Faculty Bibliography

BACKGROUND CONTEXT: Persistent lumbopelvic malalignment following ASD-corrective surgery may impair quality of life and result in persistent pathologic compensation in the lower extremities. Patient-specific age- and BMI-adjusted alignment targets have been proposed to improve alignment outcomes; however, it is unclear whether reaching these postop targets reduces rates of pelvic nonresponse following surgery. PURPOSE: Assess the relationship between pelvic nonresponse to ASD-corrective surgery and persistent lower-extremity compensation. STUDY DESIGN/SETTING: Single center retrospective review. PATIENT SAMPLE: Fifty-eight ASD patients. OUTCOME MEASURES: Sagittal alignment.
METHOD(S): Included: surgical ASD patients with full-spine X-ray imaging at pre- and early postop follow-up (<1Y). Patients were grouped by postop improvement in PT, per SRS-Schwab Classification: those who did not improve (pelvic nonresponders, PNR), and those that did improve (pelvic responders, PR). Groups were propensity score matched for preop PT, and assessed for differences in demographics, surgical factors, and alignment (sagittal spinal and lower extremity) with means comparison tests. Rates of persistent postop lower extremity compensation (defined as no improvement in lower extremity alignment) were compared between groups. Subanalysis assessed the relationship between reaching postop age- and BMI-specific alignment targets and rates of pelvic nonresponse.
RESULT(S): Following propensity score matching, PNR (N=29) and PR (N=29) patients did not differ in age, sex, BMI or preop sagittal spinal alignment (all p>0.05); however, PNR patients presented with less knee flexion (9degree vs 14degree, p=0.043). Groups did not differ in levels fused (10.8 vs 10.8, p=0.974) or osteotomy (93% vs 92%, p=0.902). Postop, PNR patients had inferior lumbopelvic alignment in PT (30degree vs 17degree), PI-LL (17degree vs 3degree), and greater global malalignment for TPA (27degree vs 15degree, all p<0.001). For PNR patients, these changes in alignment were accompanied by greater compensatory anterior hip extension (53mm vs 31mm, p=0.021). PNR patients also showed greater pre- to postop increases in sacrofemoral angle (2degree vs -5degree), and smaller decreases in hip extension (-24mm vs -64mm), pelvic femoral angle (-1.4degree vs -3.8degree), and global sagittal angle (-3.5degree vs -8degree, all p<0.005), indicating persistent lower extremity compensation. PNR patients had higher rates of persistent postop lower extremity compensation for sacrofemoral angle (68% vs 25%), ankle flexion (64% vs 33%), and pelvic shift (28% vs 4%, all p<0.034). PNR and PR groups did not differ in rates of reaching age- and BMI specific ideal postop alignment for PT, SVA, TPA, or PI-LL (all p>0.05). For patients with severe preop SVA deformity, overcorrection relative to ideal postop PT targets was associated with lower rates of pelvic non-response (under: 12%, match: 18%, over: 71%, p<0.001). Lower rates of nonresponse were observed for patients with severe preop PT deformity overcorrected relative to ideal postop PI-LL (under: 0%, match: 30%, over: 70%, p=0.016).
CONCLUSION(S): Pelvic nonresponders following ASD-corrective surgery had higher rates of persistent compensatory action in the lower extremities. Patients with severe preop PT deformity who were surgically overcorrected with respect to ideal PI-LL had lower rates of postop pelvic nonresponse, indicating that for severely malalignmed patients, existing alignment targets may need to be adjusted to optimize alignment outcomes. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Adult spinal deformity (ASD) surgery often involves complex deformity correction. It's unknown which baseline (BL) patient factors predict lower total costs in ASD surgery. PURPOSE: Identify predictors of lower total surgery costs for ASD patients. STUDY DESIGN/SETTING: Retrospective review of a prospective multicenter adult spinal deformity database. PATIENT SAMPLE: A total of 311 operative ASD patients >=18 years old with baseline and 3Y demographic, surgical, and frailty data. OUTCOME MEASURES: Schwab sagittal vertebral axis (SVA) modifier grade, Owestry Disability Index (ODI), costs of ASD surgery, predictors of lower costs.
