- Email: [email protected]
The Substantial Clinical Benefit Threshold for SRS-22R Domains after Surgical Treatment of Adult Spinal Deformity
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Proceedings of the NASS 30th Annual Meeting / The Spine Journal 15 (2015) 87S–267S
RESULTS: Combined professional and facility costs for a single level ACDF had a national mean of $13,899 (range $14,044). Total costs for a single-level PLF had a mean of $25,858 (range $17,437). Total costs for a primary TKA had a national mean of $13,039 (range $8,839). The cost increased to an average of $22,138 (range $13,138) for TKA with MCC. Analysis of geographic trends showed statistically significant differences in total costs of PLF, TKA, and TKA with MCC between geographic regions (p!0.01 for all). CONCLUSIONS: Three of the four procedures (PLF, TKA, TKA with MCC) had statistically significant variation in cost associated with geographic regions. The Midwest consistently provided the lowest cost for all three procedures. States in the Northeast, on average, had the highest costs (PLF $28,348, TKA $14,376, TKA with MCC $24,622). Similar geographic trends in the cost of spinal fusions and TKAs suggest that these trends may not be limited to just spine-related procedures. This study clearly defines the costs associated with ACDF and PLF including the variation seen across the United States. The analyses found that the costs of PLF and TKA were associated with geographic region. Surgical costs were also found to correlate with the cost of living, but were not associated with the population of the state. This data sheds light on the cost of common surgeries throughout the United States and will allow further progress towards the development of cost effective, value driven care. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. http://dx.doi.org/10.1016/j.spinee.2015.07.297
P62. Lumbar Surgery in the Elderly Provides Significant Health Benefit and Value in the US Healthcare System: Patient-Reported Outcomes in 4,370 Patients from the N2QOD Registry Scott L. Parker, MD1, Matthew J. McGirt, MD2, Alan S. Hilibrand, MD3, Clinton J. Devin, MD4, Steven D. Glassman, MD5, Anthony Asher, MD, FACS6; 1Vanderbilt University, Nashville, TN, US; 2Carolina Neurosurgery & Spine Associates, Charlotte, NC, US; 3Rothman Institute, Philadelphia, PA, US; 4Vanderbilt University Medical Center, Nashville, TN, US; 5 Norton Leatherman Spine Center, Louisville, KY, US; 6Carolina Neurosurgery & Spine Association, Charlotte, NC, US BACKGROUND CONTEXT: In the value-based health care reform era, all stakeholders are demanding objective patient-centered evidence to support continuation of high cost treatment options. Degenerative spine conditions and their surgical treatments are among the most prevalent and costly in the US health care system. Given the rapidly growing elderly population, the unsustainable cost of healthcare, and the perceived risk and questioned value of spine surgery in the elderly, the demand for proven health benefit with spine surgery in this prevalent and costly population is at its highest. PURPOSE: To understand value (cost/qaly gained) of lumbar surgery in the elderly. STUDY DESIGN/SETTING: Nationwide prospective longitudinal patient registry. PATIENT SAMPLE: All lumbar surgery cases enrolled into N2QOD were queried in order to compare the elderly surgical population ($70 years old) and associated outcomes with patients !70 years of age. OUTCOME MEASURES: Visual Analog Scale (VAS) for pain, Oswestry Disability Index (ODI), EuroQol-5D (EQ-5D), surgical complications, 90-day hospital readmission. METHODS: The N2QOD registry enrolls spine surgery patients from 52 hospitals across 26 states via representative sampling and prospectively collects measures of surgical safety and patient-reported outcomes for one year after surgery. All lumbar surgery cases enrolled into N2QOD were queried in order to compare the elderly surgical population ($70 years old) and associated outcomes with patients !70 years of age. RESULTS: 4,370 lumbar spine surgeries were enrolled in N2QOD with one year follow-up. 1,020 (23%) were elderly. Elderly patients had an
