Age is Associated with Level of First-Time Anterior Cervical Discectomy and Fusion: An Ordinal Analysis of Factors Influencing Timing of Cervical Degeneration.

BACKGROUND: Symptomatic cervical spondylosis is often treated with anterior cervical discectomy and fusion (ACDF). However, few factors can predict which cervical level will degenerate and require intervention. This analysis evaluates preprocedural factors associated with level of first-time single-level ACDF. METHODS: We performed a retrospective analysis of patients who underwent single-level ACDF without prior history of spine surgery. Mann Whitney U-tests and Spearman rank-order correlation were performed for analyses of associations between variables of interest and ACDF level. Adjusted odds-ratios were calculated by proportional-odds logistic regression, with age, sex, body mass index, current tobacco use, history of neck trauma, preoperative radicular symptoms, and preoperative myelopathic symptoms as covariates. RESULTS: One hundred forty-one patients met inclusion criteria, and age demonstrated a negative correlation with ACDF level, such that younger patients tended to have ACDF performed at inferior subaxial levels (P = 0.0006, rho = -0.31, moderately strong relationship). Patients with preoperative radicular symptoms and myelopathic symptoms were more likely to have ACDF performed at inferior (P = 0.0001) and superior (P < 0.0001) levels, respectively. Patient sex, body mass index, current tobacco use, and history of neck trauma were not predictive of ACDF level. When adjusting for the above variables in a proportional-odds ordinal logistic regression model, a one-year increase in age conferred a 4% increase in the odds of requiring an ACDF at a given superior level compared to the adjacent inferior level. CONCLUSIONS: Age is correlated with level of first-time single level ACDF. Individual subaxial levels may have unique biomechanical properties that influence degeneration.

A 3-Year Study Investigating the Utility of Patient-Reported Outcomes Measurement Information System-29 for Long-Term Follow-Up in Adult Spinal Deformity.

BACKGROUND: Adult spinal deformity (ASD) significantly impacts the quality of life due to three-dimensional spinal abnormalities. Patient-reported outcome measures, such as the Patient-Reported Outcomes Measurement Information System (PROMIS-29), play a crucial role in assessing postoperative outcomes. This study aims to investigate trends in PROMIS-29 scores over 36 months in patients undergoing long-segment thoracolumbar fusion for ASD and provide insights into its long-term utility. METHODS: A retrospective study including 163 ASD patients undergoing long-segment thoracolumbar fusion was conducted. PROMIS-29 scores were collected at baseline and at postoperative (0-), 3-, 6-, 12-, 18-, 24-, 30-, and 36-month follow-ups. Statistical analyses was performed to assess significant score changes from baseline and in consecutive recordings. RESULTS: Significant improvements in all PROMIS-29 categories were observed at 36 months, with the greatest changes in pain intensity (-35.19%, P < 0.001), physical function (+29.13%, P < 0.001), and pain interference (-28.8%, P < 0.001). Between the 0 and 3 month mark, the greatest significant changes were recorded in pain intensity (-26.5%, P < 0.001), physical function (+24.3%, P < 0.001), and anxiety (-16.9%, P < 0.018). However, scores plateaued after the 3-month mark, with zero categories showing significant changes with subsequent consecutive recordings. CONCLUSIONS: PROMIS-29 scores demonstrated notable improvements in ASD patients particularly in pain intensity, pain interference, and physical function. However, scores plateaued beyond the 3-month mark, suggesting PROMIS-29's limited sensitivity to nuanced changes in long-term patient recovery. Future investigations exploring optimal combinations of patient reported outcome measures for comprehensive short- and long-term outcome assessments in ASD surgery would be beneficial.

3D-Printed Spine Models for Planning Staged Minimally Invasive Transverse Process Resections for Bertolotti Syndrome: Technical Note.