METHOD(S): Inclusion criteria included surgical ASD (scoliosis >=20degree, SVA >=5cm, PT >=25degree, or thoracic kyphosis >=60degree) patients >18 years with available frailty, demographic, and radiographic data at BL and 1 year postop. Descriptive analyses assessed mean age, frailty, and surgical data. Total costs for surgery were calculated using the PearlDiver database. A conditional variable importance table used nonreplacement sampling set of 20,000 conditional inference trees to identify the top factors associated with lower cost surgery for low (LSVA), moderate (MSVA), and high (HSVA) Schwab modifier grades. LSVA were SVA<4 cm, MSVA 4 cm-9.5 cm, HSVA were >9.5 cm. Linear and logistic regression assessed the relationship between significant predictors and the odds of lower cost surgery.
RESULT(S): Of the 322 total ASD patients, 322 met inclusion criteria. Descriptive statistics were: age 58.9 +/- 14.9, 76% women, BMI 27.8 +/- 6.2, 62% osteotomy, 54% decompression, and 11.0 +/- 4.1 average levels fused. At 3yrfollow-up, the potential cost of ASD surgery ranged from $57,606.88 to $116,312.54. There were 152 LSVA patients, 53 MSVA patients, and 111 HSVA patients. For all patients, BL ODI < 50 (2.22 [1.53-3.23], p<0.001), BL SRS Activity >1.5 (2.62 [1.402-4.875], p=0.002], no previous spine surgery (1.77 [1.22-2.58], p=0.003), frailty scores <0.19 (2.92 [1.69-5.08], p<0.001), no SVA modifiers (1.59 [1.09-2.33], p=0.017), no PI-LL modifiers (1.62 [1.10-2.40] p=0.015), invasiveness scores below 80.8 (1.51 [1.02-2.24] p=0.04), and no depression (1.55 [1.03-2.31] p=0.03) were predictive of lower costs. For LSVA patients specifically, no osteoporosis (7.87 [2.47-25.09] p=<0.001), SRS activity >1.5 (6.76 [1.68-27.18] p=0.007), age <64 (4.37 [1.74-10.99] p=0.002), BL ODI <50 (2.83 [1.14-7.04] p=0.025), SRS total scores >2.38 (3.93 [1.54-10.18] p=0.004), frailty scores <0.37 (2.74 [1.07-6.99] p=0.035), and increasing invasiveness (1.01 [1.00-1.03] p=0.041) were predictive of lower costs. For MSVA patients, invasiveness <94.16 (9.82 [1.00-104.17] p=0.058), no cancer (16.00 [0.80-42.5] p=0.071), and frailty scores <0.3 (3.8 [0.48-30.42] p=0.21) trended towards lower costs. For HSVA, no history of smoking (4.50 [0.90-22.47] p=0.06) and BMI <27.8 (2.84 [0.94-8.60] p=0.06) trended towards lower costs.
CONCLUSION(S): For ASD patients, low frailty, no prior spine surgery, no depression, and higher baseline SRS activity scores were predictive of lower total surgery costs. When assessed by baseline deformity, decreased frailty and the lack of comorbidities and risk factors such as cancer, smoking, or high BMI, were associated with lower costs. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: The efficacy of surgical intervention for central cord syndrome (CCS) is shown in the literature; however, it is unclear whether disparities in patient presentation and treatment exist between those who initially undergo operative treatment and those who delay operative treatment. PURPOSE: In a population of CCS patients, assess disparities in presentation and treatment between those undergoing immediate surgery and those who delay operative treatment. STUDY DESIGN/SETTING: Retrospective analysis of New York State Inpatient Database years 2004-2013. PATIENT SAMPLE: A total of 1,301 CCS patients (ICD-9 codes 952.03, 952.08, 952.13, 952.18). OUTCOME MEASURES: Time to surgery, length of stay (LOS).
