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Risk Factors of Lumbar Spinal Epidural Lipomatosis
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NASS 32nd Annual Meeting Proceedings / The Spine Journal 17 (2017) S111–S165
PURPOSE: To retrospectively study the relationships between cadaveric lumbar spinal motion segments and their biomechanical characteristics. STUDY DESIGN/SETTING: Standard nondestructive flexibility tests were performed on intact lumbar spine segments. Relationships between donor spine features and in vitro ranges of motion (ROM) were studied using Pearson correlation analyses. PATIENT SAMPLE: A total of 282 cadaveric lumbar motion segments (from L1 to S) from 85 donor spines [47 M/38 F, range: 21–73 years, mean age 54.1+/-10.9 years, BMD 0.819+/-0.169 g/cm2, mean subject height 1.73+/-0.09 m.]. OUTCOME MEASURES: Spinal flexibility of intact motion segments was assessed using intervertebral mean range of motion (ROM) during flexionextension, lateral bending and axial rotation. METHODS: General spine tissue donor information (age, gender and height) was obtained from medical histories provided by tissue banks. Vertebral body heights, disc heights, and bone mineral densities (BMD) were determined from X-ray images and DEXA scans of the dissected spines. Kinematic data were retrieved from studies involving intact testing of the fresh frozen lumbar spine segments (L1 through S), with all tests performed in the same lab and using the same methods. Loads of 7.5 Nm were applied while measuring intervertebral flexion-extension (FL-EX), lateral bending (Lat Bend, average right and left), and axial rotation (Ax Rot, average right and left), optoelectronically. Relationships between donor information (subject height), spine segment features (BMD, vertebral body height, disc height) and ROM were studied using Pearson correlation analysis (p<.05). RESULTS: There were significant negative correlations between ROM and subject height (FL-EX: R=-0.124, p=.043; Ax Rot: R=-0.180, p=.003); and Lat Bend: R=-0.152, p=.012), as well as ROM and disc height (FLEX: R=-0.178, p=.015; Ax Rot: R=-0.229, p=.002; Lat Bend: R=-0.173, p=.018). Other significant correlations with ROM include: donor age [Ax Rot: R=0.243, p<.001], BMD [all directions of motion: R<-0.16, p<.007], and vertebral body height [FL-EX: R=0.186, p=.006, and Lat Bend: R=0.136, p=.046]. There were no relationships between ROM and donor age during FL-EX (R=-0.016, p=.791) or Lat Bend (R=0.023, p=.700). Similarly, there was no correlation between ROM and body height during Ax Rot (R=0.094, p=.170). CONCLUSIONS: Significant relationships exist between lumbar spine segments’ geometric, material and biomechanical properties (ROM). These factors need to be considered during the validation process of finite element models involving human lumbar spine segments. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
PURPOSE: Estimate the temporal trends in both numbers and complexities of LSS surgery; estimate the major medical and wound complications and health resources use of LSS surgery. STUDY DESIGN/SETTING: Retrospective review of administrative claims from 2010 – 2014 Marketscan commercial claims database. PATIENT SAMPLE: Based on ICD-9CM diagnosis and procedure codes, we identified 28,986 patients over the age of 40 years and undergoing decompressive surgery with or without arthrodesis for LSS. These participants were middle age (mean 56 standard deviation (SD) 6.0 years); with comorbid conditions (mean Charlson 0.44 SD 0.79); and of balanced gender (50% female). Race and ethnicity are not captured. OUTCOME MEASURES: Rate and complexity (decompression alone, plus simple fusion, plus complex fusion) of LSS surgery, complications (major medical and wound), health use, and total charges were estimated. Simple fusion involved a single surgical approach and