Background: Three-dimensional (3D) printing has enabled numerous advances in spine surgery execution and education. However, few examples exist to outline how this technology can aid the performance of complex spine surgery using minimally invasive surgery (MIS) techniques. Therefore, we present a case that illustrates the benefits of 3D-printed spine model production before and after correction of a congenital lumbosacral anomaly using an MIS approach. Case Report: A 40-year-old woman with Bertolotti syndrome underwent a staged bilateral L6 MIS transverse process resection for the treatment of severe and progressive axial back pain which had repeatedly failed conservative management. 3D-printed spine models were used for pre- and post-operative surgical planning and patient counseling. Conclusion: 3D-printed spine models can aid in the planning of complex spine cases suited for an MIS approach.

Trends of the Oswestry Disability Index in Adult Spinal Deformity Patients: A 3-Year Study.

BACKGROUND: Patients with adult spinal deformity (ASD) undergoing operative treatment may have varying degrees of improvement in patient-reported outcomes. The Oswestry Disability Index (ODI) assesses improvement in quality of life. We aim to measure longitudinal outcomes of ODI scores over 3 years to determine if early ODI scores predict late ODI scores and to analyze longitudinal changes in ODI scores. METHODS: Two hundred thirty-five patients above the age of 18 who underwent surgical correction of ASD at a single institution from 2016 to 2021 and completed ODI questionnaires at follow-up appointments met inclusion criteria. ODI scores were included from follow-up visits at 0 months (immediately postoperative) and within ±1 month of 3, 6, 12, 18, 24, 30, and 36 months. Percent change in ODI from 0 months was calculated, and unpaired t tests were conducted. RESULTS: ODI scores increased by 8.8% immediately postoperatively, and the percent change from preoperative ODI scores at each subsequent visit were as follows: -11.1% at 3 months, -21.4% at 6 months, -25.4% at 12 months, -28% at 18 months, -31.3% at 24 months, -25.7% at 30 months, and -36.5% at 36 months. ODI scores at each follow-up visit showed significant improvement from baseline (P < 0.001). There was an improvement in scores from 3 to 6 months (P = 0.04), but no significant difference in 6-month interval visits following 6 months. CONCLUSIONS: Our results demonstrate a significant and sustained improvement in ODI scores over 3 years following surgical correction of ASD. ODI scores were stable after 6 months, indicating that ODI scores at 6 months may be predictive of scores out to 3 years postoperatively. Examining individual components of ODI sub-scores and comparing ODI results to other PROMs are critical to better assess long-term outcomes in ASD.

Identifying Correlation Among Patient-Reported Outcome Measures: A Study of PROMIS-29, ODI, and VAS in Adult Spinal Deformity Patients.

BACKGROUND: Adult spinal deformity (ASD) is becoming increasingly common in aging populations. Patient-reported outcome measures (PROMs) are self-reported patient surveys administered pre- and postoperatively that provide insight into patient improvement. We aim to compare 3 of the most utilized PROMs: PROMIS-29, Oswestry Disability Index (ODI), and Visual Analogue Scale (VAS), to investigate whether they provide unique and independent assessments of patient outcomes when assessed longitudinally. METHODS: We retrospectively reviewed a database of ASD at UT Southwestern Medical Center between 2016 and 2021. Adult patients (>18 years old) were included if they underwent long-segment (>4 levels) thoracolumbar fusion. PROMIS-29, ODI, and VAS scores were collected preoperatively and at 3-, 6-, 12-, 18-, 24-, 30-, and 36-month follow-ups. Scores were recorded ±1 month of the time points. Pearson correlation coefficients for each PROM were then calculated in a pairwise fashion. RESULTS: A total of 163 patients were included in our analysis. ODI and VAS showed significant covariance, with VAS Neck and VAS Back having Pearson coefficients of 0.95 and 0.94, respectively. ODI and PROMIS-29 also showed significant covariance, with Physical Function and ODI showing a Pearson coefficient of 0.95. PROMIS-29 and VAS demonstrated less correlation regarding Pain and Physical Function; however, they showed a significantly high Pearson coefficient when comparing VAS Back with PROMIS-29 Sleep and Pain Intensity (r = 0.97 and r = 0.96, respectively). CONCLUSIONS: All 3 PROMs demonstrated significant correlation over 36 months, indicating that simultaneous administration of each during follow-up is redundant. The measure that provided the least unique information was ODI, as both VAS and PROMIS-29 demonstrated similar progression and assessed additional metrics. PROMIS-29 provided the same information as VAS and ODI, with extra facets of patient-reported outcomes, indicating that it may be a more comprehensive measure of longitudinal patient improvement.