increased incidence of heart disease, osteoporosis, high risk anesthesia grade (ASA 3/4), O3 level surgery, ambulation assist device use, unemployment, female gender, Caucasian race and stenosis as a diagnosis. Elderly had a lower BMI and incidence of anxiety/depression, liability/ worker’s compensation claims, and disc herniation as diagnosis. Utilization of fusion and symptom type and severity were similar between elderly vs nonelderly. Length of hospital stay (2 [1-4] vs 1 [0-3], p!0.001; median [IQR]) and need for postdischarge inpatient rehab/nursing facility (24.5% vs 8.2%, p!0.001) was greater for elderly. Incidences of surgical complication and 90-day hospital readmission were equally low (2%). For the few employed elderly (9.7%), incidence of return to work was decreased (62% vs 78%, p!0.001) and duration of missed work prolonged by 1 week (p! 0.001). Significant and equivalent improvements in one-year pain, disability and quality of life were reported by both elderly and nonelderly patients overall and for each unique spine diagnosis (disc herniation, spondylolisthesis, stenosis and adjacent segment disease). CONCLUSIONS: In patients of all ages, lumbar spine surgery resulted in significant improvement in pain, disability, quality of life and occupational productivity. Despite a longer length of hospital stay and greater need for post-discharge rehabilitation or skilled nursing care, elderly patients over 70 years of age experienced equivalent and significant health benefit in all measured health domains without an increased rate of surgical complication or hospital readmission. Elective lumbar spine surgery in the elderly provides significant gains in all domains of health status, justifying its continued utilization in this growing population. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. http://dx.doi.org/10.1016/j.spinee.2015.07.298
P63. The Substantial Clinical Benefit Threshold for SRS-22R Domains after Surgical Treatment of Adult Spinal Deformity Leah Y. Carreon, MD, MSc1, Charles H. Crawford, III, MD1, Steven D. Glassman, MD1, Keith H. Bridwell, MD2; 1Norton Leatherman Spine Center, Louisville, KY, US; 2Washington University in St. Louis School of Medicine, Saint Louis, MO, US BACKGROUND CONTEXT: The Scoliosis Research Society-22R (SRS-22R) has been shown to be reliable, valid and responsive to change in patients undergoing surgery for adult spinal deformity. Although the Minimum Clinically Important Difference (MCID) is commonly used to quantify a threshold of improvement, it could be considered a floor value rather than a goal. For this reason, the concept of Substantial Clinical Benefit (SCB) was introduced. Establishing the SCB will help clinicians and researchers identify changes in the domain scores that are important to the individual patient. PURPOSE: To establish the SCB threshold values for the SRS-22R domains in patients undergoing surgical correction of adult spinal deformity. STUDY DESIGN/SETTING: Secondary analysis of a longitudinal cohort. PATIENT SAMPLE: Patients enrolled in a prospective database of adult spinal deformity undergoing surgical treatment form the basis of this study. Patients who completed the English version of the SRS-22R preoperatively and the SRS-30 at one year postoperatively were identified. OUTCOME MEASURES: The SRS-22R and SRS-30. The SRS-30 consists of the 22 items from the SRS-22R with an additional 8 questions. Item 23 is a global self-image rating while items 24 to 30 are questions that pertain to a patient’s perceptions regarding pain, appearance and activity after surgery. METHODS: One-year postoperative answers to the last 8 questions of the SRS-30 were used as anchors to determine the SCB for the Appearance and Activity domains. Anchors were not available for the Mental domain. Paired sample t-tests were used to compare preoperative and one-year postoperative domain scores. One-way ANOVA was used to compare change in domain scores between groups classified according to responses
Refer to onsite Annual Meeting presentations and postmeeting proceedings for possible referenced figures and tables. Authors are responsible for accurately reporting disclosures and FDA device/drug status at time of abstract submission.