only 1 or 2 disc levels. Complex fusion involved 360° fusion, combination of approaches, or >2 disc levels. Health use included discharge to skilled nursing (SNF) and 30-day readmission. METHODS: Surgical rate and complexity were estimated by ratio of number and type of cases:enrolled beneficiaries. Poisson regression modeled trends over time. Logistic regression estimated likelihood of complication, discharge to SNF, and 30-day readmission. Linear regression estimated length of stay and total charges. Models were adjusted for age, gender and comorbidity. RESULTS: Overall, surgical rates have decreased (14.9 to 11.3 per 100,000); however, the rate of complex fusions has increased (0.30 to 1.24 per 100,000) (p<.001). Length of stay has not increased (median 2 days) but total charges have increased 150% ($21776 to $32616) (p<.001). Major medical complication increased over time (1.4% to 1.7%, p<.001), but wound complication did not (average 1.0%). Fusion procedures (both simple and complex) were associated with higher complications compared to simple fusion (p<.01). Discharge to SNF decreased over time (2.0% to 2.9%, p<.001); however, 30-day readmission did not (average 5.7%). Fusion was associated with increased discharge to SNF (p<.001) and 30-day readmission (p<.02). CONCLUSIONS: Similar to Medicare patients, surgery to manage LSS in older working aged adults has become more complex and expensive. Fusion procedures are associated with increased consumption of health care resources. Surgeons should consider less invasive procedures to minimize risk and health care resource use. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
https://doi.org/10.1016/j.spinee.2017.07.236
https://doi.org/10.1016/j.spinee.2017.07.238
Friday, October 27, 2017 10:45 AM – 12:00 PM Lumbar Stenosis 190. Lumbar Spinal Stenosis in Working-Aged Older Adults: Trends, Complications, and Charges Richard L. Skolasky, ScD1, Brian J. Neuman, MD2, Lee H. Riley III, MD3; 1Johns Hopkins University, Baltimore, MD, USA; 2 Baltimore, MD, USA; 3Johns Hopkins Outpatient Center/Department of Orthopedic Surgery, Baltimore, MD, USA BACKGROUND CONTEXT: Typically, lumbar spinal stenosis (LSS) becomes symptomatic after the age of 50. Failing conservative treatment, decompressive surgery has been shown to be beneficial to alleviate pain and improve function. Among the Medicare population, surgeries for LSS are becoming more common and more complex. This increase may be driven by introduction and marketing of new devices and by key opinion leaders. The extent to which these factors may drive the experience of workingaged adults with LSS, however, is unknown.
191. Risk Factors of Lumbar Spinal Epidural Lipomatosis Anuj Patel, MD1, Catphuong L. Vu, MD, MPH2, Weilong J. Shi, MD3, Douglas D. Robertson Jr., MD, PhD4, John M. Rhee, MD1; 1Emory University, Atlanta, GA, USA; 2University of Washington, Seattle, WA, USA; 3Emory Orthopaedics, Duluth, GA, USA; 4Emory Orthopaedics and Spine Center, Atlanta, GA, USA BACKGROUND CONTEXT: Spinal epidural lipomatosis (SEL) is an excessive amount of adipose tissue within the epidural space that deforms the thecal sac. SEL can cause central spinal stenosis by directly compressing the thecal sac. Even without causing direct compression, excessive epidural fat can lead to symptoms by decreasing the accommodating ability of the epidural space. It is possible that otherwise clinically insignificant spinal pathology can then become acutely symptomatic. PURPOSE: Our aim is to establish a reliable method to measure epidural adipose tissue so that we may determine which risk factors and symptoms correlate with excessive deposition of adipose tissue in the epidural space. STUDY DESIGN/SETTING: We performed a retrospective review of a consecutive cohort of 248 new adult spine patients. PATIENT SAMPLE: A total of 248 new adult spine patients.