Alexa Irene Canady: First Female African American Neurosurgeon of the United States.

BACKGROUND: This historical account reviews the course and lasting impact of Dr. Alexa Irene Canady in neurosurgery. METHODS: The writing of this project was sparked by the discovery of original scientific and bibliographical information about Alexa Canady, the first female African-American neurosurgeon in the nation. This article is a thorough review of the literature and information on Canady, reflecting the breadth of these previous publications, and showcasing our viewpoints after comprehensive compilation of information. RESULTS: Our paper begins by introducing Dr. Alexa Irene Canady and her decision to pursue a career in medicine during her years in university; follows her journey through medical school and growing interests in neurosurgery; outlines her journey in residency; discusses her career as an established pediatric neurosurgeon at the University of Michigan; outlines her role in establishing a department of pediatric neurosurgery in Pensacola, Florida; and details the obstacles and challenges she faced throughout her career, as well as the barriers she broke along the way. CONCLUSIONS: Our article provides glimpses into the personal life and achievements of Dr. Alexa Irene Canady and her marked impact on the field of neurosurgery.

Image-Guided Percutaneous Multilevel Pediculosynthesis for Treatment of Contiguous Pedicle Stress Fractures: Technical Case Report.

BACKGROUND: Nontraumatic pedicle fracture is uncommon, with sparsely described cases of conservative management versus surgical treatment by open fusion or percutaneous fixation. METHODS: We report the case of a 60-year-old woman with nontraumatic L4 and L5 pedicle fracture who developed additional pedicle fractures at L3 while undergoing conservative management in a brace. The patient underwent percutaneous pediculosynthesis with screw fixation without fusion at L3-5 bilaterally. RESULTS: The treatment led to fracture healing with good radiographic result and resolution of her symptoms. CONCLUSIONS: A trial of conservative management is typically warranted in most cases of nontraumatic pedicle fracture, but there is risk of refractory or progressive symptoms and subsequent fracture. Minimally invasive fixation is a viable surgical option that can be used in multilevel fractures.

Single Nucleotide Polymorphisms and Adolescent Idiopathic Scoliosis: A Systematic Review and Meta-Analysis of the Literature.

STUDY DESIGN: Meta-analysis. OBJECTIVE: To determine the single nucleotide polymorphisms (SNPs) that are related to adult idiopathic scoliosis. SUMMARY AND BACKGROUND DATA: Adolescent idiopathic scoliosis (AIS) is considered one of the most prevalent spinal diseases. Even though the cause of AIS is yet to be determined, family history and sex have shown conclusive associations. Multiple studies have indicated that AIS is more prevalent in families where at least one other first-degree relative is similarly affected, indicating a possible genetic etiology to AIS. MATERIALS AND METHODS: Articles were collected from 3 different search engines and then processed in 2 stages for final article selection for quantitative analysis. Five different genetic models were represented to show the association between the different SNPs and AIS. The Hardy-Weinberg equilibrium was examined using Fisher exact test, with significance set at P <0.05. The final analysis paper's quality was evaluated using the Newcastle Ottawa Scale. Kappa interrater agreement was calculated to evaluate the agreement between authors. RESULTS: The final analysis comprised 43 publications, 19412 cases, 22005 controls, and 25 distinct genes. LBX1 rs11190870 T>C and MATN-1 SNPs were associated with an increased risk of AIS in one or all of the 5 genetic models. IGF-1 , estrogen receptor alfa, and MTNR1B , SNPs were not associated with AIS in all 5 genetic models. Newcastle Ottawa Scale showed good quality for the selected articles. Cohen k = 0.741 and Kappa interrater agreement of 84% showed that the writers were in strong agreement. CONCLUSIONS: There seem to be associations between AIS and genetic SNP. Further larger studies should be conducted to validate the results.

