- Email: [email protected]
79. The regional effect of lumbar fusion surgery on volumetric bone mineral density measured by quantitative computed tomography in adjacent vertebrae: a longitudinal cohort study
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Proceedings of the 34th Annual Meeting of the North American Spine Society / The Spine Journal 19 (2019) S1−S58
77. Development of predictive models for 90-day and 1-year mortality in spinal metastatic disease Aditya V. Karhade, MD1, Christopher M. Bono, MD2, Marco Ferrone, MD3, Philip J. Saylor, MD4, Andrew J. Schoenfeld, MD3, John H. Shin, MD2, Mitchel Harris, MD, FACS2, Joseph H. Schwab, MD2; 1 Harvard Medical School, Boston, MA, US; 2 Massachusetts General Hospital, Boston, MA, US; 3 Brigham and Women’s Hospital, Boston, MA, US; 4 Boston, MA, US BACKGROUND CONTEXT: Increasing prevalence of metastatic disease has been accompanied by increasing rates of surgical intervention. Current tools have poor to fair predictive performance for intermediate (90-day) and long-term (one-year) mortality. PURPOSE: The purpose of this study was to develop predictive algorithms for spinal metastatic disease at these time points and to provide patient-specific explanations of the predictions generated by these algorithms. STUDY DESIGN/SETTING: Retrospective review was conducted at two large academic medical centers. PATIENT SAMPLE: Patients undergoing initial operative management for spinal metastatic disease between January 2000 and December 2016. OUTCOME MEASURES: Ninety-day and one-year overall survival. METHODS: Five models (penalized logistic regression, random forest, stochastic gradient boosting, neural network, and support vector machine) were developed to predict ninety-day and one-year mortality. RESULTS: Overall, 732 patients were identified with ninety-day and oneyear mortality rates of 181 (25.1%) and 385 (54.3%), respectively. The stochastic gradient boosting algorithm had the best performance for 90-day mortality and one-year mortality. On global variable importance assessment, albumin, primary tumor histology, and performance status were the three most important predictors of 90-day mortality. The final models were incorporated into an open access web application able to provide predictions as well as patient-specific explanations of the results generated by the algorithms. The application can be found at: https://sorg-apps.shinyapps. io/spinemetssurvival/ CONCLUSIONS: Preoperative estimation of 90-day and one-year mortality was achieved with assessment of more flexible modeling techniques such as machine learning. Integration of these models into applications and patient-centered explanations of predictions represent opportunities for incorporation into health care systems as decision tools in the future. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.090
78. Scoliosis surgery normalizes cardiac function in AIS patients Vishal Sarwahi, MD1, Aaron M. Atlas, BS2, Rachel Gecelter3, Jesse M. Galina, BS4, Sayyida S. Hasan, BS2, Melanie Gambassi, NP5, Kathleen Maguire, MD6, Yungtai Lo, PhD7, Terry D. Amaral, MD8; 1 North Shore LIJ Health System, New Hyde Park, NY, US; 2 Cohen Children’s Medical Center, New Hyde Park, NY, US; 3 Queens, NY, US; 4 New Hyde Path, US; 5 Northwell Health, Lake Success, NY, US; 6 Montefiore Medical Center, Bronx, NY, US; 7 Albert Einstein College of Medicine, Bronox, NY, US; 8 Northwell Health, Lake Success, NY, US BACKGROUND CONTEXT: Spinal deformity in asolescent idiopathic scoliosis (AIS) can increase right atrial and ventricular pressures secondary to restrictive lung disease. Pulmonary hypertension leading to cor pulmonale is the most feared outcome. However, mild pulmonary hypertension in AIS patients has been reported in the past. No study has examined these changes including the improvement of right heart function following scoliosis surgery. PURPOSE: To determine if scoliosis repair resolves cardiac function abnormalities. STUDY DESIGN/SETTING: Retrospective chart review.
