Faculty Bibliography

BACKGROUND CONTEXT: Surgical intervention of the cervical spine is a challenging procedure that can present postoperative complications such as dysphagia, swelling, and reoperations. However, the risk of reoperation can possibly be mitigated with the use of biologics to enhance fusion. There is paucity in the literature on long-term incidence of reoperations after application of BMP during ACDF. PURPOSE: To evaluate if bone morphogenetic protein usage during anterior cervical discectomy and fusion will decrease reoperation rates. STUDY DESIGN/SETTING: Retrospective review of the PearlDiver database between 2006-2014. PATIENT SAMPLE: Matched cohort of 35,544 ACDF patients. OUTCOME MEASURES: Reoperations.
METHOD(S): Patients undergoing an anterior cervical discectomy and fusion between the years 2006-2014 were isolated in the PearlDiver database. Patients receiving BMP operatively and a control with no BMP were matched for baseline demographics including age, sex, and comorbidities. A Kaplan Meier Survival analysis assessed five-Year Reoperation-Free Survival between BMP patients and controls. Statistical significance was set to p<0.05.
RESULT(S): A matched cohort of 35,544 ACDF patients was isolated. A total of 17,772 patients received BMP while undergoing cervical fusion and 17,772 did not receive any BMP during surgery. Patients did not differ in age, sex or comorbidities (p>0.05). Kaplan Meier survival analysis showed patients receiving BMP during cervical fusion were significantly more likely to remain reoperation free five years after index surgery (p<0.05). Overall, 91.3% of BMP patients remained reoperation free at five years.
CONCLUSION(S): For patients receiving bone morphogenetic protein during anterior cervical discectomy and fusion, Kaplan-Meier survival analysis following five years post index surgery had showed a 91.3% reoperation-free survivorship. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: For patients with coronary artery disease, the two most common options for intervention are a cardiac stent or a coronary artery bypass graft. Although less invasive, stents may pose a long-term risk for patients undergoing further invasive procedures such as elective spine surgery. This study aimed to provide surgeons with insight on possible major complications for elective spine surgery patients with a history of coronary artery disease. PURPOSE: Investigate outcomes of elective spine fusion patients with prior history of cardiac intervention STUDY DESIGN/SETTING: Retrospective review of the PearlDiver database between the years 2006-2013 PATIENT SAMPLE: A total of 731,173 elective spine fusion patients OUTCOME MEASURES: Comorbidity burden, 30-day and 90-day complications, readmission METHODS: Elective spine fusion patients were isolated with ICD-9 and CPT procedures codes in the PearlDiver database. Patients were stratified by having previous history of a coronary stent (Stent), coronary artery bypass graft (CABG), and no previous heart procedure (No-HP). Means comparison tests (chi-squared and independent samples t-tests, as appropriate) compared differences in demographics, diagnoses, and comorbidities. Logistic regression assessed the odds of 30-day and 90-day postoperative (postop) complications associated with each heart procedure (Odds Ratio [95% confidence interval]). Statistical significance was set p<0.05.
RESULT(S): A total of 731,173 elective spine fusion patients were included. Overall, 8,401 pts underwent a CABG, 24,037 patients Stent, and 698,735 had No-HP prior to spine fusion surgery. Compared to Stent and No-HP patients, CABG patients had higher rates of morbid obesity, chronic kidney disease and diabetes (p<0.001 for all). Stent patients had higher rates of peripheral vascular disease, hypertension, and hyperlipidemia (all p<0.001). Within 30 days postoperatively of index surgery, CABG patients had significantly higher complication rates including pneumonia, cerebrovascular accident (CVA), myocardial infarction (MI), sepsis, and death compared to No-HP (all p<0.001). Stent patients vs No-HF also had higher 30-day postoperative complication rates including pneumonia, CVA, MI, sepsis, and death. Adjusting for age, comorbidities and sex, Stent was significantly predictive of a MI 30-days post-op (OR: 1.90 [1.53-2.34], P<0.001). Additionally, Stent patients compared to CABG patients had 1.99x greater odds of a MI within 30-days (OR: 1.99 [1.26-3.31], p=0.005) and 2.02x greater odds of readmission within 90-days postop (OR: 2.2 [1.53-2.71, p<0.001).