NASS 32nd Annual Meeting Proceedings / The Spine Journal 17 (2017) S111–S165 OUTCOME MEASURES: Statistical analysis was then performed to determine the relationship of volume of lumbar epidural fat to chief complaint, age, sex, BMI, pain scores, posterior subcutaneous fat, number of epidural steroid injections within a year, HBA1c, LDL, HDL, and triglycerides. METHODS: The quantity of epidural fat was measured on MRI T1 weighted images. Measurements were taken on axial and sagittal cuts. MRI measurements were also performed using a program created at our institution to volumetrically quantify the amount of fat in the epidural space of the lumbar spine based on axial cuts. Axial cuts starting at the level of the lamina of L1 caudally to the level of the lamina of S1 were measured. An intra and inter-observer reliability study was performed to validate the measurements from the program. RESULTS: The program created to quantify the total volume of epidural fat was found to be extremely reliable, with an inter-observer correlation coefficient of 0.980 (95% CI: 0.961–0.991) and an intra-observer correlation coefficient of 0.995 (95% CI: 0.990–0.999). Several risk factors were found to directly correlate with the volume of epidural adipose tissue in the lumbar spine. There was a direct correlation between patients’ BMI and their total volume of epidural fat (p<.0001); patients grouped by the WHO BMI classification system in turn also had significantly different means of volume of epidural fat (p<.0001). HbA1c and the depth of posterior subcutaneous fat were also found to be directly correlated to the total volume of epidural fat (p=.021, p<.0001, respectively). Increasing volumes of lumbar epidural fat directly correlated with increasing pain scores (p=.001). Of total patients, 67% (163/143) were found to have SEL, defined as direct deformation of their thecal sac by epidural fat. The mean volume of epidural fat was significantly higher in patients with SEL at 7467.25 mm3 compared to those without SEL at 5016.30 mm3 (p<.0001). The mean BMI of patients with SEL was significantly higher at 31.47±5.07 than in patients without SLE at 25.55±3.37 (p<.0001). There is also a higher probability that patients with diabetes had SEL compared to non-diabetics (p=.0052). There is a difference between odds of having SEL among patients with different chief complaints (p=.0345). Lastly, patients with SEL had a higher average pain score of 6.03 than patients without SEL of 4.41 (p<.0001). CONCLUSIONS: We defined spinal epidural lipomatosis as an excessive amount of adipose tissue within the epidural space that deforms the thecal sac. The program created at Emory University to volumetrically quantify epidural fat was reliable despite various levels of observer training. We determined that SEL in the lumbar spine was more commonly found in patients with a greater total volume of epidural adipose tissue. BMI, HbA1c, and posterior subcutaneous fat were all found to directly correlate with the total volume of epidural fat in the lumbar spine. Total volume of epidural fat and the presence of SEL directly correlated with patient pain scores. Although further studies must be performed, it is possible that early identification and prevention of these risk factors may decrease the risk of symptomatic spinal pathology. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2017.07.239
192. Hospital Readmission following Spinal Laminectomy Procedures Throughout the United States Joseph L. Laratta, MD1, Jamal Shillingford, MD1, Joseph M. Lombardi, MD1, Jeffrey L. Gum, MD2, Steven D. Glassman, MD2, Lawrence G. Lenke, MD1, Ronald A. Lehman Jr., MD1; 1The Spine Hospital at Columbia University Medical Center, New York, NY, USA; 2Norton Leatherman Spine Center, Louisville, KY, USA BACKGROUND CONTEXT: Laminectomy is one of the most commonly performed procedures in spine surgery. To evaluate health care utilization and allocation of resources, it is essential to understand the demographic and economic data surrounding readmissions associated with laminectomy procedures performed in the US.