PATIENT SAMPLE: A total of 363 patients: 184 AIS patients undergoing PSF, 179 healthty age-matched controls. OUTCOME MEASURES: Cobb angle, 2D-echo signs of structural heart disease, aortic root dimensions, tricuspid regurgitant jet velocity (TRV), PFTs, ABG, and patient demographics reviewed. Right ventricular systolic pressure (RVSP) was estimated using Bernoulli’s equation (4[TRV]2) and right atrial pressure. METHODS: Retrospective chart review. Group 1: 184 AIS patients, 1022 years of age, undergoing PSF from 2009-2013 at a single institution. Group 2 control patients: 179 healthy, age-matched adolescents. Cobb angle, 2D-echo signs of structural heart disease, aortic root dimensions, tricuspid regurgitant jet velocity (TRV), PFTs, ABG, and patient demographics reviewed. Right ventricular systolic pressure (RVSP) was estimated using Bernoulli’s equation (4[TRV]2) and right atrial pressure. RVSP ≥25 mmHg is a surrogate marker for pulmonary hypertension. All echocardiograms were read by board certified pediatric cardiologists. Group 3: 39 AIS patients from Group 1 with elevated preoperative TRV underwent corrective PSF. Logistic regression was used to assess for differences in TRV between groups. RESULTS: Mean preop RVSP was significantly elevated in AIS patients (25.7 vs 17.3; p<0.001) compared to controls. 39 (21%) group 1 patients had elevated preop TRV (≥ 2.8 m/s) vs no group 2 patients (p<0.001). In all Group 3 patients, the cardiac function normalized postop (mean TRV=2.92 vs 2.09; p<0.001). No association was found in Cobb angle, aortic root parameters, or PFTs. CONCLUSIONS: This study found that 21% of patients with AIS had elevated TRV while age-matched controls had no TRV abnormalities. Additionally, RVSP measurements demonstrated mild pulmonary hypertension in AIS patients. These abnormal values normalized postop, indicating the benefits of scoliosis surgery on cardiac function in AIS. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.091
79. The regional effect of lumbar fusion surgery on volumetric bone mineral density measured by quantitative computed tomography in adjacent vertebrae: a longitudinal cohort study Ichiro Okano, MD1, Conor M. Jones, BA2, Stephan Salzmann, MD1, Courtney Ortiz Miller, BA1, Jennifer Shue, MS1, John A. Carrino, MD, MPH1, Andrew A. Sama, MD1, Frank P. Cammisa, MD1, Federico P. Girardi, MD1, Alexander P. Hughes, MD1; 1 Hospital for Special Surgery, New York, NY, US; 2 New York, NY, US BACKGROUND CONTEXT: Previous studies reported that lumbar spine surgery has a negative effect on bone mineral density (BMD) in the lumbar spine. Dual X-ray absorptiometry (DXA) was generally used for following BMD change in these studie. However, DXA has several limitations for measuring BMD in the vertebrae with morphological changes and metal implants, which are often associated with lumbar spine surgery. Also, it is still unclear if this BMD change is caused by a local mechanical effect or a systemic physiological insult associated with the surgery. PURPOSE: To investigate the change of BMDs in multiple adjacent vertebrae utilizing quantitative computed tomography (QCT). STUDY DESIGN/SETTING: Retrospective cohort study at a single academic institution. PATIENT SAMPLE: Consecutive patients who underwent posterior lumbar spine surgery with instrumentation between 2014-2017 and had both preoperative and secondary postoperative computed tomography of the lumbar spine between 6 to 12 months. OUTCOME MEASURES: Regional trabecular vBMDs in the vertebral body by QCT. METHODS: Institutional ethics board approval was obtained for this study. Volumetric bone mineral density (vBMD) measurements by QCT were conducted in L1 to S1 vertebral trabecular bone. The change of vBMD in the vertebrae one or two-level above the upper instrumented