CONCLUSION(S): With regards to spine surgery, coronary artery bypass graft remains the gold standard for risk reduction. Stenting does not appear to minimize risk as significantly as CABG. When assessing patients with a history of coronary artery disease for elective spine fusion surgery, surgeons should be cautious of the significant risk of major complications associated with stents compared to coronary artery bypass grafting. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: With a heightened focus on prescription narcotic use in the United States, concern among surgeons has increased regarding preoperative and postoperative usage. However, the literature is scarce on outcomes of preoperative and prolonged opioid usage in adult spinal deformity (ASD) patients. PURPOSE: Investigate effect of preoperative opioid usage on prolonged opioid use postoperatively and rates of reoperations. STUDY DESIGN/SETTING: Retrospective review of the PearlDiver Database 2008-2013. PATIENT SAMPLE: A total of 7,661 ASD patients. OUTCOME MEASURES: Reoperations, 90-day complications, comorbidity burden, prolonged opioid usage METHODS: ASD patients undergoing a fusion were isolated in the PearlDiver database between the years 2008-2013 using ICD-9 and CPT codes. Patients were stratified by prescription preoperative opioid use 3 months prior to surgery: (1) high frequency (>4 refills); (2) low frequency (1-3 refills); (3) opioid naive. Means comparison tests compared differences in demographics, complications, and reoperation rates. Logistic regression assessed the odds of complication and reoperations associated with preoperative frequency and prolonged opioid use (3 to 6 months postop), controlling for age, sex, and comorbidities.
RESULT(S): A total of 7,661 ASD patients were isolated; 2,342 patients were high frequency preop opioid users, 2,247 low frequency preop opioid users, and 3,072 opioid naive. At BL, high frequency preop opioid users had higher rates of obesity, diabetes mellitus, CHF, COPD, hypertension, smoking and alcohol use (all p<0.001). Compared to opioid naive patients, low frequency preop opioid users had higher rates of 90-day complications associated with hematoma and transfusion (p<0.05). High frequency preop opioid users relative to naive opioid users had significantly increased 90-day complication rates including pulmonary embolism, pneumonia, hematoma, and transfusions. High frequency opioid use was associated with increased odds of wound disruption (1.74[1.22-2.51]) and hospital readmission (1.42[1.22-1.64], both p<0.05). Additionally, high frequency opioid usage preop followed by prolonged opioid use postop was associated with increased odds of reoperations at 2Y relative to low frequency (1.67[1.34-2.10]) and opioid naive patients (1.83[1.40-2.42], both p<0.001).
CONCLUSION(S): Patients with high frequency preoperative opioid use are at increased risk of major complications within 90 days of surgery, prolonged use postoperatively, and increased risk of reoperations within two years. During preoperative risk assessment, providers should consider the effect of pre- and postoperative opioid usage on patient outcomes. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: MBDs are often implicated in or contribute to degenerative disc disease (DDD). Yet, there is limited long-term, postoperative outcome data on the impact of MBDs on 2-year outcomes following 2-3-level lumbar fusion for DDD. PURPOSE: To determine if DDD patients with MBDs have comparable outcomes to those without MBDs following lumbar fusion. STUDY DESIGN/SETTING: Retrospective cohort. PATIENT SAMPLE: New York State Statewide Planning and Research Cooperative System was reviewed from 2009-2013 to identify all patients with DDD who underwent short, lumbar fusion (2-3-levels) with >=2-year follow-up OUTCOME MEASURES: Two-year outcome rates (medical/surgical complications and reoperations).