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PURPOSE: We hypothesized that the rate of readmission associated with spinal laminectomy procedures has decreased over the recent decade, while the costs of readmission have increased. STUDY DESIGN/SETTING: Retrospective cohort. PATIENT SAMPLE: Patients undergoing a spinal laminectomy procedure during the years of 2009–2014. OUTCOME MEASURES: Economic and demographic data. METHODS: The Healthcare Cost and Utilization Project Nationwide Readmissions Database (NRD) was queried for patients undergoing a spinal laminectomy procedure during the years of 2009–2014. The NRD database includes discharges for patients with and without repeat hospital visits in a year and is weighted to provide national estimates. Demographic and economic data were obtained which included the age, sex, insurance type, location, frequency of readmission and cost per stay. RESULTS: A total of 396,600 index stays involved a laminectomy during 2014. An estimated 25,440 patients required readmission within 30 days for any cause (6.4%). The readmission rate was constant over the study period (range, 6.3–6.5). The mean cost per stay for the index procedure increased 24.0% from $19,339 in 2009 to $23,983 in 2014. The mean cost per stay for the readmission increased 19.3% from $13,005 in 2009 to $15,512 in 2014. The greatest number of readmissions occurred in patients older than 65 years (8.0%). Based on insurance status, Medicare and Medicaid were more likely to be readmitted than private payers (8.2% vs 8.1% vs 4.5%, respectively). When stratifying by median income for patient zip code, there was no difference in the rate of readmission across all groups. CONCLUSIONS: Over the past six years, the rate of readmission for spinal laminectomy procedures has remained constant, while the cost of index and readmission stays has increased significantly. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2017.07.240
193. Validation and Utility of the Patient-Reported Outcomes Measurement Information System (PROMIS®) in Patients with Lumbar Stenosis with or without Spondylolisthesis Hemil Maniar, MD1, Wellington K. Hsu, MD2, Surabhi Bhatt, BS3, Jason W. Savage, MD4, Alpesh A. Patel, MD, FACS5; 1Geisinger Health Systems, Danville, PA, USA; 2Northwestern University, Chicago, IL, USA; 3 Northwestern University School of Medicine, Chicago, IL, USA; 4Plano, TX, USA; 5Northwestern Department of Orthopaedics, Chicago, IL, USA BACKGROUND CONTEXT: Lumbar stenosis is a clinical syndrome caused by narrowing of the spinal canal characterized by back and leg pain. A subset of patients with lumbar stenosis have spondylolisthesis. Surgical decompression with laminectomy is a current standard of care with good outcomes, however, there is controversy regarding treatment of patients who have associated spondylolisthesis especially regarding whether to perform a spinal fusion in addition to decompression. Patient-reported outcomes used in studies comparing these surgical procedures utilize legacy measures including but not limited to ODI (Oswestry Disability Index), VAS (Visual Analog Scale), ZCQ (Zurich Claudication Questionnaire), SF -12 (short form), etc, that are administered on paper forms, time consuming, inaccurate and have floor/ceiling effects. PROMIS uses a computer adaptive testing (CAT) model whereby questions are programmed as per answers to previous questions. PURPOSE: To validate and assess the utility of the PROMIS® Physical Function, Pain Interference, and Pain Behavior CATs in comparing surgical outcomes of patients with lumbar stenosis with or without degenerative spondylolisthesis. STUDY DESIGN/SETTING: Patients were divided into two groups depending on presence or absence of spondylolisthesis. Patients with spondylolisthesis were treated with an instrumented fusion in addition to laminectomy. PATIENT SAMPLE: A total of 69 patients with lumbar stenosis were included in this prospective study.
NASS 32nd Annual Meeting Proceedings / The Spine Journal 17 (2017) S111–S165
PURPOSE: To retrospectively study the relationships between cadaveric lumbar spinal motion segments and their biomechanical characteristics. STUDY DESIGN/SETTING: Standard nondestructive flexibility tests were performed on intact lumbar spine segments. Relationships between donor spine features and in vitro ranges of motion (ROM) were studied using Pearson correlation analyses. PATIENT SAMPLE: A total of 282 cadaveric lumbar motion segments (from L1 to S) from 85 donor spines [47 M/38 F, range: 21–73 years, mean age 54.1+/-10.9 years, BMD 0.819+/-0.169 g/cm2, mean subject height 1.73+/-0.09 m.]. OUTCOME MEASURES: Spinal flexibility of intact motion segments was assessed using intervertebral mean range of motion (ROM) during flexionextension, lateral bending and axial rotation. METHODS: General spine tissue donor information (age, gender and height) was obtained from medical histories provided by tissue banks. Vertebral body heights, disc heights, and bone mineral densities (BMD) were determined from X-ray images and DEXA scans of the dissected spines. Kinematic data were retrieved from studies involving intact testing of the fresh frozen lumbar spine segments (L1 through S), with all tests performed in the same lab and using the same methods. Loads of 7.5 Nm were applied while measuring intervertebral flexion-extension (FL-EX), lateral bending (Lat Bend, average right and left), and axial rotation (Ax Rot, average right and left), optoelectronically. Relationships