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) S1−S58 vertebra (UIV+1, UIV+2) and one level below the lower instrumented vertebra (LIV+1) were analyzed. Statistical analyses were conducted utilizing paired t-test, one-way/repeated-measures ANOVA, and Pearson’s correlation test. The statistical significance level was set at p<0.05. RESULTS: A total of 91 patients met our inclusion criteria. Mean age (&§ SD [range]) was 61.9 & 11.9; 55.6% of the patients were female. Median interval between the surgery and the secondary CT was 248 (180364) days. Volumetric BMD (&§ SD) in UIV+1 was 113.1 & § 32.6 mg/cm &>3 & preoperatively and 102.4 & § 32.2 mg/cm3 (percent change:-10.5 & § 12.6%) postoperatively (p <0.001). No correlation was observed between percent vBMD change in UIV+1 and interval between operation and postoperative CT (r=0.15, p=0.15). This trend of vBMD change was similar regardless of UIV level and number of fused level. The change of vBMDs in UIV+2 and LIV+1 appeared similar as UIV+1 (UIV +2: -11.9 & § 12.3%, p=0.19,LIV+1: -7.2 & § 20.7%, p=0.40). CONCLUSIONS: Posterior lumbar fusion surgery negatively affected the regional vBMDs measured by QCT in adjacent levels. BMDs in UIV+1, UIV+2, and LIV+1 were equally affected by the surgery. Our finding suggests that the postoperative decrease of regional BMDs in the lumbar spine dominantly occurs in the early postoperative phase (within 6 months) and a systemic effect has a greater role, rather than a regional mechanical one, in this postoperative BMD decline. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.092
80. Bariatric surgery prior to elective anterior cervical discectomy and fusion in obese patients is associated with a reduced risk of 90-day postoperative complications and readmissions Azeem T. Malik, MBBS1, Sheldon Retchin, MD2, Wendy Xu, PhD2, Scott S. Strassels, PhD2, Elizabeth Yu, MD1, Safdar N. Khan, MD1; 1 The Ohio State University Wexner Medical Center, Columbus, OH, US; 2 Columbus, OH, US BACKGROUND CONTEXT: Obese patients, particularly those with a body mass index (BMI) ≥35 kg/m2, pose a major challenge for a spine surgeon. Though obesity has previously been shown to be linked with adverse outcomes following elective spine surgical procedures, the impact of prior bariatric surgery on altering postoperative outcomes following elective anterior cervical discectomy and fusions (ACDFs) has not been explored. PURPOSE: To evaluate whether bariatric surgery prior to ACDF in obese Medicare patients reduces the risk of experiencing adverse postoperative outcomes. STUDY DESIGN/SETTING: Retrospective review of 100% Medicare Claims Database. PATIENT SAMPLE: The PearlDiver program was used to query the 2007-2013 100% Medicare Standard Analytical Files (SAF100) for patients undergoing an elective ACDF using International Classification of Diseases 9th Edition (ICD-9) procedure codes 81.02. Records were filtered to include only those patients who underwent a 1- to 2-level surgery using ICD-9 procedure code 81.62. Only those patients receiving an ACDF due to degenerative spine pathologies were included in the study. Finally, patients who did not have active enrollment up to 2 years prior and 1 year after the surgery were excluded. A total of 121,382 patients undergoing an elective 1- to 2-level ACDF were included in the final cohort. OUTCOME MEASURES: ICD-9 diagnosis codes were used to identify patients having at least moderate/Class II obesity (V85.35-V85.45, V85.4 and 278.01) within the last 2 years prior to an ACDF. Based on previously published literature, ICD-9 procedure codes for high gastric bypass (44.31), laparoscopic gastroenterostomy (44.38), other gastroenterostomy without gastrectomy (44.39), laparoscopic gastroplasty (44.68), laparoscopic gastric restrictive procedure (44.95-44.98), insertion of gastric bubble (44.93), other repair of stomach (44.69), open and other partial gastrectomy (43.89), isolation of intestinal segment (45.50-45.51),