Impact of obesity on complications and surgical outcomes after adult degenerative scoliosis spine surgery.

OBJECTIVE: To compare perioperative outcomes of obese versus non-obese adult patients who underwent degenerative scoliosis spine surgery. METHODS: 235 patients who underwent thoracolumbar adult spinal deformity (ASD) surgery (≥4 levels) were identified and categorized into two cohorts based on their body mass indices (BMI): obese (BMI ≥30 kg/m2; n = 81) and non-obese (BMI <30 kg/m2; n = 154). Preoperative (demographics, co-morbidities, American Society of Anesthesiologists (ASA) score and modified frailty indices (mFI-5 and mFI-11)), intraoperative (estimated blood loss (EBL) and anesthesia duration), and postoperative (complication rates, Oswestry Disability Index (ODI) scores, discharge destination, readmission rates, and survival) characteristics were analyzed by student's t, chi-squared, and Mann-Whitney U tests. RESULTS: Obese patients were more likely to be Black/African-American (p < 0.05, OR:4.11, 95% CI:1.20-14.10), diabetic (p < 0.05, OR:10.18, 95% CI:4.38-23.68) and had higher ASA (p < .01) and psoas muscle indices (p < 0.0001). Furthermore, they had greater pre- and post-operative ODI scores (p < 0.05) with elevated mFI-5 (p < 0.0001) and mFI-11 (p < 0.01). Intraoperatively, obese patients were under anesthesia for longer time periods (p < 0.05) with higher EBL (p < 0.05). Postoperatively, while they were more likely to have complications (OR:1.77, 95% CI:1.01 - 3.08), had increased postop days to initiate walking (p < .05) and were less likely to be discharged home (OR:0.55, 95% CI:0.31-0.99), no differences were found in change in ODI scores or readmission rates between the two cohorts. CONCLUSIONS: Obesity increases pre-operative risk factors including ASA, frailty and co-morbidities leading to longer operations, increased EBL, higher complications and decreased discharge to home. Pre-operative assessment and systematic measures should be taken to improve peri-operative outcomes.

VertebralArtery Injury with Anterior Cervical Spine Operations: A Systematic Review of Risk Factors, Clinical Outcomes, and Management Strategies.

OBJECTIVE: Anterior cervical spine operations are commonly performed on cervical spine pathologies and to a large extent are safe and successful. However, these surgical procedures expose the vertebral artery, posing a risk of harm to it. METHODS: A systematic review was conducted using PubMed, Google Scholar, and Web of Science electronic databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to critically assess primary articles discussing treatment strategies "vertebral artery injury" AND "anterior cervical spine" and develop a management strategy based on our experience and meta-analysis of the literature. In addition, we present an illustrative case of iatrogenic vertebral artery injury presenting with 6 to 7 months' history of progressive dysphagia was transferred to our care from an outside institution. RESULTS: Included and analyzed were 43 articles that detailed 75 cases involving vertebral artery injury (VAI) in anterior cervical spine operations. Preoperatively, frequent clinical findings reported were sensory deficit (26 patients [63.41%]), motor deficit (20 patients [48.78%]), and pain (17 patients [41.46%]). In total, 32 patients (50.00%) endured injury of their left VA, and 30 patients had a right VAI. The 2 common causes of VAI were drilling (24 patients [40.00%]) and instrumentation (8 patients [13.33%]). CONCLUSIONS: Altogether, our review recommends repair or tamponade packing with a hemostatic agent for primary management. Should tamponade packing with a hemostatic agent be used for primary management, secondary management should entail either repair, stenting occlusion, embolization, anticoagulants, or ligation. Further examination of this treatment strategy based on a larger cohort is necessary.

