Advances in the Endovascular Management of Cerebrovascular Disease.

The field of endovascular neurosurgery has experienced remarkable progress over the last few decades. Endovascular treatments have continued to gain traction as the advancement of technology, technique, and procedural safety has allowed for the expansion of treatment indications of various cerebrovascular pathologies. Interventions such as the coiling of intracranial aneurysms, carotid artery stenting, mechanical thrombectomy in the setting of ischemic stroke, and endovascular embolization of arteriovenous malformations have all seen transformations in their safety and efficacy, expanding the scope of endovascularly treatable conditions and offering new hope to patients who may have otherwise not been candidates for surgical intervention. Despite this notable progress, challenges persist, including complications associated with device deployment and questions regarding long-term outcomes. This article explores the advancements in endovascular neurosurgical techniques, highlighting the impact on patient care, outcomes, and the evolution of traditional surgical methods.

Cutting Edge Developments in Spine Surgery at the University of Missouri.

The treatment of spinal pathologies has evolved significantly from the times of Hippocrates and Galen to the current era. This evolution has led to the development of cutting-edge technologies to improve surgical techniques and patient outcomes. The University of Missouri Health System is a high-volume, tertiary care academic medical center that serves a large catchment area in central Missouri and beyond. The Department of Neurosurgery has sought to integrate the best available technologies to serve their spine patients. These technological advancements include intra-operative image guidance, robotic spine surgery, minimally invasive techniques, motion preservation surgery, and interdisciplinary care of metastatic disease to the spine. These advances have resulted in safer surgeries with enhanced outcomes at the University of Missouri. This integration of innovation demonstrates our tireless commitment to ensuring excellence in the comprehensive care of a diverse range of patients with complex spinal pathologies.

COVID-19 Vaccine Related Cervical Radiculitis and Parsonage-Turner Syndrome: Case Report and Review of the Literature.

Parsonage-Turner Syndrome, or neuralgic amyotrophy, is an acute-onset upper limb and shoulder girdle palsy that can occur in a post-viral, post-surgical or idiopathic setting. There have also been some reported cases of the syndrome occurring following vaccinations. The pathophysiology of neuralgic amyotrophy is not completely understood and many of the commonly used diagnostic imaging modalities we use to try and diagnose this syndrome are inaccurate and misleading. We present the case of a 40-year-old gentleman who presented with acute onset burning pain and fasciculations in his right upper extremity following vaccination with the second dose of the Pfizer-BioNTech COVID-19 vaccine. His symptoms progressed to weakness in isolated muscle groups with electromyographic evidence of decreased nerve conduction. MRI of the cervical spine demonstrated multilevel central and foraminal stenosis, suggesting a diagnosis of cervical radiculopathy. The patient underwent a C4-5/C5-6 and C6-7 laminoforaminotomy and tolerated the procedure well. Post-operatively, the patient has experienced gradual symptom improvement with residual right triceps and pectoralis muscle weakness as well as paresthesias of the right elbow and forearm. Parsonage-Turner Syndrome is a brachial plexus palsy that can affect one or multiple branches of the brachial plexus. It causes acute-onset pain and weakness, and the diagnosis can be difficult to make with the commonly used diagnostic imaging methods. We reviewed other case reports about neuralgic amyotrophy following vaccinations as well as the current literature on more accurate diagnostic imaging modalities that may help our diagnosis and understanding of the pathophysiology of this condition.

Impact of post-procedure stenosis on outcomes of patients with severe intracranial stenosis treated with intracranial stent placement.