METHOD(S): The New York State Statewide Planning and Research Cooperative System was reviewed from 2009-2013 to identify all patients with DDD who underwent short, lumbar fusion (2-3 levels) with >=2-year follow-up. Patients with and without MBD (vitamin D deficiency, hyperparathyroidism, osteomalacia, and rickets) were identified. Any patients with osteoporosis or other systemic/endocrine disorders affecting bone quality were excluded. Traumatic, infectious, and neoplastic surgical indications were excluded. Cohorts were compared for demographics and 2-year outcome rates (medical/surgical complications and reoperations). Logistic regression was used to identify covariates associated with medical/surgical complications and revisions.
RESULT(S): A total of 28,959 patients were included (MBD, n=380 (1.33%); no-MBD, n=28,579). MBD pts were older (56.4 vs 53.1 years) and more often female (65.5% vs 49.80%) than no-MBD pts (all p<0.001). MBD pts had longer hospital stays (4.57 days vs 4.11 days, p=0.026), but charges were similar. MBD pts incurred higher rates of wound complications (11.8% vs 6.0%), acute renal failure (11.1% vs 4.7%), pneumonia (9.2% vs 4.4%), and implant related complications (12.1% vs 7.0%); all p<0.001. Rates of pseudarthrosis, PE, pulmonary complications, and UTI were similar between groups. MBDs were associated with developing both medical complications (OR=1.55) and surgical complications (OR=1.79), both p<0.001.
CONCLUSION(S): MBD patients have an increased risk of 2-year postop comps and reoperations following short lumbar fusion for DDD compared to patients without MBD when controlling for demographics and comorbidity profile. These data underscore the importance of preoperative screening and optimization in this patient population. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: The impact of neuromuscular disorders such as multiple sclerosis (MS) on outcomes following anterior cervical discectomy and fusion (ACDF) is underreported. PURPOSE: Identify the impact of MS on two-year (2Y) postoperative complications and revisions following 2-3-level ACDF for cervical radiculopathy (CR) or myelopathy (CM). STUDY DESIGN/SETTING: Retrospective review of the New York State Statewide Planning and Research Cooperative System (SPARCS) database. PATIENT SAMPLE: Patients undergoing 2-3 level ACDF for CR/CM. OUTCOME MEASURES: Two-year postoperative complications and reoperations.
METHOD(S): Patients undergoing 2-3 level ACDF for CR/CM were identified from SPARCS. Patients with a baseline diagnosis of MS were also identified. Patients with infectious/traumatic/neoplastic were excluded. The remaining patients were 1:1 propensity score-matched (MS to no-MS) for age, sex, race, Deyo index and compared for rates of 2Y postoperative complications and reoperations. Logistic regression models were utilized to determine significant predictors of these outcomes.
RESULT(S): A total of 302 total patients were identified (MS, n=151; non-MS, n=151). MS patients were more frequently female (72.8% vs 27.2%, p<0.001). Age was comparable (50.1 vs 50.1 years, p=0.225). MS patients incurred higher charges for their surgical visit ($41,029 vs $31,654) and higher LOS (2.8 vs 2.2 days), both p<=0.016. They experienced higher rates of deep vein thrombosis (DVT) (3.3% vs 0%, p=0.02), with similar overall medical (19.2% vs 21.2%), surgical (7.9% vs 10.6%), and total complications (21.9% vs 25.8%), all p>0.05. MS patients had similar rates of 2Y revisions (6.6% vs 5.3%, p=0.627). MS was not associated with medical, surgical, or overall complications or revisions at minimum 2Y follow-up.
CONCLUSION(S): Despite differences in demographics and higher rates of postoperative DVT, MS patients experienced comparable postoperative course with respect to other individual and overall complications and revisions following 2-3-level CF for degenerative spinal pathologies. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Hospital acquired conditions (HACs) were established in the Affordable Care Act, and are defined as reasonably preventable complications that are nonreimbursable. In high risk patient populations for HACs, such as frail surgical spine patients, preoperative evaluation should consider modifiable factors. PURPOSE: To identify if optimizing the modifiable factors in the frailty index reduce the risk of developing HACs in population of surgical spine patients. STUDY DESIGN/SETTING: Retrospective cohort study. PATIENT SAMPLE: This study included 196,523 elective spine surgery patients in the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP). OUTCOME MEASURES: Modifiable patient frailty factors: hypertension and diabetes mellitus; rates of HACs, superficial or deep surgical site infection (SSI), deep venous thromboembolism (VTE) and urinary tract infection (UTI), across frailty scores.