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intestinal anastomosis (45.90, 45.91), partial gastrectomy with anastomosis to esophagus (43.5), duodenum (43.6) and jejunum (43.7) and other operations on stomach, unspecified (44.99) being coded on the same day as an obesity code were used to categorize patients receiving a bariatric surgical procedure.Only those patients receiving a bariatric surgery within 2 years prior to an ACDF were included. The 2-year mark was chosen as an arbitrary value. The study cohort was divided into two groups: (1) obese ACDF patients (BMI ≥35) receiving a bariatric surgery procedure within two years prior to an ACDF and (2) obese ACDF patients (BMI ≥35) without a known history of a bariatric surgical procedure within the last 2 years. Primary outcomes included 90-day complications (wound, pulmonary, cardiac, sepsis, renal, deep venous thrombosis, pain and dysphagia), 90-day readmissions, 90-day and 1-year revision cervical fusions. METHODS: Multivariate analyses were used to assess the impact of prior bariatric surgery on 90-day outcomes following ACDF, after adjusting for age, gender, region and Elixhauser Co-morbidity Index. RESULTS: A total of 6,128 patients with a BMI >35kg/m2 underwent ACDF, of which 411 ACDF patients underwent a bariatric surgical procedure within the 2 years prior to an ACDF. Multivariate analysis adjusting for age, gender, region and Elixhauser Co-morbidity Index (ECI), demonstrated that a history of prior bariatric surgery was associated with a significantly reduced rate of 90-day pulmonary complications (6.6% vs 12.7%, OR 0.53 [95% CI 0.34-0.78]; p=0.002), cardiac complications (15.3% vs 24.2%, OR 0.69 [95% CI 0.51-0.92]; p=0.012), sepsis (9.5% vs 15.1%, OR 0.69 [95% CI 0.48-0.96]; p=0.035), renal complications (2.9% vs 7.1%, OR 0.54 [95% CI 0.28-0.94]; p=0.044) and 90-day readmissions (3.9% vs 8.0%, OR 0.53 [95% CI 0.30-0.85]; p=0.015). Prior bariatric surgery had no statistically significant impact on the rates of wound complications (p=0.325), deep venous thrombosis (p=0.176), pain complications (p=0.606), dysphagia (p=0.171), 90-day revision (p=0.875) and 1-year revisions (p=0.313). CONCLUSIONS: Surgery-induced weight loss prior to an ACDF in obese patients is associated with reduced 90-day complication and readmission rates. Orthopedic and bariatric surgeons should counsel obese patients on the benefits of bariatric surgery following ACDFs. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.093
81. Nature of neurological deficits influences the treatment order preference for hip-spine syndrome Kirkham B. Wood, MD1, Stuart B. Goodman, MD, PhD2, Ning Liu, MD, MPH3, Paul F. Lachiewicz, MD4; 1 Stanford University School of Medicine Dept of Orthopedic Surgery, Redwood City, CA, US; 2 Stanford University School of Medicine, Redwood City, CA, US; 3 Stanford University, Redwood City, CA, US; 4 Duke University Department of Orthopaedic Surgery, Chapel Hill, NC, US BACKGROUND CONTEXT: With the aging of society, patients with concurrent degenerative lumbar disorders and hip osteoarthritis, also referred to as the "hip-spine syndrome," are frequently evaluated by both spine and arthroplasty surgeons. The decision-making can be straightforward in many but in others, the optimal treatment order—spine surgery or total hip arthroplasty (THA) first—remains unclear and complicated, especially when neurological deficits are involved. PURPOSE: To compare, in spine and arthroplasty surgeons respectively, the treatment order preference among four typical scenarios of hip-spine syndrome with different neurological symptoms. STUDY DESIGN/SETTING: Prospective survey at a professional society level. PATIENT SAMPLE: Eighty-eight experienced spine (37) and total hip arthroplasty (51) surgeons from the Scoliosis Research Society (SRS) and The Hip Society, respectively. OUTCOME MEASURES: Percentage of surgeons, in each specialty, choosing "spine first" in each scenario.