BACKGROUND: The optimal target post-procedure stenosis after percutaneous angioplasty and stent placement (PTAS) for intracranial stenosis is unknown. We determined the effect of post-procedure stenosis after intracranial PTAS on subsequent clinical events in patients with severe symptomatic intracranial stenosis. METHODS: We categorized the severity of post-procedure stenosis as '<30%', '30-49%', and '≥50%' among 207 patients who underwent PTAS in a multicenter randomized clinical trial. Outcomes included stroke or death within 72 hours and within 30 days, ipsilateral stroke beyond 30 days of treatment, and stroke or death within 30 days or stroke in the qualifying artery beyond 30 days (primary endpoint of the trial). Cox proportional hazards analysis was performed with adjustments for age, initial severity of stenosis, location of stenosis, and qualifying event. Kaplan-Meier curves were generated for the primary endpoint stratified by post-procedure stenosis with log-rank analysis. RESULTS: The severity of post-procedure stenosis was categorized as <30%, 30-49%, and ≥50% in 112, 73, and 22 patients, respectively. Compared with patients with post-procedure stenosis <30%, there was no difference in the risk of primary endpoint among patients with post-procedure stenoses of 30-49% (hazards ratio (HR) 0.85, 95% confidence interval (95% CI) 0.64 to 1.15) or those with ≥50% (HR 0.91, 95% CI 0.57 to 1.43). Log-rank analysis did not demonstrate a difference in rates of primary endpoint between groups stratified by post-procedure stenosis (P=0.70). CONCLUSION: In the absence of any benefit on short- and long-term outcomes, strategies to achieve a low severity of post-procedure stenosis among patients with severe intracranial stenosis may not be warranted.

Future of Endovascular and Surgical Treatments of Atherosclerotic Intracranial Stenosis.

Intracranial atherosclerotic disease and resultant intracranial stenosis is a global leading cause of stroke, and poses an ongoing treatment challenge. Among patients with intracranial stenosis, those with hemodynamic compromise are at high risk for recurrent stroke despite medical therapy and risk factor modification. Revascularization of the hypoperfused territory is the most plausible treatment strategy for these high-risk patients, yet surgical and endovascular therapies have not yet shown to be sufficiently safe and effective in randomized controlled trials. Advances in diagnostic and therapeutic technologies have led to a resurgence of interest in surgical and endovascular treatment strategies, with a growing body of evidence to support their further evaluation in the treatment of select patient populations. This review outlines the current and emerging endovascular and surgical treatments and highlights promising future management strategies.

Intra-arterial thrombolysis with tenecteplase for the treatment of cervical spinal cord ischemia: Technical case report.

BACKGROUND: In recent years, there have anecdotal reports of intra-arterial thrombolysis (IAT) for the treatment of spinal cord ischemia (SCI) with encouraging results. We describe a patient with acute cervical SCI who underwent IAT with Tenecteplase at our institution. CASE PRESENTATION: A 20-year-old man presented to the emergency department with a 12-hour history of progressive onset upper and lower extremity numbness, weakness, and urinary incontinence after sustaining a fall. MRI of cervical spine demonstrated T2 and STIR hyperintensity in the ventral aspect of the spinal cord spanning the C3, C4, and C5 levels suggestive of SCI. He demonstrated progression of neurologic deficits to C4 ASIA B spinal cord injury with complete loss of motor function, diminished sensation, and absent rectal tone. Emergent angiography was performed with prominent anterior spinal supply via the left ascending cervical artery. A total of 30 mg of Tenecteplase was administered intra-arterially in the bilateral vertebral arteries, bilateral ascending cervical arteries, and bilateral inferior thyroid arteries. Two-week post-intervention neurologic examination demonstrated improvement in injury level and severity. The patient was C6 ASIA C SCI, with 2/5 strength in the distal upper and lower extremities and improved sensation. CONCLUSION: IAT with Tenecteplase may be a feasible option for the treatment of acute spinal cord ischemia in carefully selected patients.

Risk of new cerebral ischemic events in patients with symptomatic internal carotid artery stenosis while awaiting carotid stent placement.