METHOD(S): Patients >18 years who underwent elective spine surgery were identified in ACS-NSQIP database from 2005-2016. HACs identified: SSI, VTE, and UTI. Patient frailty was assessed utilizing the modified NSQIP 5-factor frailty index. The modified frailty score (mFI-5) is assessed on a scale between 0 and 1 (no frailty [NF] <0.3, mild frailty [MF] 0.3-0.5, severe frailty [SF] >0.5). Descriptive analysis quantified rates of patient characteristics, operative details, and HAC prevalence. Stepwise linear regression models determined significant predictors of baseline frailty using controllable patient factors. HACs were compared between 'optimized' and 'non-optimized' frailty status in the cohort. Level of significance was set to P<0.05.
RESULT(S): A total of 196,523 patients (57+/-14.2 years, 30.4 kg/m², 48%F) met inclusion criteria. Overall, 5,720 (2.9%) of patients developed an HAC, the most common was an SSI (1.3%), followed by UTI (1.1%). When stratified by the mFI-5 frailty severity groups at baseline, 83.6% of patients were categorized NF, 15.1% MF and 1.3% SF. Within the frailty severity groups, prevalence of overall HACs increased significantly (NF: 2.64%, MF: 4.17%, 5.93%, p<0.001). Rates of all individual postoperative HACs assessed also increased with greater baseline frailty severity: SSI (NF: 1.14%, MF: 1.93%, SF: 2.39%, p<0.001), UTI (NF: 0.91%, MF: 1.66%, SF: 2.85%, p<0.001), VTE (NF: 0.68%, MF: 0.80%, SF: 1.16%, p=0.002). Stepwise linear regression models determined that diabetes mellitus (beta = 0.493) and hypertension (beta = 0.679) were the most significant predictors for increased baseline frailty by way of the mFI-5 NSQIP index (Final model: R2= 0.897). Of total patients, 47.2% had the optimal modifiable frailty factors (no history of diabetes or hypertension). The optimal frailty patients had significantly less overall incidence of SSI (2.03% vs 2.5%, p<0.001), UTI (0.65% vs 1.4%, p<0.001), DVT (0.56% vs 0.84%, p<0.001), and any overall HAC (2.18% vs 3.56%, p<0.001).
CONCLUSION(S): Stepwise linear regression models determined that hypertension and diabetes account for 89.7% of variance in baseline mFI-5 score. Patients with these optimal controllable factors had reduced incidence of all hospital acquired conditions. In order to optimize hospital resources and treatment outcomes, physicians and patients should be aware of the modifiable factors that contribute to a patient's frailty that can ultimately impact acquiring HACs. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Vascular stenting is a common intervention for patients afflicted with coronary artery disease. For elective spine fusion patients with a history of coronary artery disease, a stent provides a less invasive surgical intervention allowing patients to move forward with spinal surgery. However, the impact of an initially less invasive cardiac intervention on outcomes of future surgical spine procedures has been understudied. PURPOSE: Investigate effect of coronary stents on postoperative outcomes in an elective spine fusion cohort. STUDY DESIGN/SETTING: Retrospective review of the PearlDiver database between the years 2006-2013. PATIENT SAMPLE: A total of 726,061 elective spine fusion patients. OUTCOME MEASURES: Comorbidity burden, 30-day and 90-day complications (myocardial infarction, pneumonia, sepsis, death, would complications, transfusions), length of stay.