between donor information (subject height), spine segment features (BMD, vertebral body height, disc height) and ROM were studied using Pearson correlation analysis (p<.05). RESULTS: There were significant negative correlations between ROM and subject height (FL-EX: R=-0.124, p=.043; Ax Rot: R=-0.180, p=.003); and Lat Bend: R=-0.152, p=.012), as well as ROM and disc height (FLEX: R=-0.178, p=.015; Ax Rot: R=-0.229, p=.002; Lat Bend: R=-0.173, p=.018). Other significant correlations with ROM include: donor age [Ax Rot: R=0.243, p<.001], BMD [all directions of motion: R<-0.16, p<.007], and vertebral body height [FL-EX: R=0.186, p=.006, and Lat Bend: R=0.136, p=.046]. There were no relationships between ROM and donor age during FL-EX (R=-0.016, p=.791) or Lat Bend (R=0.023, p=.700). Similarly, there was no correlation between ROM and body height during Ax Rot (R=0.094, p=.170). CONCLUSIONS: Significant relationships exist between lumbar spine segments’ geometric, material and biomechanical properties (ROM). These factors need to be considered during the validation process of finite element models involving human lumbar spine segments. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
PURPOSE: Estimate the temporal trends in both numbers and complexities of LSS surgery; estimate the major medical and wound complications and health resources use of LSS surgery. STUDY DESIGN/SETTING: Retrospective review of administrative claims from 2010 – 2014 Marketscan commercial claims database. PATIENT SAMPLE: Based on ICD-9CM diagnosis and procedure codes, we identified 28,986 patients over the age of 40 years and undergoing decompressive surgery with or without arthrodesis for LSS. These participants were middle age (mean 56 standard deviation (SD) 6.0 years); with comorbid conditions (mean Charlson 0.44 SD 0.79); and of balanced gender (50% female). Race and ethnicity are not captured. OUTCOME MEASURES: Rate and complexity (decompression alone, plus simple fusion, plus complex fusion) of LSS surgery, complications (major medical and wound), health use, and total charges were estimated. Simple fusion involved a single surgical approach and only 1 or 2 disc levels. Complex fusion involved 360° fusion, combination of approaches, or >2 disc levels. Health use included discharge to skilled nursing (SNF) and 30-day readmission. METHODS: Surgical rate and complexity were estimated by ratio of number and type of cases:enrolled beneficiaries. Poisson regression modeled trends over time. Logistic regression estimated likelihood of complication, discharge to SNF, and 30-day readmission. Linear regression estimated length of stay and total charges. Models were adjusted for age, gender and comorbidity. RESULTS: Overall, surgical rates have decreased (14.9 to 11.3 per 100,000); however, the rate of complex fusions has increased (0.30 to 1.24 per 100,000) (p<.001). Length of stay has not increased (median 2 days) but total charges have increased 150% ($21776 to $32616) (p<.001). Major medical complication increased over time (1.4% to 1.7%, p<.001), but wound complication did not (average 1.0%). Fusion procedures (both simple and complex) were associated with higher complications compared to simple fusion (p<.01). Discharge to SNF decreased over time (2.0% to 2.9%, p<.001); however, 30-day readmission did not (average 5.7%). Fusion was associated with increased discharge to SNF (p<.001) and 30-day readmission (p<.02). CONCLUSIONS: Similar to Medicare patients, surgery to manage LSS in older working aged adults has become more complex and expensive. Fusion procedures are associated with increased consumption of health care resources. Surgeons should consider less invasive procedures to minimize risk and health care resource use. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
https://doi.org/10.1016/j.spinee.2017.07.236
https://doi.org/10.1016/j.spinee.2017.07.238
Friday, October 27, 2017 10:45 AM – 12:00 PM Lumbar Stenosis 190. Lumbar Spinal Stenosis in Working-Aged Older Adults: Trends, Complications, and Charges Richard L. Skolasky, ScD1, Brian J. Neuman, MD2, Lee H. Riley III, MD3; 1Johns Hopkins University, Baltimore, MD, USA; 2 Baltimore, MD, USA; 3Johns Hopkins Outpatient Center/Department of Orthopedic Surgery, Baltimore, MD, USA BACKGROUND CONTEXT: Typically, lumbar spinal stenosis (LSS) becomes symptomatic after the age of 50. Failing conservative treatment, decompressive surgery has been shown to be beneficial to alleviate pain and improve function. Among the Medicare population, surgeries for LSS are becoming more common and more complex. This increase may be driven by introduction and marketing of new devices and by key opinion leaders. The extent to which these factors may drive the experience of workingaged adults with LSS, however, is unknown.