METHOD(S): Patient-specific linkage codes allowed longitudinal tracking of inpatient stays within the study period. Demographics, comorbidities (Charlson Comorbidity Index [CCI]), complications, and surgical factors, including Mirza invasiveness score, were compared between CCS patients that initially underwent surgery (Initial) and patients that delayed operative treatment (Delayed) using Chi-squared tests and independent samples t-tests as appropriate. Similar tests assessed differences in demographics and comorbidity burden between nonoperative patients and surgical crossover patients.
RESULT(S): Included: 1,301 CCS patients (62+/-16 yrs, 27% female). Follow-up rate was 67.3%; mean follow-up time was 515+/-707 days. By level of CCS injury, 61.0% of patients were injured between C1 and C4, 59.2% between C5-C7, 1.0% between T1-T6, and 0.6% between T7-T12. Overall, 800 (61%) patients underwent surgical treatment (procedural breakdown: 80% fusion, 59% decompression, including 38% discectomy and 23% other decompression of the spinal canal). Of the surgical patients, 621 (78%) had surgery at first recorded hospital visit, while 179 (22%) experienced a delay before surgical treatment. For patients that delayed treatment, mean time to surgery was 203+/-358 days. Initial and Delayed patients did not differ in sex (p=0.109) or CCI (p=0.894), though Initial patients were younger than Delayed (60+/-15 yrs vs 63+/-13, p=0.016) and had lower rates of diabetes and valvular disease (both p<0.04). Initial patients underwent more invasive procedures than Delayed (5.1+/-2.6 vs 4.3+/-3.2, p=0.003), including higher rates of fusion (84% vs 71%, p<0.001), but not decompression: overall (59% vs 60%, p=0.816), discectomy (39% vs 35%, p=0.306), other canal decompression (22% vs 27%, p=0.175). LOS was longer for Initial patients (16+/-20 days vs 7+/-10, p<0.001), but complication rates did not differ (all p>0.05). Patients who delayed operative treatment did not differ from nonop patients in age (63+/-13 vs 63+/-17, p=0.802) or CCI (1.04+/-1.49 vs 1.06+/-1.49, p=0.923); however, Delayed patients had higher rates of diabetes (26% vs 18%, p=0.037), neurologic disorders (7% vs 1%, p<0.001), and valvular disease (6% vs 2%, p=0.026) than patients that remained nonoperative.
CONCLUSION(S): Although patients managed with initial surgical treatment of CCS had longer hospital stays and were treated with more invasive procedures, perioperative complications did not differ. Twenty-two percent of CCS patients crossed over from nonoperative to operative treatment, with a mean time to crossover of 203 days. Patients who crossed over to operative care were more comorbid than patients who remained nonoperative, indicating comorbidity burden may play a role in the decision to operate. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Many patients are unable to undergo a major cervical deformity corrective surgery due to deformity severity, age, comorbidities, and overall frailty status. In order to optimize quality of life in patients with cervical deformity, there may be alignment targets to be prioritized. PURPOSE: To prioritize the cervical parameter targets for alignment. STUDY DESIGN/SETTING: Retrospective review of a multicenter prospective cervical deformity database. PATIENT SAMPLE: Seventy-seven patients undergoing cervical deformity (CD) corrective surgery. OUTCOME MEASURES: Cervical regional alignment parameters: cervical sagittal vertical axis(cSVA), cervical lordosis(CL), T1 Slope minus CL(TS-CL), chin brow vertical angle(CBVA), McGregor's slope(MGS), C2-T3 plumb line(C2-T3 SVA), C2-T3 angle, C2 Slope. Health-related quality of life measures: NDI.
METHOD(S): Included:CD patients (C2-C7 Cobb>10degree, CL>10degree, cSVA>4cm, or CBVA>25degree) with full baseline (BL) and 1-year (1Y) radiographic parameters and NDI scores; patients with cervical or cervicothoracic Primary Driver Ames type. Patients with BL Ames classified as low CD for both parameters of cSVA(<4cm) and TS-CL(<15degree) were excluded. Patients assessed: Meeting MCID for NDI(<-15 DELTANDI). Ratios of correction were found for regional parameters (cSVA, CL, T1 Slope, TS-CL, CBVA, MGS, C2-T3 SVA, C2-T3 angle, C2 Slope) categorized by Primary Ames Driver (cervical[C] or cervicothoracic[CT]). Decision tree analysis assessed cut-offs for differences associated with meeting NDI MCID at 1Y.