METHOD(S): Elective spine fusion patients were isolated with ICD-9 and CPT procedures codes in the PearlDiver database. Patients were stratified by number of coronary stents: (1) 1-2 stents (ST12); (2) 3-4 stents (ST34); (3) no stents. Means comparison tests compared differences in demographics, diagnoses, comorbidities, 30-day and 90-day complication outcomes. Logistic regression assessed the odds of complication associated with coronary stents, controlling for levels fused, age, sex, and comorbidities (odds ratio [95% confidence interval]). Statistical significance was set p<0.05.
RESULT(S): A total of 726,061 elective spine fusion patients were isolated; 707,396 patients had no stent, 17,087 ST12 and 1,578 ST34. At BL, ST12 patients had higher rates of morbid obesity, chronic kidney disease, CHF, COPD, and diabetes mellitus compared to no stent and ST34 (all p<0.001). Relative to no stent patients, ST12 patients had a greater LOS and at 30 days, significantly higher complication rates including pneumonia, myocardial infarction, sepsis, AKI, UTI, wound complications, transfusions, and 30-day readmission (p<0.05). Controlling for age, sex, comorbidities, and levels fused ST12 was a significant predictor of MI within 30 days (OR: 2.15[1.7-2.7], p<0.001) and 90-days postop (OR:1.87[1.6-2.2], p<0.001). ST34 patients compared to no stent at 30 days presented with increased complication rates such as pneumonia, MI, sepsis, UTI, wound complications, and 30-day readmissions. Regression analysis show no significant differences in complications between ST12 vs ST34 at 30 days, but at 90 days ST34 was associated with significantly increased rate and odds of death (1.1% vs 0.3%, p=0.021; OR:1.94 [1.13-3.13],p=0.01).
CONCLUSION(S): Cardiac stents failed to normalize risk profile of patients with coronary artery disease. Postoperatively at 90 days, elective spine fusion patients with 3 or more stents were significantly at risk of mortality compared to patients with fewer or no stents. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND:Little is known of how frailty, a dynamic measure of physiological age, progresses relative to age or disability status. Operative treatment of adult spinal deformity (ASD) may play a role in frailty remediation and maintenance. PURPOSE/OBJECTIVE:Compare frailty status, severe frailty development, and factors influencing severe frailty development among ASD patients undergoing operative or non-operative treatment. DESIGN/METHODS:Retrospective review with maximum follow up of 3 years. SETTING/METHODS:Prospective, multicenter, ASD database. PARTICIPANTS/METHODS:Patients were consecutively enrolled from 13 participating centers. INCLUSION CRITERIA/METHODS:≥18 years undergoing either operative or non-operative treatment for ASD, exclusion criteria: spinal deformity of neuromuscular etiology, presence of active infection, or malignancy. The mean age of the participants analyzed were 54.9 for the operative cohort and 55.0 for the non-operative cohort. MAIN OUTCOMES/RESULTS:Frailty status, severe frailty development and factors influencing severe frailty development. METHODS:ASD patients (coronal scoliosis≥20°, sagittal vertical axis (SVA)≥5cm, Pelvic Tilt (PT)≥25°, or thoracic kyphosis≥60°) >18y/o, with Base Line (BL) frailty scores were included. Frailty was scored from 0-1 (not frail: <0.3, frail 0.3-0.5, severe frailty >0.5) through the use of ASD-FI which has been validated using the International Spine Study Group (ISSG) ASD database, European Spine Study Group (ESSG) ASD database, and the Scoli-RISK-1 Patient Database. The International Spine Study Group (ISSG) is funded through research grants from DePuy Synthes and individual donations, and supported the current work. Operative (Op) and Non-Operative (Non-Op) patients were propensity matched. T-tests compared frailty among treatment groups and BL, 1Y, 2Y, and ≥3Y. An actuarial Kaplan-Meier survivorship analysis with Log Rank (Mantel-Cox) test, adjusting for patients lost to follow-up, determined probability