BACKGROUND AND PURPOSE: Although there is an emphasis on performing carotid artery stent (CAS) placement within 2 weeks after index event of transient ischemic attack (TIA) or minor stroke in patients with significant extracranial internal carotid artery (ICA) stenosis, the risks and characteristics of recurrent cerebral ischemic event while waiting for CAS placement are not well defined. METHOD: We analyzed patients admitted to our institution over a 45-month period with symptomatic extracranial ICA stenosis. We identified any new cerebral ischemic events that occurred between index cerebral or retinal ischemic event and CAS placement and categorized them as TIA and minor or major ischemic strokes. We calculated the risk of new ipsilateral cerebral ischemic events between index cerebral or retinal ischemic event and CAS placement. RESULTS: The mean age of 131 patients analyzed was 67 years (range: 47-94 years; 92 were men), and 94 and 37 patients had 70%-99% and 50%-69% severity of stenosis, respectively. The mean and median time intervals between index cerebral or retinal ischemic event and CAS performance were 28 (standard deviation [SD] 30) and 7 (interquartile range 33) days, respectively. A total of 9 of 131 patients (6.9%, 95% confidence interval 2.5%-11.2%) experienced new cerebral ischemic events over 3637 patient days of observation. The risk of new ipsilateral cerebral ischemic events was 2.5 per 1000 patient days of observation. CONCLUSION: We estimated the risk of new ipsilateral cerebral ischemic events in patients with ICA stenosis ≥50% in severity while waiting for CAS placement to guide appropriate timing of procedure.

101 30-Day Outcomes of Resolute Onyx Stent for Symptomatic Intracranial Stenosis: A Multicenter Propensity-Score Matched Comparison With SAMMPRIS Trial.

INTRODUCTION: Symptomatic intracranial atherosclerotic disease (sICAD) is estimated to cause over 10% of strokes annually in the US alone. Previous investigations employing stenting, most notably SAMMPRIS trial, have produced unfavorable results in regards to both periprocedural complications and risk of recurrent stroke. However, newer generation balloon-mounted drug-eluting stents (BM-DES) have been hypothesized to harbor several technical advantages that may confer improvements in these critical metrics. METHODS: Prospectively maintained databases from eight comprehensive stroke centers were reviewed to identify adult patients undergoing RO-ZES for the treatment of sICAD between January,2019 and December,2021. Only patients that presented with either recurrent stroke or TIA, intracranial stenosis 70-99%, with at least one stroke on best medical management were included. The primary outcome was 30-days composite of stroke, ICH, and/or mortality. A propensity-score matched analyses was performed comparing the results of RO-ZES to the intervention arm of SAMMPRIS. RESULTS: A total of 132 patients met the inclusion criteria for analysis (mean age:64.2 years). Mean severity of stenosis (±SD) was 81.4% (±11.4%). Four (3.03%) stroke and/or deaths were reported within 30 days in RO-ZES group. A propensity-score matched analysis based on age, HLD, HTN, DMII, and smoking demonstrated a statistically significant decreased risk of 30-day stroke and/or death rate in RO-ZES in comparison to SAMMPRIS (2.6% vs. 15.6%, respectively; OR 6.88, 95% CI 1.92-37.54, p < 0.001). CONCLUSIONS: Patients treated with RO-ZES had a decreased rate of 30-day major complications in comparison to SAMMPRIS. Further large-scale prospective studies are warranted to evaluate the safety and efficacy of RO-ZES for the treatment of sICAD.

The Impact of Asymptomatic Human Immunodeficiency Virus-Positive Disease Status on Inpatient Complications Following Spine Surgery: A Propensity Score-Matched Analysis.

In the United States, nearly 1.2 million people > 12 years old have human immunodeficiency virus (HIV), which is associated with postoperative complications following orthopedic procedures. Little is known about how asymptomatic HIV (AHIV) patients fare postoperatively. This study compares complications after common spine surgeries between patients with and without AHIV. The Nationwide Inpatient Sample (NIS) was retrospectively reviewed from 2005-2013, identifying patients aged > 18 years who underwent 2-3-level anterior cervical discectomy and fusion (ACDF), ≥4-level thoracolumbar fusion (TLF), or 2-3-level lumbar fusion (LF). Patients with AHIV and without HIV were 1:1 propensity score-matched. Univariate analysis and multivariable binary logistic regression were performed to assess associations between HIV status and outcomes by cohort. 2-3-level ACDF (n = 594 total patients) and ≥4-level TLF (n = 86 total patients) cohorts demonstrated comparable length of stay (LOS), rates of wound-related, implant-related, medical, surgical, and overall complications between AHIV and controls. 2-3-level LF (n = 570 total patients) cohorts had comparable LOS, implant-related, medical, surgical, and overall complications. AHIV patients experienced higher postoperative respiratory complications (4.3% vs. 0.4%,). AHIV was not associated with higher risks of medical, surgical, or overall inpatient postoperative complications following most spine surgical procedures. The results suggest the postoperative course may be improved in patients with baseline control of HIV infection.