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) S1−S58
77. Development of predictive models for 90-day and 1-year mortality in spinal metastatic disease Aditya V. Karhade, MD1, Christopher M. Bono, MD2, Marco Ferrone, MD3, Philip J. Saylor, MD4, Andrew J. Schoenfeld, MD3, John H. Shin, MD2, Mitchel Harris, MD, FACS2, Joseph H. Schwab, MD2; 1 Harvard Medical School, Boston, MA, US; 2 Massachusetts General Hospital, Boston, MA, US; 3 Brigham and Women’s Hospital, Boston, MA, US; 4 Boston, MA, US BACKGROUND CONTEXT: Increasing prevalence of metastatic disease has been accompanied by increasing rates of surgical intervention. Current tools have poor to fair predictive performance for intermediate (90-day) and long-term (one-year) mortality. PURPOSE: The purpose of this study was to develop predictive algorithms for spinal metastatic disease at these time points and to provide patient-specific explanations of the predictions generated by these algorithms. STUDY DESIGN/SETTING: Retrospective review was conducted at two large academic medical centers. PATIENT SAMPLE: Patients undergoing initial operative management for spinal metastatic disease between January 2000 and December 2016. OUTCOME MEASURES: Ninety-day and one-year overall survival. METHODS: Five models (penalized logistic regression, random forest, stochastic gradient boosting, neural network, and support vector machine) were developed to predict ninety-day and one-year mortality. RESULTS: Overall, 732 patients were identified with ninety-day and oneyear mortality rates of 181 (25.1%) and 385 (54.3%), respectively. The stochastic gradient boosting algorithm had the best performance for 90-day mortality and one-year mortality. On global variable importance assessment, albumin, primary tumor histology, and performance status were the three most important predictors of 90-day mortality. The final models were incorporated into an open access web application able to provide predictions as well as patient-specific explanations of the results generated by the algorithms. The application can be found at: https://sorg-apps.shinyapps. io/spinemetssurvival/ CONCLUSIONS: Preoperative estimation of 90-day and one-year mortality was achieved with assessment of more flexible modeling techniques such as machine learning. Integration of these models into applications and patient-centered explanations of predictions represent opportunities for incorporation into health care systems as decision tools in the future. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.090
78. Scoliosis surgery normalizes cardiac function in AIS patients Vishal Sarwahi, MD1, Aaron M. Atlas, BS2, Rachel Gecelter3, Jesse M. Galina, BS4, Sayyida S. Hasan, BS2, Melanie Gambassi, NP5, Kathleen Maguire, MD6, Yungtai Lo, PhD7, Terry D. Amaral, MD8; 1 North Shore LIJ Health System, New Hyde Park, NY, US; 2 Cohen Children’s Medical Center, New Hyde Park, NY, US; 3 Queens, NY, US; 4 New Hyde Path, US; 5 Northwell Health, Lake Success, NY, US; 6 Montefiore Medical Center, Bronx, NY, US; 7 Albert Einstein College of Medicine, Bronox, NY, US; 8 Northwell Health, Lake Success, NY, US BACKGROUND CONTEXT: Spinal deformity in asolescent idiopathic scoliosis (AIS) can increase right atrial and ventricular pressures secondary to restrictive lung disease. Pulmonary hypertension leading to cor pulmonale is the most feared outcome. However, mild pulmonary hypertension in AIS patients has been reported in the past. No study has examined these changes including the improvement of right heart function following scoliosis surgery. PURPOSE: To determine if scoliosis repair resolves cardiac function abnormalities. STUDY DESIGN/SETTING: Retrospective chart review.