RESULT(S): Seventy-seven CD patients included (62.1yrs, 64%F, 28.8kg/m2). Average CCI: 0.94, 7% current smokers. By approach, anterior: 19.4%, posterior: 41.6%, combined approach: 39%. Mean anterior levels fused: 3.5, posterior: 8.3, total: 7.5. Average op time: 553.1min; mean EBL: 1128.1ccs. 41.6% met MCID for NDI. A backwards linear regression model including radiographic differences as predictors from BL to 1 year for meeting MCID for NDI demonstrated an R2 of 0.820 (p=0.032) included TS-CL, cSVA, MGS, C2SS, C2-T3 angle, C2-T3 SVA, CL. By primary Ames driver, 67.5% of patients were categorized as C, and 32.5% as CT. Ratios of change in predictors for MCID NDI patients (BL -1Y) for C driver patients: 260.8% MGS, 140.3% CL, 121.2% C2-T3 angle, 49.6% C2 slope, 41.1% cSVA, 20.5% TS-CL, 3.1%C2-T3 SVA. While correction in CT driver patients included: 168.7% CL, 93% MGS, 70.8% C2-T3 angle, 31.1% cSVA, 27.5% C2 slope, 24.9% TS-CL, 13.7% C2-T3 SVA. The ratios were not significant between the two groups(p>0.050). Decision tree analysis determined cut-offs for radiographic change, prioritizing in the following order (based upon ordinal regression values): a correction <=42.5degreeC2-T3 angle (OR: 5.667[1.074-29.891], p=0.041), <35.4degreeCL (OR:4.636[0.857-25.071], p=0.075), >-31.76degreeC2 slope (OR: 3.2 [0.852-12.026], p=0.085), >-11.57mm cSVA (OR: 3.185[1.137-8.917], p=0.027), >-2.16degree MGS (OR: 2.724[0.971-7.636], p=0.057).
CONCLUSION(S): Certain ratios of correction of cervical parameters contribute to improving neck disability. Specific cut-offs of radiographic differences from baseline to 1 year were found prioritizing C2-T3 angle, followed by cervical lordosis, C2 slope, C2-C7 plumb line, and McGregor's slope, all strongly associated with meeting the minimal clinically important difference for the neck disability index score. Prioritizing these radiographic alignment parameters will optimize patient-reported outcomes for patients undergoing cervical deformity surgery. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: The Adult Spinal Deformity Invasiveness Index incorporates deformity-specific components to assess the magnitude of correction. It's unknown how invasiveness relates to outcomes in each frailty state. PURPOSE: Investigate the relationship between increasing invasiveness and outcomes in adult spinal deformity (ASD) surgery in each frailty states. STUDY DESIGN/SETTING: Retrospective review of prospective, consecutively enrolled multicenter ASD database. PATIENT SAMPLE: One hundred ninety-five ASD patients with baseline demographic and surgical details. OUTCOME MEASURES: Invasiveness, frailty, minimal clinically important differences (MCID) for the Oswestry Disability Index, SF-36 Physical Component Scores, and Scoliosis Research Society Scores.
METHOD(S): ASD patients (scoliosis >=20degree, SVA >=5cm, PT >=25degree, or TK >=60degree) with baseline frailty and invasiveness scores. Invasiveness index included: posterior: decompression (1), fusion (2), instrumentation (1); osteotomies: 3-coloumn (14), Ponte (1), interbody fusion: anterior lumbar (8), transforaminal/posterior lumbar (2), iliac fixation (2), revision surgery (3). Invasiveness scores were calculated within different frailty states (not frail, NF, <0.3), frail (F, 0.3-0.5), severely frail (SF, >0.5). Logistic regression analysis assessed the relationship between increasing invasiveness and major complications or reoperations and meeting MCID for any of the measured HRQLs at 3 years. Decision tree analysis assessed thresholds for an invasiveness risk benefit cutoff point, above which experiencing complications or reoperations and not reaching MCID were higher. Significance was set to p<0.05.
