefficient (kF) along with 95% confidence intervals (CI). For A and B type injuries, subclassification was conducted including A0-A4 and B1-B2 subtypes. Interobserver reliability across subclasses was assessed using Krippendorff’s alpha (ak) along with bootstrapped 95% CIs. Imaging was reviewed a second time by all 9 evaluators approximately one month from the initial read. All patient imaging was blinded and randomized for each read independently. Intraobserver reproducibility was assessed for the primary classifications using Fleiss’s kappa and subclassification reproducibility was assessed by Krippendorff’s alpha (ak) along with 95% CIs. Interpretations for reliability estimates were based on Landis and Koch (1977): 0-0.2, slight; 0.2-0.4, fair; 0.4-0.6, moderate; 0.6-0.8, substantial; and >0.8, almost perfect agreement. RESULTS: Twenty-five cases were read by 9 raters for a total of 225 initial and 225 repeated evaluations. Interobserver reliability was almost perfect (kF = 0.82; CI = 0.77 - 0.87) across all 9 raters. Subclassification reliability was substantial (aK = 0.79; CI = 0.62 - 0.90). Intraobserver reproducibility was almost perfect (kF= 0.81; CI = 0.71 - 0.90) for both primary classifications and for subclassifications (ak = 0.81; CI = 0.73 - 0.86). CONCLUSIONS: The reliability for the AOSpine classification system was high amongst POSNA surgeons when applied to pediatric patients. Given a lack of a uniform classification in the pediatric population, the AOSpine Thoracolumbar Spine Injury Classification System has the potential to be used as the first universal spine fracture classification in children. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.181
165. Transverse pedicle angle is associated with pelvic incidence and increased in isthmic spondylolisthesis Atticus C. Coscia, BS1, Matthew R. Coscia, BA2, Erin C. Coscia, BA4, Michael B. Hostetter, MD3, Kevin O’Neill, MD2, Curtis Ramsey4, Michael F. Coscia, MD2; 1 Zionsville, IN, US; 2 Wake Forest University School of Medicine, Indianapolis, IN, USA; 3 CDI, Carmel, IN, US; 4 OrthoIndy, Indianapolis, IN, USA BACKGROUND CONTEXT: We examined lumbar transverse pedicle angle (TPA) in relation to pelvic incidence (PI) and made comparisons between patients with degenerative spondylolisthesis (DS), isthmic spondylolisthesis (IS), and controls. Higher PI was associated with increased TPA. TPA was similar between DS and controls but was significantly higher in IS compared to both DS and controls. This study is the first to demonstrate an association between TPA and PI, and the first to demonstrate a difference in transverse vertebral anatomy in IS. PURPOSE: We hypothesized that a larger TPA would be associated a higher PI, and that both PI and TPA would be higher in IS compared to controls and DS. STUDY DESIGN/SETTING: Retrospective radiographic review.
PATIENT SAMPLE: Retrospective radiograph analysis performed on 202 patients. Patients were greater than 18 years of age and either had a diagnosis of IS, DS or control. OUTCOME MEASURES: It has been postulated that a higher PI and associated increased lumbar lordosis resulting in increased stress across the pars is a potential causative factor in developing IS. Clinically, we observed an association between IS and increased TPA. The goal of this study was to investigate the potential relationship of TPA to PI, and compare these values between those with IS, DS, and controls. METHODS: A retrospective radiographic analysis was performed on patients greater than 18 years of age having a diagnosis of IS or DS, along with a control group, during the previous 10 years. PI and TPA measurements were made on lateral plane radiographs and CT scans of the lumbar spine. TPA was obtained by measuring the angle between a line perpendicular to the transverse isthmus and a line parallel to the vertebral midline, and was measured at L3-5. RESULTS: There were 202 patients (64 IS, 72 DS, 66 control) included in the study. Interrater reliability showed excellent agreement for PI and TPA (ICC > 0.80). Increasing PI predicted wider TPA across all three vertebral levels for the control group and for L5 in both IS and DS. TPA values for the DS group were not significantly different from controls at any level. However, TPA values (mean§std) for IS (L3: 14§4˚, L4: 17§4˚, L5: 26§ 5˚) were significantly higher than both the DS (L3: 12§3˚, L4: 14§4˚, L5: 22§5˚) and control (L3: 13§4˚, L4: 14§4˚, L5: 21§4˚) groups at all three lumbar vertebral levels measured. CONCLUSIONS: This study is the first to demonstrate an association between TPA and PI, and the first to demonstrate a difference in transverse vertebral anatomy in IS. A wider TPA along with increased PI may result in increased stress at the pars compared to having an increased PI alone, lending further insight into the development of spondylolysis. Further work is warranted to determine the effects of wider TPA and the pathophysiology of IS. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.182 166. Can C7 slope be used as a substitute for T1 slope? A radiographic analysis Ivan B. Ye1, Ray Tang, BA2, Zoe B. Cheung, MD3, Brian Cho, BS4, John Erdman, BA2, John T. Schwartz, BS5, Amir Taree, BA2, Andrew Warburton, BS2, Jun Kim, MD6, Samuel K. Cho, MD2; 1 Mount Sinai School of Medicine, New York, NY, US; 2 New York, NY, US; 3 Mount Sinai Hospital, New York, NY, US; 4 Icahn School of Medicine, New York, NY, US; 5 Icahn School of Medicine at Mount Sinai, New York, NY, US; 6 Mount Sinai Medical Center, New York, NY, US BACKGROUND CONTEXT: Sagittal imbalance in the cervical spine is a major cause of neck pain, headache, fatigue, and disability. While parameters such as C2-C7 lordosis and C2-C7 sagittal vertical axis have been extensively studied, they do not fully characterize cervical sagittal balance. T1 is an important new parameter of both cervical as well as global spinal sagittal balance. However, the T1 superior end plate can be difficult to visualize on standard lateral radiographs due to overlying anatomical structures. C7 slope has therefore been proposed as a potential substitute for T1 slope when the T1 superior end plate is not well visualized. PURPOSE: The objectives of this study were: (1) to assess the correlation between C7 slope and T1 slope on upright lateral cervical spine radiographs, and (2) to evaluate the inter-rater reliability of C7 slope. STUDY DESIGN/SETTING: This was a retrospective cohort study of cervical spine radiographs taken between December 2017 and June 2018 at a single institution. PATIENT SAMPLE: Only radiographs with visible C7 superior and inferior end plates, and T1 superior end plate were included. Radiographs with cervical instrumentation were excluded. OUTCOME MEASURES: Two independent observers measured upper C7 slope, lower C7 slope, and T1 slope.
Refer to onsite annual meeting presentations and postmeeting proceedings for possible referenced figures and tables. Authors are responsible for accurately reporting disclosure and FDA device/drug status at time of abstract submission.
Proceedings of the 34th Annual Meeting of the North American Spine Society / The Spine Journal 19 (2019) S59−S100 METHODS: The correlations between upper C7 slope and T1 slope, as well as between lower C7 slope and T1 slope were evaluated. Linear regression analyses were also performed. Inter-rater reliability of C7 slope as assessed. RESULTS: A total of 650 radiographs were reviewed. The superior end plate of C7, inferior end plate of C7, and superior end plate of T1 were visible in 72.9%, 50.2%, and 31.2% of these radiographs, respectively. After applying our exclusion criteria, 152 patients remained and were included in our analysis. The average age was 48.1 years, with 70.4% females. The average upper C7 slope, lower C7 slope, and T1 slope was 23.5˚§9.1˚, 22.9˚§9.0˚, and 27.5˚§8.7˚, respectively. There was a strong correlation between upper C7 slope and T1 slope (r=0.91, p<0.001), as well as between lower C7 slope and T1 slope (r=0.90, p<0.001). Linear regression analyses showed that T1 slope could be estimated from C7 slope based on the equation, T1 slope = 0.87 x C7 slope + 7, with an overall model fit of R2=0.8. There was strong inter-rater reliability for upper (ICC=0.95, p<0.001) and lower (ICC=0.96, p<0.001) C7 slope. CONCLUSIONS: Both the upper and lower C7 slope are strongly correlated with T1 slope and can be used as a substitute to estimate T1 slope when the superior end plate of T1 is not well visualized. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.183
167. Assessment of the efficacy of teriparatide (Forteo) in patients undergoing posterolateral lumbar spinal fusion: a double-blinded randomized pilot study Shane Burch, MD1, Kevin Taliaferro, MD2, Sigurd H. Berven, MD3, Vedat Deviren, MD1; 1 University of California San Francisco, San Francisco, CA, US; 2 UCSF Medical Center, San francisco, CA, US; 3 UCSF, Dept of Orthopaedic Surgery, San Francisco, CA, US BACKGROUND CONTEXT: Lumbar spinal fusion is an increasingly common procedure for treating degenerative diseases of the lumbar spine. Non-solid fusion, or pseudarthrosis, at one year is a common complication associated with poor clinical outcomes and need for revision surgery. The risk of pseudarthrosis depends on the number of levels fused, the fusion material, and patient risk factors (osteoporosis, smoking, diabetes, etc.). Although there are multiple options for bone graft and osteoinductive materials, all have their benefits, side-effects and cost. Teriparatide is an injectable recombinant analog of parathyroid hormone that has been well-studied in its treatment of osteoporosis. However, no clinical studies of its effect on spinal fusion in humans have been published to date. PURPOSE: To analyze the effect of teriparatide treatment on posterolateral spinal fusion in adults with degenerative diseases of the lumbar spine. STUDY DESIGN/SETTING: Multicenter prospective double-blinded randomized study. PATIENT SAMPLE: 60-90 year-olds with degenerative scoliosis, spondylolisthesis, or spondylosis at two medical centers undergoing instrumented posterolateral instrumented fusion >2levels. Use of BMP was excluded. OUTCOME MEASURES: Pseudoarthrosis, screw loosening, PJK by CT. VAS, ODI, and Eq5D. METHODS: Prospective randomized double-blind placebo-controlled pilot study performed at two large academic centers, UCSF and McGill University (Montreal). Included patients were aged 60-90 years with degenerative lumbar disease who were scheduled to undergo two-level or greater posterolateral lumbar spinal fusion. Patients were randomized in a 2:1 (Forteo:Placebo) manner. Patient were dosed 2 weeks pre-op and 10 weeks post-op. Patient derived outcomes were collected pre-op, 3, 6, 9, and 12 months. Fusions at 1 year were analyzed by helical CT. RESULTS: A total of 36 patients completed the study. 