Proceedings of the NASS 30th Annual Meeting / The Spine Journal 15 (2015) 87S–267S to the anchor question. SCB values for the SRS-22R domains were determined using Receiver-Operating-Characteristic Curve Analysis with the Anchor scores. RESULTS: The sample population consisted of 1,321 patients who underwent surgical treatment for adult spinal deformity. 83% were females and 10% reported smoking. Mean age was 53 6 16 years. Mean BMI was 26.3 6 5.8 kg/m2. There was a statistically significant difference in domain scores among the responses to the anchors (p!0.001). Mean preop SRS22R Appearance domain score was 2.50 6 0.73 which improved to 3.62 6 0.84 at one year postop. Mean preop SRS-22R Activity domain score was 2.96 6 0.59 which improved to 3.33 6 0.80 at one year postop. Mean preop SRS-22R Pain domain score was 2.73 6 0.92 which improved to 3.60 6 0.93 at one year postop. Mean preop SRS-22R Subscore was 2.56 6 0.66 which improved to 3.11 6 0.80 at one year postop. According to the ROC analysis, SCB was 1.60 (AUC50.798) for the SRS-22R Appearance domain, 0.87 (AUC50.742) for the SRS-22R Activity domain, 0.69 (AUC50.750) for the SRS-22R Subscore AND 0.94 (AUC50.790) for the SRS-22R Total score. CONCLUSIONS: The results of the current study in an adult spinal deformity population undergoing surgical treatment show SRS22R SCB values of 1.60 for Appearance, 0.87 for Activity, 0.69 for Subscore and 0.94 for Total score. These SCB thresholds that can be used to quantify the clinical significance of health status change in the surgical management of adult spinal deformity. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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RESULTS: The average increase in segmental lordosis at the instrumented level was 2.6 -5.9 with a single level construct, 9.7 -17.9 with a two level construct, and 13.5 -22.2 with a three level construct. Increasing cage lordosis lead to global increases in cervical lordosis. The average increase in cervical lordosis was 5.9 -8.0 with a single-level construct, 10.6 -15.8 with a two-level construct, and 11.6 -20.4 with a three-level construct. As implanted lordosis increased, the suboccipital levels compensated by decreasing in lordosis to maintain horizontal gaze. The average decrease in Occ-C2 lordosis was 6.7 -8.9 with a single-level construct, 10.9 -14.2 with a two-level construct and 11.0 -19.4 with a three-level construct. An increase in cage lordosis corresponded with larger changes in SVA. The change in SVA was 7.8-9.4 mm for the single-level construct, 12.017.5 mm for the two-level construct and 11.5-17.7 mm for the three-level construct. The two-level constructs resulted in larger changes in SVA than their three-level counterparts with similar amounts of cage lordosis, eg, two 15 cages versus three 10 cages. CONCLUSIONS: Adding more implant lordosis led to larger changes in lordosis and SVA, and larger reciprocal changes. Reciprocal compensation was observed in the suboccipital and subaxial cervical spine, with the OccC2 segment undergoing the largest compensation. When comparing twoand three-level constructs with similar amounts of implanted lordosis, the two-level constructs created similar increases in cervical lordosis and subsequent Occ-C2 compensation. The two-level constructs also created larger changes in SVA. Implants with SL may allow for increased capabilities in correcting cervical sagittal plane deformity. FDA DEVICE/DRUG STATUS: CoRoent Small ACR Interbody (Not approved for this indication).