RESULT(S): Of the 322 patients, 195 met inclusion criteria. Baseline demographic info: age 59.9+/-14.4, 75% female, BMI 27.8+/-6.2, CCI 1.7+/-1.7. Baseline surgical info: 61% osteotomy, 52% decompression, 11.0+/-4.1 levels fused. There were 98 NF, 65 F, and 30 SF patients. For the entire cohort, binary regression analysis found a significant relationship between increasing invasiveness and experiencing a major complication or reoperation (1.01[1.00-1.02], p=0.01). Within each frailty subgroup, the results were 1.01([1.00-1.03], p=0.05) for NF, 1.01([1.01-1.02], p<0.001) for F, and 1.01 ([1.00-1.01], p=0.02) for SF. When defining no major complications or reoperation and meeting MCID in any HRQL at 3 years as a favorable outcome, decision tree analysis established an invasiveness risk benefit cutoff of 63.9. Patients below this threshold were 1.8 [1.38-2.35] (p<0.001) times more likely to not have a major complication/reoperation and meet MCID at 3 years. Invasiveness above this point was a negative predictor (0.55[0.401-0.754], p<0.001). When factoring in frailty, for NF patients the risk benefit cutoff was 79.3 (2.11[1.39-3.20] (p<0.001), 111 for F (2.62 [1.70-4.06] (p<0.001), and 53.3 for SF (2.35[0.78-7.13] (p=0.13).
CONCLUSION(S): Increasing invasiveness is associated with increased odds of major complications and reoperations. A risk/benefit cutoff for decreasing major complications/reoperations and meeting MCID was found to be 79.3 for NF patients, 111 for F patients, and 53.3 for SF patients. Above these thresholds, increasing invasiveness is associated with increasing the risk of major complications or reoperations and not meeting MCID at 3 years. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Adult spinal deformity (ASD) patients exhibit complex and highly variable pathology. The decision to manage patients operatively is subjective and varies based on training and experience. Machine learning algorithms have shown promise in supporting clinical decision-making. PURPOSE: We sought to develop models capable of accurately discriminating between patients receiving operative vs nonoperative treatment based only on baseline radiographic and clinical data at enrollment. STUDY DESIGN/SETTING: Retrospective analysis of a multicenter, prospectively-defined, consecutive cohort of ASD patients. PATIENT SAMPLE: A total of 1,503 patients were included in this study, divided in a 70:30 split for training and testing. OUTCOME MEASURES: Patients receiving operative treatment were defined as those undergoing surgery up to 1 year after their baseline visit.
METHOD(S): Potential predictors included available demographics, past medical history, HRQoL, and premeasured radiographic parameters from AP and lateral films. Variables with >10% missing data were discarded, and the remainder underwent median imputation. In total, 321 potential predictors were included. Random forest, elastic net regression, and support vector machines (SVMs) with radial and linear kernels were trained. Model performance was evaluated by area under the receiver operating characteristic curve (AUC).
RESULT(S): Of the patients, 69.0% (n=727) and 69.1% (n=311) in the training and testing sets received operative management, respectively. Upon evaluation with the testing dataset, performance for SVM linear (AUC=0.910), elastic net (0.913), and SVM radial (0.914) models was excellent, and the random forest model performed very well (0.830). In our SVM radial model, HRQoL metrics were particularly important for making predictions; the top 3 most important variables were SRS appearance, SRS total, and ODI.