Thirty-Day Outcomes of Resolute Onyx Stent for Symptomatic Intracranial Stenosis: A Multicenter Propensity Score-Matched Comparison With Stenting Versus Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis Trial.

BACKGROUND: Symptomatic intracranial atherosclerotic disease (sICAD) is estimated to cause 10% of strokes annually in the United States. However, treatment remains a challenge with several different stenting options studied in the past with unfavorable results. OBJECTIVE: To report the 30-day stroke and/or death rate associated with intracranial stent placement for sICAD using Resolute Onyx Zotarolimus-Eluting Stent (RO-ZES) and provide a comparison with the results of Stenting Versus Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) trial. METHODS: Prospectively maintained databases across 8 stroke centers were used to identify adult patients treated with RO-ZES for sICAD between January 2019 and December 2021. Primary end point was composite of 30-day stroke, intracerebral hemorrhage, and/or death. Propensity score matching was performed using age, hypertension, lipid disorder, cigarette smoking, and symptomatic target vessel to create a matched group for comparison between RO-ZES and the SAMMPRIS medical management and treatment groups (SAMMPRIS percutaneous angioplasty and stenting [S-PTAS]). RESULTS: A total of 132 patients met the inclusion criteria for analysis (mean age: 64.2 years). Mean severity of stenosis was 81.4% (±11.4%). A total of 4 (3.03%) stroke and/or deaths were reported within 30 days of treatment in the RO-ZES group compared with 6.6% in the SAMMPRIS medical management group (OR [odds ratio] 2.26, 95% CI 0.7-9.56, P = .22) and 15.6% in the S-PTAS group (OR 5.9, 95% CI 2.04-23.4, P < .001). Propensity score match analysis of 115 patients in each group demonstrated 30-day stroke and/or death rate of 2.6% in the RO-ZES group and 15.6% in the S-PTAS group (OR 6.88, 95% CI 1.92-37.54, P < .001). CONCLUSION: Patients treated with RO-ZES had a relatively low 30-day stroke and/or death rate compared with the S-PTAS group. Further large-scale prospective studies are warranted to evaluate the safety and efficacy of RO-ZES for the treatment of sICAD.

The Risk of Adverse Events in Smokers Undergoing Spinal Fusion: A Systematic Review and Meta-Analysis.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVES: Determine if tobacco use is associated with increased risk of postoperative adverse events within 90 days in patients undergoing spinal fusion surgery. METHODS: Databases were queried to identify cohort studies that directly compared smokers with non-smokers and provided the absolute number of adverse events and the population at risk. Data quality was evaluated using the Quality in Prognosis Studies tool. Risk ratios (RR) and 95% confidence intervals were calculated and compared between studies. The grading of recommendation, assessment, development and evaluation (GRADE) criteria were used to assess the strength of the evidence. RESULTS: Seventeen studies assessing 37 897 participants met the inclusion criteria. Of these, 10 031 (26.5%) were smokers and 27 866 (73.5%) were nonsmokers. The mean age for the study population was 58 years, and 45% were males. Smoking was not associated with increased risk of one or more major adverse events within 90 days following spine surgery (seven studies, pooled RR 1.13, 95% CI [.75-1.71], I2 = 41%). However, smoking was significantly associated with one or more major adverse events in ≤2 level fusion (three studies, pooled RR 2.46, 95% CI [1.18-5.12], I2 = 0%), but not in fusions of ≥3 levels (four studies, pooled RR .87, 95% CI [.70-1.08], I2 = 0%). Additionally, there was no statistically significant association between smoking and any adverse event, nor increased reoperation risk due to adverse events. CONCLUSIONS: In this meta-analysis, tobacco use was not associated with a statistically significant increased risk of adverse events within 90 days in patients undergoing spinal fusion surgery. Our results are limited by the variable reporting methodology for both complication rates as well as smoking incidence between the included individual studies.