http://dx.doi.org/10.1016/j.spinee.2015.07.299 http://dx.doi.org/10.1016/j.spinee.2015.07.300 P64. An In Vitro Evaluation of Sagittal Alignment in the Cervical Spine after Insertion of Supraphysiologic Lordotic Implants Jeffrey E. Harris, MS1, Donald J. Blaskiewicz, MD2, Patrick P. Han, MD3, Alexander W. Turner, PhD1, Gregory M. Mundis, Jr., MD4; 1NuVasive, San Diego, CA, US; 2Neurosurgical Medical Clinic, San Diego, CA, US; 3St. John Neuroscience Institute, Tulsa, OK, US; 4Scripps Clinic Medical Group Department of Orthopedics, La Jolla, CA, US BACKGROUND CONTEXT: Cervical spine malalignment can develop as a consequence of degenerative disc disease or following spinal surgery. When normal sagittal alignment of the spine is disrupted, further degeneration may occur adjacent to the deformity. Circumferential fusion procedures are commonly performed to restore lordosis and sagittal alignment of the cervical spine. Due to the morbidity of these procedures, patients may benefit from single approach surgery capable of providing similar correction. The use of implants with supraphysiologic lordosis (SL) has been proposed as a single approach alternative to circumferential procedures. The effectiveness of SL implants on restoring lordosis and sagittal alignment, as well as its impact on the adjacent segments, has not been studied. PURPOSE: The purpose of this study was to evaluate the change in lordosis, sagittal alignment and the subsequent reciprocal changes of the cervical spine after implantation of supraphysiologic lordotic cages of varying angles at 1, 2 and 3 levels. STUDY DESIGN/SETTING: In vitro, cadaveric, biomechanical. METHODS: Eight human cadaveric occiput-T1 segments were dissected and potted at the cephalad and caudal levels. Each spine was placed in a testing apparatus and constrained with the T1 tilt fixed at 23 , which assumes an asymptomatic thoraco-lumbar spine. The occiput was free to translate in the cranial-caudal and anterior-posterior planes, and restricted from rotation to ensure horizontal gaze regardless of the simulated surgical correction. SL implants with angles of 7 , 10 , 15 and 20 were implanted in stages and different combinations, starting with single-level constructs (C5-6), followed by two (C5-7), and three-level (C4-7) constructs. Radiographs were taken intact and after each stage of implantation. Measurements included segmental lordosis at each level between C2-7, Occ-C2 angle and SVA.
P65. Surgical Treatment of Scoliosis in Marfan Syndrome: Anterior Combined with Posterior Approach versus Posterior-Only Approach Xiao Han, II1, Jun Qiao, MD2, Zezhang Zhu, PhD3, Feng Zhu, MD3, Bin Wang, MD3, Bangping Qian, MD3, Yang Yu, MD3, Yong Qiu, MD3; 1 Nanjing, China; 2Nanjing Gulou Hospital, Nanjing, Jiangsu, China; 3The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, China BACKGROUND CONTEXT: Scoliosis is the most commonly seen skeletal disorder associated with Marfan syndrome. Surgical treatment is applied to most of these patients. PURPOSE: To compare surgical outcomes of scoliosis associated with Marfan syndrome between anterior combined with posterior approach versus posterior-only approach. STUDY DESIGN/SETTING: A retrospective review was performed on the records of patients with Marfan syndrome from one single institution from 1998 to 2012. PATIENT SAMPLE: Inclusion criteria were patients who were 10 to 20 years of age, had a diagnosis of Marfan syndrome by the Ghent nosology, had scoliosis and had undergone spinal fusion, and had at least 2 years of postoperative follow-up. METHODS: The medical records of all patients were reviewed for age at the time of surgery, surgical procedures performed, instrumentation type, estimated blood loss (EBL) during surgery, operation time and complications related to surgery. Health-related quality-of-life measures (obtained with the SRS-22 Questionnaire before operation and at the last clinical follow-up) were also recorded. Patients were analyzed as two different groups, Group 1 and Group 2, according to the different approaches employed. Patients receiving combined anterior and posterior surgery were assigned to Group 1 and those who received posterioronly to Group 2. RESULTS: Group 1 consisted of 30 patients (42 males, 54 females) with a mean age at surgery of 16.8 years (range: 10 - 20). Complications in Group 1 included 2 cases of instrumentation loosening with 1 removed, 1 case of instrumentation breakage and 1 case of chylothorax and hemothorax
Refer to onsite Annual Meeting presentations and postmeeting proceedings for possible referenced figures and tables. Authors are responsible for accurately reporting disclosures and FDA device/drug status at time of abstract submission.