PATIENT SAMPLE: A total of 363 patients: 184 AIS patients undergoing PSF, 179 healthty age-matched controls. OUTCOME MEASURES: Cobb angle, 2D-echo signs of structural heart disease, aortic root dimensions, tricuspid regurgitant jet velocity (TRV), PFTs, ABG, and patient demographics reviewed. Right ventricular systolic pressure (RVSP) was estimated using Bernoulli’s equation (4[TRV]2) and right atrial pressure. METHODS: Retrospective chart review. Group 1: 184 AIS patients, 1022 years of age, undergoing PSF from 2009-2013 at a single institution. Group 2 control patients: 179 healthy, age-matched adolescents. Cobb angle, 2D-echo signs of structural heart disease, aortic root dimensions, tricuspid regurgitant jet velocity (TRV), PFTs, ABG, and patient demographics reviewed. Right ventricular systolic pressure (RVSP) was estimated using Bernoulli’s equation (4[TRV]2) and right atrial pressure. RVSP ≥25 mmHg is a surrogate marker for pulmonary hypertension. All echocardiograms were read by board certified pediatric cardiologists. Group 3: 39 AIS patients from Group 1 with elevated preoperative TRV underwent corrective PSF. Logistic regression was used to assess for differences in TRV between groups. RESULTS: Mean preop RVSP was significantly elevated in AIS patients (25.7 vs 17.3; p<0.001) compared to controls. 39 (21%) group 1 patients had elevated preop TRV (≥ 2.8 m/s) vs no group 2 patients (p<0.001). In all Group 3 patients, the cardiac function normalized postop (mean TRV=2.92 vs 2.09; p<0.001). No association was found in Cobb angle, aortic root parameters, or PFTs. CONCLUSIONS: This study found that 21% of patients with AIS had elevated TRV while age-matched controls had no TRV abnormalities. Additionally, RVSP measurements demonstrated mild pulmonary hypertension in AIS patients. These abnormal values normalized postop, indicating the benefits of scoliosis surgery on cardiac function in AIS. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.091
79. The regional effect of lumbar fusion surgery on volumetric bone mineral density measured by quantitative computed tomography in adjacent vertebrae: a longitudinal cohort study Ichiro Okano, MD1, Conor M. Jones, BA2, Stephan Salzmann, MD1, Courtney Ortiz Miller, BA1, Jennifer Shue, MS1, John A. Carrino, MD, MPH1, Andrew A. Sama, MD1, Frank P. Cammisa, MD1, Federico P. Girardi, MD1, Alexander P. Hughes, MD1; 1 Hospital for Special Surgery, New York, NY, US; 2 New York, NY, US BACKGROUND CONTEXT: Previous studies reported that lumbar spine surgery has a negative effect on bone mineral density (BMD) in the lumbar spine. Dual X-ray absorptiometry (DXA) was generally used for following BMD change in these studie. However, DXA has several limitations for measuring BMD in the vertebrae with morphological changes and metal implants, which are often associated with lumbar spine surgery. Also, it is still unclear if this BMD change is caused by a local mechanical effect or a systemic physiological insult associated with the surgery. PURPOSE: To investigate the change of BMDs in multiple adjacent vertebrae utilizing quantitative computed tomography (QCT). STUDY DESIGN/SETTING: Retrospective cohort study at a single academic institution. PATIENT SAMPLE: Consecutive patients who underwent posterior lumbar spine surgery with instrumentation between 2014-2017 and had both preoperative and secondary postoperative computed tomography of the lumbar spine between 6 to 12 months. OUTCOME MEASURES: Regional trabecular vBMDs in the vertebral body by QCT. METHODS: Institutional ethics board approval was obtained for this study. Volumetric bone mineral density (vBMD) measurements by QCT were conducted in L1 to S1 vertebral trabecular bone. The change of vBMD in the vertebrae one or two-level above the upper instrumented