Complication rates following stand-alone lateral interbody fusion: a single institution series after 10 years of experience.

PURPOSE: This retrospective single institution study's goal was to analyze and report the complications from stand-alone lateral lumbar interbody fusions (LLIF). METHODS: This research was approved by the institutional review board (STUDY2021000113). We retrospectively reviewed the database of patients with adult degenerative spine deformity treated via LLIF at our institution between January 2016 and December 2020. RESULTS: Stand-alone LLIF was performed in 158 patients (145 XLIF, 13 OLIF; mean age 65 y.; 88 f., 70 m.). Mean surgical time was 85 min (± 24 min). Mean follow-up was 14 months (± 5 m). Surgical blood loss averaged 120 mL (± 187 mL) and the mean number of fused levels was 1.2 (± 0.4 levels). Overall complication rate was 19.6% (31 total; 23 approach-related, 8 secondary complications). CONCLUSION: Lateral interbody fusion appears to be a safe surgical intervention with relatively low complication- and revision rates.

Incidence, Management, and Outcomes of Adult Spinal Chordoma Patients in the United States.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: Spinal chordomas are rare primary malignant neoplasms of the primitive notochord. They are slow growing but locally aggressive lesions that have high rates of recurrence and metastasis after treatment. Gold standard treatment remains en-bloc surgical resection with questionable efficacy of adjuvant therapies such as radiation and chemotherapy. Here we provide a comprehensive analysis of prognostic factors, treatment modalities, and survival outcomes in patients with spinal chordoma. METHODS: Patients with diagnosis codes specific for chordoma of spine, sacrum, and coccyx were queried from the National Cancer Database (NCDB) during the years 2004-2016. Outcomes were investigated using Cox univariate and multivariate regression analyses, and survival curves were generated for comparative visualization. RESULTS: 1,548 individuals were identified with a diagnosis of chordoma, 60.9% of which were at the sacrum or coccyx and 39.1% at the spine. The mean overall survival of patients in our cohort was 8.2 years. Increased age, larger tumor size, and presence of metastases were associated with worsened overall survival. 71.2% of patients received surgical intervention and both partial and radical resection were associated with significantly improved overall survival (P < 0.001). Neither radiotherapy nor chemotherapy administration improved overall survival; however, amongst patients who received radiation, those who received proton-based radiation had significantly improved overall survival compared to traditional radiation. CONCLUSION: Surgical resection significantly improves overall survival in patients with spinal chordoma. In those patients receiving radiation, those who receive proton-based modalities have improved overall survival. Further studies into proton radiotherapy doses are required.

Transotic Approach for Resection of Expansile Endolymphatic Sac Tumor.

Objectives and Design Endolymphatic sac tumors (ELSTs) are rare and indolent tumors that arise from the endolymphatic sac in the posterior petrous ridge. We present a video case report illustrating the use of a transotic approach for resection of an expansile ELST. Setting and Participants A 25-year-old male presented with a multiyear history of worsening left-sided hearing loss, vertigo, and headaches. Otoscopy revealed a red mass behind an intact tympanic membrane. Computed tomography revealed a large, locally aggressive mass centered in the posterior petrous temporal bone. Magnetic resonance imaging demonstrated a heterogeneously enhancing 2.4 × 3.1 × 2.4 cm tumor that exerted mass effect on the cerebellar surface with extension into the jugular foramen, tympanic cavity, internal auditory canal, and cistern of the cerebellopontine angle. A transotic approach was planned to obtain the necessary generous exposure. Main Outcome Measures and Results Preoperative angiography revealed arterial supply via the ascending pharyngeal and tumor embolization with Onyx was performed. Surgical resection began with a blind-sac closure created from the external auditory canal. The tympanic membrane and malleus were removed and the incustapedial joint was transected. A subtotal petrosectomy was performed for partial tumor exposure. The facial canal and sigmoid sinus were carefully skeletonized and a labrynthectomy was performed. The tumor was resected using a combination of bipolar cautery and blunt and sharp dissection. For closure, an abdominal fat graft was secured with overlying resorbable mesh followed by sequential closure of all skin layers. Histopathologic analysis revealed an ELST. Conclusion The transotic approach offers wide exposure and facilitates large, complex tumor removal. The link to the video can be found at https://youtu.be/YvhyN8iVi44 .