Proceedings of the NASS 30th Annual Meeting / The Spine Journal 15 (2015) 87S–267S
RESULTS: Combined professional and facility costs for a single level ACDF had a national mean of $13,899 (range $14,044). Total costs for a single-level PLF had a mean of $25,858 (range $17,437). Total costs for a primary TKA had a national mean of $13,039 (range $8,839). The cost increased to an average of $22,138 (range $13,138) for TKA with MCC. Analysis of geographic trends showed statistically significant differences in total costs of PLF, TKA, and TKA with MCC between geographic regions (p!0.01 for all). CONCLUSIONS: Three of the four procedures (PLF, TKA, TKA with MCC) had statistically significant variation in cost associated with geographic regions. The Midwest consistently provided the lowest cost for all three procedures. States in the Northeast, on average, had the highest costs (PLF $28,348, TKA $14,376, TKA with MCC $24,622). Similar geographic trends in the cost of spinal fusions and TKAs suggest that these trends may not be limited to just spine-related procedures. This study clearly defines the costs associated with ACDF and PLF including the variation seen across the United States. The analyses found that the costs of PLF and TKA were associated with geographic region. Surgical costs were also found to correlate with the cost of living, but were not associated with the population of the state. This data sheds light on the cost of common surgeries throughout the United States and will allow further progress towards the development of cost effective, value driven care. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. http://dx.doi.org/10.1016/j.spinee.2015.07.297
P62. Lumbar Surgery in the Elderly Provides Significant Health Benefit and Value in the US Healthcare System: Patient-Reported Outcomes in 4,370 Patients from the N2QOD Registry Scott L. Parker, MD1, Matthew J. McGirt, MD2, Alan S. Hilibrand, MD3, Clinton J. Devin, MD4, Steven D. Glassman, MD5, Anthony Asher, MD, FACS6; 1Vanderbilt University, Nashville, TN, US; 2Carolina Neurosurgery & Spine Associates, Charlotte, NC, US; 3Rothman Institute, Philadelphia, PA, US; 4Vanderbilt University Medical Center, Nashville, TN, US; 5 Norton Leatherman Spine Center, Louisville, KY, US; 6Carolina Neurosurgery & Spine Association, Charlotte, NC, US BACKGROUND CONTEXT: In the value-based health care reform era, all stakeholders are demanding objective patient-centered evidence to support continuation of high cost treatment options. Degenerative spine conditions and their surgical treatments are among the most prevalent and costly in the US health care system. Given the rapidly growing elderly population, the unsustainable cost of healthcare, and the perceived risk and questioned value of spine surgery in the elderly, the demand for proven health benefit with spine surgery in this prevalent and costly population is at its highest. PURPOSE: To understand value (cost/qaly gained) of lumbar surgery in the elderly. STUDY DESIGN/SETTING: Nationwide prospective longitudinal patient registry. PATIENT SAMPLE: All lumbar surgery cases enrolled into N2QOD were queried in order to compare the elderly surgical population ($70 years old) and associated outcomes with patients !70 years of age. OUTCOME MEASURES: Visual Analog Scale (VAS) for pain, Oswestry Disability Index (ODI), EuroQol-5D (EQ-5D), surgical complications, 90-day hospital readmission. METHODS: The N2QOD registry enrolls spine surgery patients from 52 hospitals across 26 states via representative sampling and prospectively collects measures of surgical safety and patient-reported outcomes for one year after surgery. All lumbar surgery cases enrolled into N2QOD were queried in order to compare the elderly surgical population ($70 years old) and associated outcomes with patients !70 years of age. RESULTS: 4,370 lumbar spine surgeries were enrolled in N2QOD with one year follow-up. 1,020 (23%) were elderly. Elderly patients had an