CONCLUSION(S): This study developed models exhibiting excellent discrimination (AUC>0.9) between patients receiving operative vs nonoperative management, based solely on baseline enrollment values. HRQoL metrics were strongest in making these predictions. Future investigations may evaluate the implementation of such models for decision support in the clinical setting. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Antifibrinolytic agents are used during ASD surgery to minimize blood loss and transfusion requirements. Tranexamic acid (TXA) reduces the risk of blood loss and transfusion after ASD surgery, but there persists concern for prothrombotic effects, myocardial infarction, stroke, and postoperative neurologic events including seizures. PURPOSE: To investigate perioperative blood loss and transfusion after TXA for ASD surgery. STUDY DESIGN/SETTING: Retrospective review of prospectively collected single center database. PATIENT SAMPLE: 469 patients who received TXA, and 354 patients who did not receive TXA. OUTCOME MEASURES: Perioperative blood loss and blood product transfusion rate, and complications.
METHOD(S): Using a single-institution multi-surgeon database, we performed a retrospective review of patients undergoing ASD surgery from 2011-2018. We identified 469 patients who received TXA, and 354 patients who did not receive TXA. We investigated perioperative blood loss and blood product transfusion rate, and complications occurring after surgery.
RESULT(S): There was no significant difference in age, BMI, or frailty between the TXA (age: 45 +/- 23, BMI: 25 +/- 6) and non-TXA group (age: 47 +/- 24, BMI: 26 +/- 7). The prevalence of coronary artery disease, chronic kidney disease, and history of pulmonary embolism was higher in the non-TXA group, presumably due to surgeon preoperative screening, with no difference in other medical comorbidities. There were more revision surgeries and pelvic fixation procedures in the TXA group, with no other differences in surgical complexity. The group that received TXA had significantly lower EBL (1693 +/- 1343 mL vs 2009 +/- 1892 mL, p=0.019), and were transfused less platelets intraoperatively (.07 +/-.3 U vs 0.25 +/- 0.86 U, p=0.012). There was no difference in rates of perioperative pRBC transfusion between the groups. The most common complications in both groups were ileus and urinary retention. There was no difference in rate of thrombotic, cardiac, or renal complications, or seizures between the two groups. There was no significant difference in 90-day complication, readmission, or revision rates.
CONCLUSION(S): Among patients undergoing ASD surgery, TXA was associated with a lower estimated blood loss, without a higher risk for any morbid event. To our knowledge, this is the largest study to date to evaluate the safety of TXA for ASD surgery. FDA DEVICE/DRUG STATUS: Unavailable from authors at time of publication.
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BACKGROUND CONTEXT: Bariatric surgery for morbid obesity helps to address common comorbidity burdens, including decreasing rates of myocardial infarction and stroke. The increased mechanical stresses on the spine caused by morbid obesity predispose patients to various spinal pathologies and are concerning for spinal surgeons, with previous studies suggesting poorer outcomes than the general population. The effects of bariatric surgery on diminishing spinal complaints or symptoms have yet to be elucidated in the literature. PURPOSE: To assess the rate in which various spinal symptoms diminish after bariatric surgery. STUDY DESIGN/SETTING: Retrospective analysis of the prospectively collected New York State Inpatient Database (NYSID) years (2004-2013). PATIENT SAMPLE: A total of 4,351 patients who underwent bariatric surgery with at least one identified spinal diagnosis present before bariatric surgery. OUTCOME MEASURES: Time from bariatric surgery until disappearance of specific spinal complaint, percentage of unresolved spinal complaints with 2-year follow-up.
METHOD(S): Retrospective analysis of the prospectively collected (NYSID) years 2004-2013. Patient linkage codes allow identification of multiple and return inpatient stays within the time frame analyzed (720 days). Inclusion criteria were bariatrics surgery patients with one or more visits prior to and after bariatric procedure (excluding pts with <30 days f/u, spine surgery, or new post-bariatric spine pathology) for one of the following common cervical or lumbar spinal diagnoses, queried with ICD-9CM codes: herniation, stenosis, spondylosis, disc degeneration, and spondylolisthesis. Time from bariatric surgery until the patient's respective spinal diagnosis was no longer present was considered resolution of spinal symptoms. Kaplan-Meier survivorship curves assessed rates of resolution within each spinal diagnosis cohort.