of severe frailty development. Multivariate Cox Regressions gauged the effect of sagittal malalignment, patient and surgical details on severe frailty development. RESULTS:The analysis includes 472 patients (236 Op, 236 Non-Op) selected by propensity score matching from a cohort of 1172. Demographics and comorbidities were similar between groups (p>0.05). Op exhibited decreased frailty at all follow up intervals compared to BL (BL:0.22 vs Y1:0.18; Y2:0.16; Y3:0.15, all p<0.001). Non-Op displayed similar frailty from BL to 2Y follow up, and increased frailty at 3Y follow up (0.23 vs 0.25, p=0.014). Compared to Non-Op, Op had lower frailty at 1Y (0.18 vs 0.24), 2Y (0.16 vs 0.23) and 3Y (0.15 vs 0.25) (all p<0.001). Cumulative probability of maintaining non-severe frailty was (Op:97.7%, Non-Op:94.5%) at 1Y, (Op:95.1%, Non-Op:90.4%) at 2Y, and (Op:95.1%, Non-Op:89.1%) at ≥3Y, (p=0.018). Amongst all patients, baseline depression (HR: 2.688[1.172-6.167], p=0.020), NRS back pain scores (HR: 1.247[1.012-1.537], p=0.039), and non-operative treatment (HR: 2.785[1.167-6.659], p=0.021) predicted severe frailty development with having a HR>1.0 and p-value<0.05. Among operative patients, 6-week postoperative residual SVA malalignment (SRS-Schwab SVA + modifier) (HR: 15.034[1.922-116.940], p=0.010) predicted severe frailty development indicated by having a HR>1.0 and p-value <0.05. CONCLUSIONS:Non-Op patients were more likely to develop severe frailty, and at a quicker rate. Baseline depression, increased NRS back pain scores, non-operative treatment, and postoperative sagittal malalignment at 6-week follow-up significantly predicted severe frailty development. Operative intervention and postoperative sagittal balance appear to play significant roles in frailty remediation and maintenance in adult spinal deformity patients. Frailty is one factor, in a multifactorial conservation, that may be considered when determining operative or non-operative values for ASD patients. Operating before the onset of severe frailty, may result in a lower complication risk and better long term clinical outcomes. LEVEL OF EVIDENCE/METHODS:III.

There has been limited discussion as to whether spine surgery patients are benefiting from shorter in-patient hospital stays or if they are incurring higher rates of readmission and complications secondary to shortened length of stays. Included in this study were 237,446 spine patients >18yrs and excluding infection. Patients with Clavien Grade 5 complications in 2015 had the lowest mean time to readmission after initial surgery in all years at 12.44 ± 9.03 days. Pearson bivariate correlations between LOS ≤ 1 day and decreasing days to readmission was the strongest in 2016.). Logistic regression analysis found that LOS ≤ 1 day showed an overall increase in the odds of hospital readmission from 2012 to 2016 (2.29 [2.00-2.63], 2.33 [2.08-2.61], 2.35 [2.11-2.61], 2.27 [2.06-2.49], 2.33 [2.14-2.54], all p < 0.001).

STUDY DESIGN/UNASSIGNED:Retrospective cohort study of prospective patients undergoing minimally invasive lumbar fusion at a single academic institution. OBJECTIVE/UNASSIGNED:To assess differences in perioperative outcomes between primary and revision MIS (minimally invasive surgical) lumbar interbody fusion patients and compare with those undergoing corresponding open procedures. METHODS/UNASSIGNED:Patients ≥18 years old undergoing lumbar interbody fusion were grouped by surgical technique: MIS or open. Patients within each group were propensity score matched for comorbidities and levels fused. Patient demographics, surgical factors, and perioperative complication incidences were compared between primary and revision cases using means comparison tests, as appropriate. RESULTS/UNASSIGNED:< .05). CONCLUSIONS/UNASSIGNED:Clinical outcomes of revision MIS lumbar interbody fusion were similar to those of primary surgery. Additionally, MIS techniques were associated with less EBL, shorter LOS, and fewer perioperative complications than corresponding open revisions.