increased incidence of heart disease, osteoporosis, high risk anesthesia grade (ASA 3/4), O3 level surgery, ambulation assist device use, unemployment, female gender, Caucasian race and stenosis as a diagnosis. Elderly had a lower BMI and incidence of anxiety/depression, liability/ worker’s compensation claims, and disc herniation as diagnosis. Utilization of fusion and symptom type and severity were similar between elderly vs nonelderly. Length of hospital stay (2 [1-4] vs 1 [0-3], p!0.001; median [IQR]) and need for postdischarge inpatient rehab/nursing facility (24.5% vs 8.2%, p!0.001) was greater for elderly. Incidences of surgical complication and 90-day hospital readmission were equally low (2%). For the few employed elderly (9.7%), incidence of return to work was decreased (62% vs 78%, p!0.001) and duration of missed work prolonged by 1 week (p! 0.001). Significant and equivalent improvements in one-year pain, disability and quality of life were reported by both elderly and nonelderly patients overall and for each unique spine diagnosis (disc herniation, spondylolisthesis, stenosis and adjacent segment disease). CONCLUSIONS: In patients of all ages, lumbar spine surgery resulted in significant improvement in pain, disability, quality of life and occupational productivity. Despite a longer length of hospital stay and greater need for post-discharge rehabilitation or skilled nursing care, elderly patients over 70 years of age experienced equivalent and significant health benefit in all measured health domains without an increased rate of surgical complication or hospital readmission. Elective lumbar spine surgery in the elderly provides significant gains in all domains of health status, justifying its continued utilization in this growing population. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. http://dx.doi.org/10.1016/j.spinee.2015.07.298
P63. The Substantial Clinical Benefit Threshold for SRS-22R Domains after Surgical Treatment of Adult Spinal Deformity Leah Y. Carreon, MD, MSc1, Charles H. Crawford, III, MD1, Steven D. Glassman, MD1, Keith H. Bridwell, MD2; 1Norton Leatherman Spine Center, Louisville, KY, US; 2Washington University in St. Louis School of Medicine, Saint Louis, MO, US BACKGROUND CONTEXT: The Scoliosis Research Society-22R (SRS-22R) has been shown to be reliable, valid and responsive to change in patients undergoing surgery for adult spinal deformity. Although the Minimum Clinically Important Difference (MCID) is commonly used to quantify a threshold of improvement, it could be considered a floor value rather than a goal. For this reason, the concept of Substantial Clinical Benefit (SCB) was introduced. Establishing the SCB will help clinicians and researchers identify changes in the domain scores that are important to the individual patient. PURPOSE: To establish the SCB threshold values for the SRS-22R domains in patients undergoing surgical correction of adult spinal deformity. STUDY DESIGN/SETTING: Secondary analysis of a longitudinal cohort. PATIENT SAMPLE: Patients enrolled in a prospective database of adult spinal deformity undergoing surgical treatment form the basis of this study. Patients who completed the English version of the SRS-22R preoperatively and the SRS-30 at one year postoperatively were identified. OUTCOME MEASURES: The SRS-22R and SRS-30. The SRS-30 consists of the 22 items from the SRS-22R with an additional 8 questions. Item 23 is a global self-image rating while items 24 to 30 are questions that pertain to a patient’s perceptions regarding pain, appearance and activity after surgery. METHODS: One-year postoperative answers to the last 8 questions of the SRS-30 were used as anchors to determine the SCB for the Appearance and Activity domains. Anchors were not available for the Mental domain. Paired sample t-tests were used to compare preoperative and one-year postoperative domain scores. One-way ANOVA was used to compare change in domain scores between groups classified according to responses
Refer to onsite Annual Meeting presentations and postmeeting proceedings for possible referenced figures and tables. Authors are responsible for accurately reporting disclosures and FDA device/drug status at time of abstract submission.