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) S1−S58 vertebra (UIV+1, UIV+2) and one level below the lower instrumented vertebra (LIV+1) were analyzed. Statistical analyses were conducted utilizing paired t-test, one-way/repeated-measures ANOVA, and Pearson’s correlation test. The statistical significance level was set at p<0.05. RESULTS: A total of 91 patients met our inclusion criteria. Mean age (&§ SD [range]) was 61.9 & 11.9; 55.6% of the patients were female. Median interval between the surgery and the secondary CT was 248 (180364) days. Volumetric BMD (&§ SD) in UIV+1 was 113.1 & § 32.6 mg/cm &>3 & preoperatively and 102.4 & § 32.2 mg/cm3 (percent change:-10.5 & § 12.6%) postoperatively (p <0.001). No correlation was observed between percent vBMD change in UIV+1 and interval between operation and postoperative CT (r=0.15, p=0.15). This trend of vBMD change was similar regardless of UIV level and number of fused level. The change of vBMDs in UIV+2 and LIV+1 appeared similar as UIV+1 (UIV +2: -11.9 & § 12.3%, p=0.19,LIV+1: -7.2 & § 20.7%, p=0.40). CONCLUSIONS: Posterior lumbar fusion surgery negatively affected the regional vBMDs measured by QCT in adjacent levels. BMDs in UIV+1, UIV+2, and LIV+1 were equally affected by the surgery. Our finding suggests that the postoperative decrease of regional BMDs in the lumbar spine dominantly occurs in the early postoperative phase (within 6 months) and a systemic effect has a greater role, rather than a regional mechanical one, in this postoperative BMD decline. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.092
80. Bariatric surgery prior to elective anterior cervical discectomy and fusion in obese patients is associated with a reduced risk of 90-day postoperative complications and readmissions Azeem T. Malik, MBBS1, Sheldon Retchin, MD2, Wendy Xu, PhD2, Scott S. Strassels, PhD2, Elizabeth Yu, MD1, Safdar N. Khan, MD1; 1 The Ohio State University Wexner Medical Center, Columbus, OH, US; 2 Columbus, OH, US BACKGROUND CONTEXT: Obese patients, particularly those with a body mass index (BMI) ≥35 kg/m2, pose a major challenge for a spine surgeon. Though obesity has previously been shown to be linked with adverse outcomes following elective spine surgical procedures, the impact of prior bariatric surgery on altering postoperative outcomes following elective anterior cervical discectomy and fusions (ACDFs) has not been explored. PURPOSE: To evaluate whether bariatric surgery prior to ACDF in obese Medicare patients reduces the risk of experiencing adverse postoperative outcomes. STUDY DESIGN/SETTING: Retrospective review of 100% Medicare Claims Database. PATIENT SAMPLE: The PearlDiver program was used to query the 2007-2013 100% Medicare Standard Analytical Files (SAF100) for patients undergoing an elective ACDF using International Classification of Diseases 9th Edition (ICD-9) procedure codes 81.02. Records were filtered to include only those patients who underwent a 1- to 2-level surgery using ICD-9 procedure code 81.62. Only those patients receiving an ACDF due to degenerative spine pathologies were included in the study. Finally, patients who did not have active enrollment up to 2 years prior and 1 year after the surgery were excluded. A total of 121,382 patients undergoing an elective 1- to 2-level ACDF were included in the final cohort. OUTCOME MEASURES: ICD-9 diagnosis codes were used to identify patients having at least moderate/Class II obesity (V85.35-V85.45, V85.4 and 278.01) within the last 2 years prior to an ACDF. Based on previously published literature, ICD-9 procedure codes for high gastric bypass (44.31), laparoscopic gastroenterostomy (44.38), other gastroenterostomy without gastrectomy (44.39), laparoscopic gastroplasty (44.68), laparoscopic gastric restrictive procedure (44.95-44.98), insertion of gastric bubble (44.93), other repair of stomach (44.69), open and other partial gastrectomy (43.89), isolation of intestinal segment (45.50-45.51),
S39