RESULT(S): A total of 4,351 bariatric surgery pts with a preop spinal diagnosis by ICD-9 were analyzed. Lumbar pts: 1,049 had stenosis, 774 spondylosis, 648 degeneration, 249 spondylolisthesis, 72 disc herniation. Cervical pts: 581 disc herniation, 376 had stenosis, 366 spondylosis, 236 degeneration. Cumulative resolution rates at 90-day, 180-day, 360-day, and 720-day follow-up were as follows: lumbar stenosis (48%,67.6%,79%,91%), lumbar herniation (61%,77%,86%,93%), lumbar spondylosis (47%,65%,80%,93%), lumbar spondylolisthesis (37%,58%,70%,87%), lumbar degeneration (37%,56%,72%,86%). By cervical region: cervical stenosis (48%,70%,84%,94%), cervical herniation (39%,58%,74%,87%), cervical spondylosis (46%, 70%,83%, 94%), cervical degeneration (44%,64%,78%,89%). Lumbar herniation pts saw significantly higher 90d-resolution than cervical herniation pts (p<0.001). Cervical vs lumbar degeneration resolution rates did not differ @90d (p=0.058), but did @180d(p=0.034). Cervical and lumbar stenosis resolution was similar @90d & 180d, but cervical showed greater resolution by 1 year (p=0.036).
CONCLUSION(S): Over 50% of bariatric patients diagnosed with a cervical or lumbar pathology before weight-loss surgery no longer sought inpatient care for their respective spinal diagnosis by 180 days postop. Lumbar herniation had significantly higher resolution than cervical herniation by 90d, whereas cervical degeneration and stenosis resolved at higher rates than corresponding lumbar pathologies by 180d and 1-year follow-up, respectively. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Cannabis is the most commonly used illicit drug in the United States with 4 million Americans meeting clinical criteria for cannabis dependence or abuse in 2015. With recent state-level legalization efforts and changing public perception, its use is expected to grow. Considering these changes and the reported medicinally beneficial effects, studies evaluating cannabis use and its impact on outcomes following cervical fusion (CF) are quite limited; further detailed study is warranted. PURPOSE: This study sought to identify if adverse outcomes, such as complications, readmissions, and revisions, are comparable between cannabis users and noncannabis users undergoing CF. We compared 90-day complication and readmission rates and 2-year revision rates between baseline cannabis users and nonusers following CF. STUDY DESIGN/SETTING: Retrospective cohort study of a prospectively collected database. PATIENT SAMPLE: All patients who underwent CF between January 2009 and September 2013 in the New York Statewide Planning and Research Cooperative System (SPARCS) were identified. Patients were included if they had <=90-day follow-up for complications and readmissions, or >=2-year follow-up for revisions. Patients with a preoperative ICD-9-CM diagnosis of cannabis abuse (Cannabis) or dependence were identified. Patients were excluded for systemic disease, osteomyelitis, cancer, trauma, or concomitant substance or polysubstance abuse/dependence. OUTCOME MEASURES: Demographic information, fusion approach, fusion levels, complications, readmissions, and revisions.
METHOD(S): All patients aged >=18y who underwent CF from 2009-13 were identified via the SPARCS database and included if they had <=90D follow-up for complications and readmissions or 2Y follow-up for revisions. Pts with preoperative cannabis abuse/dependence identified (Cannabis). Pts were excluded for systemic disease, osteomyelitis, cancer, trauma, or concomitant substance or polysubstance abuse/dependence. Following patient selection in the SPARCS database, Cannabis patients were 1:1 propensity score-matched by age, gender, race, Deyo score, fusion levels and approach, and tobacco use to nonusers (Non-Cannabis). These groups were compared for hospital-related parameters, rates of 90-day complications and readmissions, and 2-year revisions. Multivariate binary stepwise logistic regression models identified independent predictors of these outcomes.