Proceedings of the NASS 30th Annual Meeting / The Spine Journal 15 (2015) 87S–267S to the anchor question. SCB values for the SRS-22R domains were determined using Receiver-Operating-Characteristic Curve Analysis with the Anchor scores. RESULTS: The sample population consisted of 1,321 patients who underwent surgical treatment for adult spinal deformity. 83% were females and 10% reported smoking. Mean age was 53 6 16 years. Mean BMI was 26.3 6 5.8 kg/m2. There was a statistically significant difference in domain scores among the responses to the anchors (p!0.001). Mean preop SRS22R Appearance domain score was 2.50 6 0.73 which improved to 3.62 6 0.84 at one year postop. Mean preop SRS-22R Activity domain score was 2.96 6 0.59 which improved to 3.33 6 0.80 at one year postop. Mean preop SRS-22R Pain domain score was 2.73 6 0.92 which improved to 3.60 6 0.93 at one year postop. Mean preop SRS-22R Subscore was 2.56 6 0.66 which improved to 3.11 6 0.80 at one year postop. According to the ROC analysis, SCB was 1.60 (AUC50.798) for the SRS-22R Appearance domain, 0.87 (AUC50.742) for the SRS-22R Activity domain, 0.69 (AUC50.750) for the SRS-22R Subscore AND 0.94 (AUC50.790) for the SRS-22R Total score. CONCLUSIONS: The results of the current study in an adult spinal deformity population undergoing surgical treatment show SRS22R SCB values of 1.60 for Appearance, 0.87 for Activity, 0.69 for Subscore and 0.94 for Total score. These SCB thresholds that can be used to quantify the clinical significance of health status change in the surgical management of adult spinal deformity. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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RESULTS: The average increase in segmental lordosis at the instrumented level was 2.6 -5.9 with a single level construct, 9.7 -17.9 with a two level construct, and 13.5 -22.2 with a three level construct. Increasing cage lordosis lead to global increases in cervical lordosis. The average increase in cervical lordosis was 5.9 -8.0 with a single-level construct, 10.6 -15.8 with a two-level construct, and 11.6 -20.4 with a three-level construct. As implanted lordosis increased, the suboccipital levels compensated by decreasing in lordosis to maintain horizontal gaze. The average decrease in Occ-C2 lordosis was 6.7 -8.9 with a single-level construct, 10.9 -14.2 with a two-level construct and 11.0 -19.4 with a three-level construct. An increase in cage lordosis corresponded with larger changes in SVA. The change in SVA was 7.8-9.4 mm for the single-level construct, 12.017.5 mm for the two-level construct and 11.5-17.7 mm for the three-level construct. The two-level constructs resulted in larger changes in SVA than their three-level counterparts with similar amounts of cage lordosis, eg, two 15 cages versus three 10 cages. CONCLUSIONS: Adding more implant lordosis led to larger changes in lordosis and SVA, and larger reciprocal changes. Reciprocal compensation was observed in the suboccipital and subaxial cervical spine, with the OccC2 segment undergoing the largest compensation. When comparing twoand three-level constructs with similar amounts of implanted lordosis, the two-level constructs created similar increases in cervical lordosis and subsequent Occ-C2 compensation. The two-level constructs also created larger changes in SVA. Implants with SL may allow for increased capabilities in correcting cervical sagittal plane deformity. FDA DEVICE/DRUG STATUS: CoRoent Small ACR Interbody (Not approved for this indication).