Household Income as a Predictor for Surgical Outcomes and Opioid Use After Spine Surgery in the United States.

STUDY DESIGN: Cross-Sectional Study. OBJECTIVES: Socioeconomic status (SES) is a fundamental root of health disparities, however, its effect on surgical outcomes is often difficult to capture in clinical research, especially in spine surgery. Here, we present a large single-center study assessing whether SES is associated with cause-specific surgical outcomes. METHODS: Patients undergoing spine surgery between 2015 and 2019 were assigned income in accordance with the national distribution and divided into quartiles based on the ZIP code-level median household income. We performed univariate, chi-square, and Analysis of Variance (ANOVA) analysis assessing the independent association of SES, quantified by household income, to operative outcomes, and multiple metrics of opioid consumption. RESULTS: 1199 patients were enrolled, and 1138 patients were included in the analysis. Low household income was associated with the greatest rates of 3-month opioid script renewal (OR:1.65, 95% CI:1.14-2.40). In addition, low-income was associated with higher rates of perioperative opioid consumption compared to higher income including increased mean total morphine milligram equivalent (MME) 252.25 (SD 901.32) vs 131.57 (SD 197.46) (P < .046), and inpatient IV patient-controlled analgesia (PCA) MME 121.11 (SD 142.14) vs 87.60 (SD 86.33) (P < .023). In addition, household income was independently associated with length of stay (LOS), and emergency room (ER) revisits with low-income patients demonstrating significantly longer postop LOS and increasing postoperative ER visits. CONCLUSIONS: Considering the comparable surgical management provided by the single institution, the associated differences in postoperative outcomes as defined by increased morbidities and opioid consumption can potentially be attributed to health disparities caused by SES.

Psoas Muscle Index as a Predictor of Perioperative Outcomes in Geriatric Patients Undergoing Spine Surgery.

STUDY DESIGN: Single-center retrospective study. OBJECTIVE: The objective of this study was to evaluate the association of psoas muscle mass defined sarcopenia with perioperative outcomes in geriatric patients undergoing elective spine surgery. METHODS: We included geriatric patients undergoing thoracolumbar spinal surgery. Total psoas surface area (TPA) was measured on preoperative axial computerized tomography or magnetic resonance imaging at the L3 vertebra and normalized to the L3 vertebral body area. Patients were divided into quartiles by normalized TPA, and the fourth quartile (Q4) was compared to quartiles 1-3 (Q1-3). Outcomes included perioperative transfusions, length of stay (LOS), delirium, pseudoarthrosis, readmission, discharge disposition, revision surgery, and mortality. RESULTS: Of the patients who met inclusion criteria (n = 196), the average age was 73.4 y, with 48 patients in Q4 and 148 patients in Q1-3. Q4 normalized TPA cut-off was <1.05. Differences in Q4 preoperative characteristics included significantly lower body mass index, baseline creatinine, and a greater proportion of females (Table 1). Q4 patients received significantly more postoperative red blood cell and platelet transfusions and had longer ICU LOS (P < .05; Table 2). There was no difference in intraoperative transfusion volumes, delirium, initiation of walking, discharge disposition, readmission, pseudoarthrosis, or revision surgery (Tables 2 and 3). Mortality during follow-up was higher in Q4 but was not statistically significant (P = .075). CONCLUSION: Preoperative TPA in geriatric patients undergoing elective spine surgery is associated with increased need for intensive care and postoperative blood transfusion. Preoperative normalized TPA is a convenient measurement and could be included in geriatric preoperative risk assessment algorithms.

Development and Internal Validation of the Postoperative Analgesic Intake Needs Score: A Predictive Model for Post-Operative Narcotic Requirement after Spine Surgery.