RESULT(S): A total of 432 pts (n=216 each) were identified, with comparable age, sex, Deyo scores, tobacco use rates, and distribution of anterior or posterior approach (all p>0.05). Cannabis patients were more frequently African American (27.8% vs 12.0%), primarily utilized Medicaid (29.6% vs 12.5%), and incurred longer lengths of stay (3.0 vs 1.9 days), all p<=0.001. Both cohorts experienced comparable rates of 90-day medical, surgical and overall complications (5.6% vs 3.7%) and 2-year revisions (4.3% vs 2.8%), p<=0.430. Cannabis users experienced higher 90-day readmission rates (11.6% vs 6.0%, p=0.042). Cannabis use was an independent predictive factor of 90-day readmission (OR=2.0, 95%CI, 1.0-4.1, p=0.049), but did not predict any 90-day complications or 2-year revisions (all p>0.05).
CONCLUSION(S): Baseline cannabis dependence/abuse was associated with increased 90-day readmission odds following CF. Further investigation of the physiologic impact of cannabis on musculoskeletal patients may identify what measurable or overlooked patient factors contribute to this association. FDA DEVICE/DRUG STATUS: Unavailable from authors at time of publication.
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BACKGROUND CONTEXT: Lateral interbody fusion (LLIF) is often performed with biologic adjuvants to promote fusion. Commercially available bone allograft containing allogeneic stem cells (ASC) and bone morphogenetic protein-2 (BMP) are designed to promote fusion while avoiding the morbidity of iliac crest autograft; however, no study to date has directly compared the two in LLIF. The ASC studied is Osteocel Pro (NuVasive, Inc). PURPOSE: This non-industry funded study compares fusion rate, complications, and costs between LLIF with BMP and ASC. STUDY DESIGN/SETTING: Single center retrospective comparative study. PATIENT SAMPLE: Patients with 1-3 lumbar levels treated with LLIF. OUTCOME MEASURES: Outcomes measures are fusion at 1 year postoperative, complication rates, length of stay, and costs.
METHOD(S): A retrospective chart review was conducted to identify patients treated with LLIF and ASC or BMP from February 2012 through September 2017. Patients were included who had from 1-3 lumbar levels treated with LLIF and at least 1 year of radiographic follow up. Interbody fusion was assessed on lumbar X-ray images using a validated scale.
RESULT(S): A total of 94 patients were included representing 162 levels fused. Of these, 74 patients and 133 levels were treated with BMP; 20 patients and 29 levels were treated with ASC. Comparing patients treated with BMP or ASC, there were no differences in age [61.6 vs 60.4, p=0.7], BMI [29.8 vs 28.3, p=0.3], gender [60.8% vs 55.0% female], smoking status [12.2% vs 10.0%, p=1], diabetes [28.4% vs 15.0%, p=0.2], Charleston Comorbidity Index [4.3 vs 3.5, p=0.2], revision status [47.3% vs 45.0%, p=0.9], intraoperative complications [4.1% vs 5.0%, p=1], postoperative complications [37.8% vs 30.0%, p=0.5], or blood loss [881 vs 528ml, p=0.2]. More levels were fused in the BMP group (1.8 vs 1.45, p=0.04) and the BMP group tended toward a longer length of stay [4.8 vs 3.8 days, p=0.06]. There was a nonsignificant trend toward a higher fusion rate with BMP vs ASC[98.5% vs 93.1%, p=0.1]. The average amount of rhBMP used per level was 2.0 cc compared to 5.9 cc of ASC. There was no difference in the cost of the BMP per level compared with ASC [4.45% vs 4.80%, p=0.33], but the BMP group tended toward a higher cost of total care [103.5% vs 87.6%, p=0.1].
CONCLUSION(S): ASC and BMP are both acceptable adjuvants in LLIF that demonstrate comparable fusion rates at 1 year with comparable cost in the setting of similar groups of patients. The radiographic fusion rate seen in our study compares to previous reports in the literature using ASC. Cost considerations are becoming ever more cogent in spine surgery; the results of this study can inform decision making regarding which biologic adjuvant to use in lumbar interbody fusion. FDA DEVICE/DRUG STATUS: Osteocel (Approved for this indication), rhBMP (Infuse) (Not approved for this indication)
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