http://dx.doi.org/10.1016/j.spinee.2015.07.299 http://dx.doi.org/10.1016/j.spinee.2015.07.300 P64. An In Vitro Evaluation of Sagittal Alignment in the Cervical Spine after Insertion of Supraphysiologic Lordotic Implants Jeffrey E. Harris, MS1, Donald J. Blaskiewicz, MD2, Patrick P. Han, MD3, Alexander W. Turner, PhD1, Gregory M. Mundis, Jr., MD4; 1NuVasive, San Diego, CA, US; 2Neurosurgical Medical Clinic, San Diego, CA, US; 3St. John Neuroscience Institute, Tulsa, OK, US; 4Scripps Clinic Medical Group Department of Orthopedics, La Jolla, CA, US BACKGROUND CONTEXT: Cervical spine malalignment can develop as a consequence of degenerative disc disease or following spinal surgery. When normal sagittal alignment of the spine is disrupted, further degeneration may occur adjacent to the deformity. Circumferential fusion procedures are commonly performed to restore lordosis and sagittal alignment of the cervical spine. Due to the morbidity of these procedures, patients may benefit from single approach surgery capable of providing similar correction. The use of implants with supraphysiologic lordosis (SL) has been proposed as a single approach alternative to circumferential procedures. The effectiveness of SL implants on restoring lordosis and sagittal alignment, as well as its impact on the adjacent segments, has not been studied. PURPOSE: The purpose of this study was to evaluate the change in lordosis, sagittal alignment and the subsequent reciprocal changes of the cervical spine after implantation of supraphysiologic lordotic cages of varying angles at 1, 2 and 3 levels. STUDY DESIGN/SETTING: In vitro, cadaveric, biomechanical. METHODS: Eight human cadaveric occiput-T1 segments were dissected and potted at the cephalad and caudal levels. Each spine was placed in a testing apparatus and constrained with the T1 tilt fixed at 23 , which assumes an asymptomatic thoraco-lumbar spine. The occiput was free to translate in the cranial-caudal and anterior-posterior planes, and restricted from rotation to ensure horizontal gaze regardless of the simulated surgical correction. SL implants with angles of 7 , 10 , 15 and 20 were implanted in stages and different combinations, starting with single-level constructs (C5-6), followed by two (C5-7), and three-level (C4-7) constructs. Radiographs were taken intact and after each stage of implantation. Measurements included segmental lordosis at each level between C2-7, Occ-C2 angle and SVA.
P65. Surgical Treatment of Scoliosis in Marfan Syndrome: Anterior Combined with Posterior Approach versus Posterior-Only Approach Xiao Han, II1, Jun Qiao, MD2, Zezhang Zhu, PhD3, Feng Zhu, MD3, Bin Wang, MD3, Bangping Qian, MD3, Yang Yu, MD3, Yong Qiu, MD3; 1 Nanjing, China; 2Nanjing Gulou Hospital, Nanjing, Jiangsu, China; 3The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, China BACKGROUND CONTEXT: Scoliosis is the most commonly seen skeletal disorder associated with Marfan syndrome. Surgical treatment is applied to most of these patients. PURPOSE: To compare surgical outcomes of scoliosis associated with Marfan syndrome between anterior combined with posterior approach versus posterior-only approach. STUDY DESIGN/SETTING: A retrospective review was performed on the records of patients with Marfan syndrome from one single institution from 1998 to 2012. PATIENT SAMPLE: Inclusion criteria were patients who were 10 to 20 years of age, had a diagnosis of Marfan syndrome by the Ghent nosology, had scoliosis and had undergone spinal fusion, and had at least 2 years of postoperative follow-up. METHODS: The medical records of all patients were reviewed for age at the time of surgery, surgical procedures performed, instrumentation type, estimated blood loss (EBL) during surgery, operation time and complications related to surgery. Health-related quality-of-life measures (obtained with the SRS-22 Questionnaire before operation and at the last clinical follow-up) were also recorded. Patients were analyzed as two different groups, Group 1 and Group 2, according to the different approaches employed. Patients receiving combined anterior and posterior surgery were assigned to Group 1 and those who received posterioronly to Group 2. RESULTS: Group 1 consisted of 30 patients (42 males, 54 females) with a mean age at surgery of 16.8 years (range: 10 - 20). Complications in Group 1 included 2 cases of instrumentation loosening with 1 removed, 1 case of instrumentation breakage and 1 case of chylothorax and hemothorax
Refer to onsite Annual Meeting presentations and postmeeting proceedings for possible referenced figures and tables. Authors are responsible for accurately reporting disclosures and FDA device/drug status at time of abstract submission.