Early Hyperchloremia and Outcomes After Severe Traumatic Brain Injury: Analysis of Resuscitation Outcomes Consortium Hypertonic Saline Trial.

To investigate the effect of the occurrence of early hyperchloremia on death or severe disability at 180 days in patients with severe traumatic brain injury (TBI). DESIGN: Post hoc analysis of Resuscitation Outcomes Consortium Hypertonic Saline (ROC HS)-TBI trial. SETTING: A total of 114 North American emergency medical services agencies in the ROC. PATIENTS: A total of 991 patients with severe TBI and Glasgow Coma Scale score of less than or equal to 8. INTERVENTIONS: Prehospital resuscitation with single IV dose (250 cc) of 7.5% saline in 6% dextran-70, 7.5% saline (no dextran), or crystalloid. MEASUREMENTS AND MAIN RESULTS: Patients with increased serum chloride concentrations (110 mmol/L or greater) 24 hours after randomization were identified. Hyperchloremia was graded into one or greater than or equal to 2 occurrences in the first 24 hours. Logistic regression analyses were performed to determine the effects of hyperchloremia on: 1) death or severe disability at 180 days and 2) death within 180 days after adjusting for confounders. Compared with patients without hyperchloremia, patients with greater than or equal to 2 occurrences of hyperchloremia had significantly higher odds of death or severe disability at 180 days (odds ratio [OR], 1.81; 95% CI, 1.19-2.75) and death within 180 days (OR, 1.89; 95% CI, 1.14-3.08) after adjustment for confounders. However, the total volume of fluids administered during the first 24 hours was an independent predictor of death within 180 days; therefore, after adding an interaction term between the total volume of fluids administered during the first 24 hours and greater than or equal to 2 occurrences of hyperchloremia, patients with greater than or equal to 2 occurrences of hyperchloremia had significantly higher odds of death within 180 days (OR, 2.35; 95% CI, 1.21-4.61 d) but not of composite outcome of death or severe disability at 180 days. CONCLUSIONS: After modifying for the effect of the total volume of fluids administered during the first 24 hours, multiple occurrences of hyperchloremia in the first 24 hours were associated with higher odds of death within 180 days in patients with severe TBI.

Chordoma of the Skull Base: A National Cancer Database Analysis of Current Practice Patterns and Outcomes.

BACKGROUND: Chordomas of the skull base are aggressive locally destructive tumors that arise from the remnants of the fetal notochord. Current guidelines recommend maximal safe surgical resection followed by adjuvant radiation therapy. However, because of the rarity of these tumors, the optimal radiotherapeutic regimen regarding dose and modality is unclear. METHODS: The National Cancer Database (NCDB) was queried from 2004 to 2016. Data from adult patients were extracted, including tumor characteristics, comorbidity indices, and details of treatment (surgery, radiation, and chemotherapy). The primary outcome of interest was overall survival (OS), which was evaluated for specific treatment cohorts using Cox univariate and multivariate regression constructs along with associated survival curves. RESULTS: We identified 798 patients with a diagnosis of skull base chordoma. Mean OS in this cohort was 9.57 years. Most patients received surgical resection (89.1%), with 53.9% receiving radiotherapy and 6.5% receiving chemotherapy. After adjusting for baseline characteristics using multivariate regression, advanced age and increased tumor size were associated with decreased OS. Surgical resection was associated with increased OS, whereas neither radiotherapy nor chemotherapy was associated with OS. However, in patients who did receive radiation, dosage >6000 cGy was associated with increased OS (hazard ratio, 0.51; P = 0.038); OS did not vary significantly between traditional and proton-based methods. CONCLUSIONS: Our multi-institutional analysis supports the use of partial and radical surgical resection to improve survival in patients with skull base chordomas. Among patients who receive radiotherapy, higher radiation dose is associated with improved survival.