191. Risk Factors of Lumbar Spinal Epidural Lipomatosis Anuj Patel, MD1, Catphuong L. Vu, MD, MPH2, Weilong J. Shi, MD3, Douglas D. Robertson Jr., MD, PhD4, John M. Rhee, MD1; 1Emory University, Atlanta, GA, USA; 2University of Washington, Seattle, WA, USA; 3Emory Orthopaedics, Duluth, GA, USA; 4Emory Orthopaedics and Spine Center, Atlanta, GA, USA BACKGROUND CONTEXT: Spinal epidural lipomatosis (SEL) is an excessive amount of adipose tissue within the epidural space that deforms the thecal sac. SEL can cause central spinal stenosis by directly compressing the thecal sac. Even without causing direct compression, excessive epidural fat can lead to symptoms by decreasing the accommodating ability of the epidural space. It is possible that otherwise clinically insignificant spinal pathology can then become acutely symptomatic. PURPOSE: Our aim is to establish a reliable method to measure epidural adipose tissue so that we may determine which risk factors and symptoms correlate with excessive deposition of adipose tissue in the epidural space. STUDY DESIGN/SETTING: We performed a retrospective review of a consecutive cohort of 248 new adult spine patients. PATIENT SAMPLE: A total of 248 new adult spine patients.
NASS 32nd Annual Meeting Proceedings / The Spine Journal 17 (2017) S111–S165 OUTCOME MEASURES: Statistical analysis was then performed to determine the relationship of volume of lumbar epidural fat to chief complaint, age, sex, BMI, pain scores, posterior subcutaneous fat, number of epidural steroid injections within a year, HBA1c, LDL, HDL, and triglycerides. METHODS: The quantity of epidural fat was measured on MRI T1 weighted images. Measurements were taken on axial and sagittal cuts. MRI measurements were also performed using a program created at our institution to volumetrically quantify the amount of fat in the epidural space of the lumbar spine based on axial cuts. Axial cuts starting at the level of the lamina of L1 caudally to the level of the lamina of S1 were measured. An intra and inter-observer reliability study was performed to validate the measurements from the program. RESULTS: The program created to quantify the total volume of epidural fat was found to be extremely reliable, with an inter-observer correlation coefficient of 0.980 (95% CI: 0.961–0.991) and an intra-observer correlation coefficient of 0.995 (95% CI: 0.990–0.999). Several risk factors were found to directly correlate with the volume of epidural adipose tissue in the lumbar spine. There was a direct correlation between patients’ BMI and their total volume of epidural fat (p<.0001); patients grouped by the WHO BMI classification system in turn also had significantly different means of volume of epidural fat (p<.0001). HbA1c and the depth of posterior subcutaneous fat were also found to be directly correlated to the total volume of epidural fat (p=.021, p<.0001, respectively). Increasing volumes of lumbar epidural fat directly correlated with increasing pain scores (p=.001). Of total patients, 67% (163/143) were found to have SEL, defined as direct deformation of their thecal sac by epidural fat. The mean volume of epidural fat was significantly higher in patients with SEL at 7467.25 mm3 compared to those without SEL at 5016.30 mm3 (p<.0001). The mean BMI of patients with SEL was significantly higher at 31.47±5.07 than in patients without SLE at 25.55±3.37 (p<.0001). There is also a higher probability that patients with diabetes had SEL compared to non-diabetics (p=.0052). There is a difference between odds of having SEL among patients with different chief complaints (p=.0345). Lastly, patients with SEL had a higher average pain score of 6.03 than patients without SEL of 4.41 (p<.0001). CONCLUSIONS: We defined spinal epidural lipomatosis as an excessive amount of adipose tissue within the epidural space that deforms the thecal sac. The program created at Emory University to volumetrically quantify epidural fat was reliable despite various levels of observer training. We determined that SEL in the lumbar spine was more commonly found in patients with a greater total volume of epidural adipose tissue. BMI, HbA1c, and posterior subcutaneous fat were all found to directly correlate with the total volume of epidural fat in the lumbar spine. Total volume of epidural fat and the presence of SEL directly correlated with patient pain scores. Although further studies must be performed, it is possible that early identification and prevention of these risk factors may decrease the risk of symptomatic spinal pathology. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2017.07.239
192. Hospital Readmission following Spinal Laminectomy Procedures Throughout the United States Joseph L. Laratta, MD1, Jamal Shillingford, MD1, Joseph M. Lombardi, MD1, Jeffrey L. Gum, MD2, Steven D. Glassman, MD2, Lawrence G. Lenke, MD1, Ronald A. Lehman Jr., MD1; 1The Spine Hospital at Columbia University Medical Center, New York, NY, USA; 2Norton Leatherman Spine Center, Louisville, KY, USA BACKGROUND CONTEXT: Laminectomy is one of the most commonly performed procedures in spine surgery. To evaluate health care utilization and allocation of resources, it is essential to understand the demographic and economic data surrounding readmissions associated with laminectomy procedures performed in the US.