58.3% (n=21) received teriparatide. 42.8% (n=9) reported an adverse event. Fusion rate of all patients was 47.2% (n=17); the remaining 52.8% (n=19) demonstrated pseudoarthrosis at 1 year. Fourty-seven percent of patients
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receiving teriparatide had a pseudoarthrosis, while 60% of placebo had a pseudoarthrosis. VAS, ODI, and Eq5D improved in all groups but no significant difference was found between groups. CONCLUSIONS: Teriparatide appears to provide minimal benefit of avoiding pseudoarthroses in 60-90 year-olds undergoing thoracolumbar fusions. Teriparatide appears to have a fairly safe side effect profile. Further larger scale studies are warranted, possibly with the addition of BMP and/or bisphosphonates. FDA DEVICE/DRUG STATUS: Unavailable from authors at time of publication. https://doi.org/10.1016/j.spinee.2019.05.184
168. Non-viral transfection of human intervertebral disc cells with developmental factors induces reprogramming to a healthy anticatabolic/inflammatory phenotype with enhanced extracellular matrix accumulation Shirley N. Tang, BS1, Justin A. Richards2, Safdar N. Khan, MD3, Judith A. Hoyland4, Daniel Gallego-Perez, PhD1, Natalia Higuita-Castro, PhD1, Benjamin A. Walter, PhD1, Devina Purmessur, PhD (Walter)1; 1 The Ohio State University, Columbus, OH, USA; 2 Columbus, OH, USA; 3 The Ohio State University Wexner Medical Center, Columbus, OH, USA; 4 The University of Manchester, Manchester, United Kingdom BACKGROUND CONTEXT: Intervertebral disc (IVD) degeneration is a significant contributor to low back pain (LBP) and is characterized by a decrease in proteoglycan synthesis, increased catabolism, secretion of inflammatory factors and neurovascular invasion. Although viral gene therapies have been proposed for LBP treatment associated with IVD degeneration, there are concerns due to potential mutagenesis and unwarranted immune responses. To overcome these limitations, nonviral electroporation approaches have been developed. Transcription factor, Brachyury (T) is expressed in the developing notochord and associated with a healthy immature nucleus pulposus (NP) and thus it is a promising factor to reprogram degenerate IVD cells to halt degeneration and promote repair PURPOSE: To examine effects of Ttransfection on human NP cells exvivo. We hypothesize effective delivery of T can reprogram degenerate IVD cells into healthy cells with increased proteoglycan and decreased inflammatory, catabolic and pain factors. STUDY DESIGN/SETTING: 1) Cells isolated from patient and cadaveric human NP tissue. 2) Bulk electroporated with T3) 3D cultured over 4 weeks in agarose gels. PATIENT SAMPLE: N=5 samples from patients undergoing microdiscectomy (painful, 19-70yo) and N=5 cadaveric samples(nonpainful, 1958yo). IRB: 2015H0385 OUTCOME MEASURES: Gene expression (RT-qPCR) for healthy NP phenotypic markers, inflammatory/pain markers, matrix genes, and matrix cleaving enzymes, proteoglycan protein (GAG) (dimethylmethylene blue assay), cell viability (calcein/ethidium staining). METHODS: Cells were enzymatically isolated from NP tissue and expanded. Subsequently, nonpainful (nPT) andpainful (PT) NP cells were electroporated with a plasmids encoding for T, or an empty vector as a SHAM control. The transfected cells were then expanded in disc cell media and seeded in 3D agarose constructs. Outcome measures were examined at day 0, week 2 and week 4. Statistical Mann-Whitney Tests at a=0.05 were used. RESULTS: Cell viability remained high for all groups. Gene expression: healthy marker T was overexpressed and maintained for 4 weeks while KRT19 was significantly increased in nPT and PT cells compared to SHAM controls. Inflammatory cytokines IL-1b and IL6 decreased at 2 weeks for nPT cells and over time for PT cells. Pain marker NGF expression showed significant decrease at week 2 for PT cells and over time in nPT cells. Matrix gene ACAN was increased at 2 weeks in nPT and PT cells while MMP13 was significantly decreased in nPT cells at all time points and at week 4 for PT cells. GAG content was significantly increased
Refer to onsite annual meeting presentations and postmeeting proceedings for possible referenced figures and tables. Authors are responsible for accurately reporting disclosure and FDA device/drug status at time of abstract submission.