The role of bone mineral density in adult spinal deformity patients undergoing corrective surgery: a matched analysis.

STUDY DESIGN: Retrospective cohort. BACKGROUND: Over 44 million adults are estimated to have either osteoporosis or osteopenia. Adult spinal deformity (ASD) is estimated to affect between 32 and 68% of the elderly population. OBJECTIVE: Retrospective investigation comparing rates of postoperative complications following thoracolumbar scoliosis surgery in patients with normal bone mineral density (BMD) to those with osteopenia or osteoporosis in addition to analyzing the effects of pretreatment with anti-osteoporotic medications in patients with low BMD. METHODS: Using administrative database of Humana beneficiaries, ICD-9 and ICD-10 diagnosis codes were used to identify ASD patients undergoing multilevel thoracolumbar fusions between 2007 and 2017. RESULTS: The propensity matched population analyzed in this study contained 1044 patients equally represented by those with a history of osteopenia, osteoporosis, or normal BMD. Osteopenia and osteoporosis were associated with increased odds of revision surgery (OR 2.01 95% CI 1.36-2.96 and OR 1.57, 95% CI 1.05-2.35), respectively. Similarly, there was an almost twofold increased odds of proximal and distal junctional kyphosis in patients with osteopenia and osteoporosis (OR 1.95, 95% CI 1.40-2.74 and OR 1.88, 95% CI 1.34-2.64), respectively. A total of 258 (37.1%) patients with osteoporosis were pretreated with anti-osteoporotic medications and there was no statistically significant decrease in odds of proximal or distal junctional kyphosis or revision surgery in these patients. CONCLUSION: Patients with ASD undergoing multilevel thoracolumbar fusion surgery have significantly higher rates of postoperative pseudarthrosis, proximal and distal junctional kyphosis, and revision surgery rates compared to patients with normal BMD.

Bone Morphogenetic Protein in Anterior Lumbar Interbody Fusions: A Propensity-Matched Medicare Outcome Analysis.

BACKGROUND: Bone morphogenetic protein (BMP) is a costly agent commonly used in spine surgery. Its effectiveness and complication profile have never been studied in a large, propensity-matched population following its approval by the Food and Drug Administration for use in single-level anterior lumbar interbody fusion (ALIF) surgeries. OBJECTIVE: To investigate the rate of symptomatic pseudarthrosis or need for revision surgery after single-level stand-alone ALIFs with and without the use of BMP. METHODS: Medicare Standard Analytic files derived from Medicare parts A and B were used to identify adult patients who underwent single-level ALIF procedures with and without use of BMP between 2004 and 2014. Patients were propensity matched based on their age, gender, and history of diabetes mellitus, hypertension, chronic kidney disease, body mass index greater than 30 kg/m2, smoking, rheumatoid arthritis, and osteoporosis. Sensitivity analysis using adjusted multivariate logistic regression models was also performed. The primary outcomes were the rates of symptomatic pseudarthrosis or need for revision surgery. RESULTS: The propensity-matched population analyzed in this study contained 22,380 patients undergoing single-level ALIF (8971 [40.6%] with BMP and 13,139 [59.4%] without BMP). Both patient groups were balanced at baseline. The rate of symptomatic pseudarthrosis in the propensity-matched analysis was higher in the BMP group (1.9% vs 1.4%, P < 0.05). BMP use during single-level ALIFs was associated with 44% increased odds of developing pseudarthrosis (OR 1.44, 95% CI 1.16-1.76). However, there was no statistically significant difference in the rate of revision surgery between groups (3.7% vs 3.5%, P = 0.49). CONCLUSIONS: BMP use in single-level ALIFs may be associated with increased risk of symptomatic pseudarthrosis. Large prospective pragmatic trials are needed to corroborate our findings.