S137
PURPOSE: We hypothesized that the rate of readmission associated with spinal laminectomy procedures has decreased over the recent decade, while the costs of readmission have increased. STUDY DESIGN/SETTING: Retrospective cohort. PATIENT SAMPLE: Patients undergoing a spinal laminectomy procedure during the years of 2009–2014. OUTCOME MEASURES: Economic and demographic data. METHODS: The Healthcare Cost and Utilization Project Nationwide Readmissions Database (NRD) was queried for patients undergoing a spinal laminectomy procedure during the years of 2009–2014. The NRD database includes discharges for patients with and without repeat hospital visits in a year and is weighted to provide national estimates. Demographic and economic data were obtained which included the age, sex, insurance type, location, frequency of readmission and cost per stay. RESULTS: A total of 396,600 index stays involved a laminectomy during 2014. An estimated 25,440 patients required readmission within 30 days for any cause (6.4%). The readmission rate was constant over the study period (range, 6.3–6.5). The mean cost per stay for the index procedure increased 24.0% from $19,339 in 2009 to $23,983 in 2014. The mean cost per stay for the readmission increased 19.3% from $13,005 in 2009 to $15,512 in 2014. The greatest number of readmissions occurred in patients older than 65 years (8.0%). Based on insurance status, Medicare and Medicaid were more likely to be readmitted than private payers (8.2% vs 8.1% vs 4.5%, respectively). When stratifying by median income for patient zip code, there was no difference in the rate of readmission across all groups. CONCLUSIONS: Over the past six years, the rate of readmission for spinal laminectomy procedures has remained constant, while the cost of index and readmission stays has increased significantly. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs. https://doi.org/10.1016/j.spinee.2017.07.240
193. Validation and Utility of the Patient-Reported Outcomes Measurement Information System (PROMIS®) in Patients with Lumbar Stenosis with or without Spondylolisthesis Hemil Maniar, MD1, Wellington K. Hsu, MD2, Surabhi Bhatt, BS3, Jason W. Savage, MD4, Alpesh A. Patel, MD, FACS5; 1Geisinger Health Systems, Danville, PA, USA; 2Northwestern University, Chicago, IL, USA; 3 Northwestern University School of Medicine, Chicago, IL, USA; 4Plano, TX, USA; 5Northwestern Department of Orthopaedics, Chicago, IL, USA BACKGROUND CONTEXT: Lumbar stenosis is a clinical syndrome caused by narrowing of the spinal canal characterized by back and leg pain. A subset of patients with lumbar stenosis have spondylolisthesis. Surgical decompression with laminectomy is a current standard of care with good outcomes, however, there is controversy regarding treatment of patients who have associated spondylolisthesis especially regarding whether to perform a spinal fusion in addition to decompression. Patient-reported outcomes used in studies comparing these surgical procedures utilize legacy measures including but not limited to ODI (Oswestry Disability Index), VAS (Visual Analog Scale), ZCQ (Zurich Claudication Questionnaire), SF -12 (short form), etc, that are administered on paper forms, time consuming, inaccurate and have floor/ceiling effects. PROMIS uses a computer adaptive testing (CAT) model whereby questions are programmed as per answers to previous questions. PURPOSE: To validate and assess the utility of the PROMIS® Physical Function, Pain Interference, and Pain Behavior CATs in comparing surgical outcomes of patients with lumbar stenosis with or without degenerative spondylolisthesis. STUDY DESIGN/SETTING: Patients were divided into two groups depending on presence or absence of spondylolisthesis. Patients with spondylolisthesis were treated with an instrumented fusion in addition to laminectomy. PATIENT SAMPLE: A total of 69 patients with lumbar stenosis were included in this prospective study.