intestinal anastomosis (45.90, 45.91), partial gastrectomy with anastomosis to esophagus (43.5), duodenum (43.6) and jejunum (43.7) and other operations on stomach, unspecified (44.99) being coded on the same day as an obesity code were used to categorize patients receiving a bariatric surgical procedure.Only those patients receiving a bariatric surgery within 2 years prior to an ACDF were included. The 2-year mark was chosen as an arbitrary value. The study cohort was divided into two groups: (1) obese ACDF patients (BMI ≥35) receiving a bariatric surgery procedure within two years prior to an ACDF and (2) obese ACDF patients (BMI ≥35) without a known history of a bariatric surgical procedure within the last 2 years. Primary outcomes included 90-day complications (wound, pulmonary, cardiac, sepsis, renal, deep venous thrombosis, pain and dysphagia), 90-day readmissions, 90-day and 1-year revision cervical fusions. METHODS: Multivariate analyses were used to assess the impact of prior bariatric surgery on 90-day outcomes following ACDF, after adjusting for age, gender, region and Elixhauser Co-morbidity Index. RESULTS: A total of 6,128 patients with a BMI >35kg/m2 underwent ACDF, of which 411 ACDF patients underwent a bariatric surgical procedure within the 2 years prior to an ACDF. Multivariate analysis adjusting for age, gender, region and Elixhauser Co-morbidity Index (ECI), demonstrated that a history of prior bariatric surgery was associated with a significantly reduced rate of 90-day pulmonary complications (6.6% vs 12.7%, OR 0.53 [95% CI 0.34-0.78]; p=0.002), cardiac complications (15.3% vs 24.2%, OR 0.69 [95% CI 0.51-0.92]; p=0.012), sepsis (9.5% vs 15.1%, OR 0.69 [95% CI 0.48-0.96]; p=0.035), renal complications (2.9% vs 7.1%, OR 0.54 [95% CI 0.28-0.94]; p=0.044) and 90-day readmissions (3.9% vs 8.0%, OR 0.53 [95% CI 0.30-0.85]; p=0.015). Prior bariatric surgery had no statistically significant impact on the rates of wound complications (p=0.325), deep venous thrombosis (p=0.176), pain complications (p=0.606), dysphagia (p=0.171), 90-day revision (p=0.875) and 1-year revisions (p=0.313). CONCLUSIONS: Surgery-induced weight loss prior to an ACDF in obese patients is associated with reduced 90-day complication and readmission rates. Orthopedic and bariatric surgeons should counsel obese patients on the benefits of bariatric surgery following ACDFs. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2019.05.093
81. Nature of neurological deficits influences the treatment order preference for hip-spine syndrome Kirkham B. Wood, MD1, Stuart B. Goodman, MD, PhD2, Ning Liu, MD, MPH3, Paul F. Lachiewicz, MD4; 1 Stanford University School of Medicine Dept of Orthopedic Surgery, Redwood City, CA, US; 2 Stanford University School of Medicine, Redwood City, CA, US; 3 Stanford University, Redwood City, CA, US; 4 Duke University Department of Orthopaedic Surgery, Chapel Hill, NC, US BACKGROUND CONTEXT: With the aging of society, patients with concurrent degenerative lumbar disorders and hip osteoarthritis, also referred to as the "hip-spine syndrome," are frequently evaluated by both spine and arthroplasty surgeons. The decision-making can be straightforward in many but in others, the optimal treatment order—spine surgery or total hip arthroplasty (THA) first—remains unclear and complicated, especially when neurological deficits are involved. PURPOSE: To compare, in spine and arthroplasty surgeons respectively, the treatment order preference among four typical scenarios of hip-spine syndrome with different neurological symptoms. STUDY DESIGN/SETTING: Prospective survey at a professional society level. PATIENT SAMPLE: Eighty-eight experienced spine (37) and total hip arthroplasty (51) surgeons from the Scoliosis Research Society (SRS) and The Hip Society, respectively. OUTCOME MEASURES: Percentage of surgeons, in each specialty, choosing "spine first" in each scenario.
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.