STUDY DESIGN: Retrospective Cohort. OBJECTIVE: The aim of this study was to develop a clinical tool to pre-operatively risk-stratify patients undergoing spine surgery based on their likelihood to have high postoperative analgesic requirements. METHODS: A total of 1199 consecutive patients undergoing elective spine surgery over a 2-year period at a single center were included. Patients not requiring inpatient admission, those who received epidural analgesia, those who had two surgeries at separate sites under one anesthesia event, and those with a length of stay greater than 10 days were excluded. The remaining 860 patients were divided into a derivation and validation cohort. Pre-operative factors were collected by review of the electronic medical record. Total postoperative inpatient opioid intake requirements were converted into morphine milligram equivalents to standardize postoperative analgesic requirements. RESULTS: The postoperative analgesic intake needs (PAIN) score was developed after the following predictor variables were identified: age, race, history of depression/anxiety, smoking status, active pre-operative benzodiazepine use and pre-operative opioid use, and surgical type. Patients were risk-stratified based on their score with the high-risk group being more likely to have high opioid consumption postoperatively compared to the moderate and low-risk groups in both the derivation and validation cohorts. CONCLUSION: The PAIN Score is a pre-operative clinical tool for patients undergoing spine surgery to risk stratify them based on their likelihood for high analgesic requirements. The information can be used to individualize a multi-modal analgesic regimen rather than utilizing a "one-size fits all" approach.

Perioperative Factors Associated With Chronic Opioid Use After Spine Surgery.

STUDY DESIGN: Retrospective case control. OBJECTIVES: The purpose of the current study is to determine risk factors associated with chronic opioid use after spine surgery. METHODS: In our single institution retrospective study, 1,299 patients undergoing elective spine surgery at a tertiary academic medical center between January 2010 and August 2017 were enrolled into a prospectively collected registry. Patients were dichotomized based on renewal of, or active opioid prescription at 3-mo and 12-mo postoperatively. The primary outcome measures were risk factors for opioid renewal 3-months and 12-months postoperatively. These primarily included demographic characteristics, operative variables, and in-hospital opioid consumption via morphine milligram equivalence (MME). At the 3-month and 12-month periods, we analyzed the aforementioned covariates with multivariate followed by bivariate regression analyses. RESULTS: Multivariate and bivariate analyses revealed that script renewal at 3 months was associated with black race (P = 0.001), preoperative narcotic (P < 0.001) or anxiety/depression medication use (P = 0.002), and intraoperative long lumbar (P < 0.001) or thoracic spine surgery (P < 0.001). Lower patient income was also a risk factor for script renewal (P = 0.01). Script renewal at 12 months was associated with younger age (P = 0.006), preoperative narcotics use (P = 0.001), and ≥4 levels of lumbar fusion (P < 0.001). Renewals at 3-mo and 12-mo had no association with MME given during the hospital stay or with the usage of PCA (P > 0.05). CONCLUSION: The current study describes multiple patient-level factors associated with chronic opioid use. Notably, no metric of perioperative opioid utilization was directly associated with chronic opioid use after multivariate analysis.

A Comparative Analysis of Frailty, Disability, and Sarcopenia With Patient Characteristics and Outcomes in Adult Spinal Deformity Surgery.

STUDY DESIGN: Retrospective case series study. OBJECTIVES: This study aims to compare preoperative indices, including the modified frailty index-11 (mFI-11), modified frailty index-5 (mFI-5), Oswestry Disability Index (ODI), and psoas muscle index (PMI), as they relate to outcomes in adult spinal deformity (ASD) surgery. METHODS: We identified 235 patients who underwent thoracolumbar ASD surgery (≥4 levels). The mFI-11, mFI-5, ODI, and PMI were determined from preoperative visits and correlated to outcome measures, including perioperative transfusion, duration of anesthesia, hospital and ICU length of stay (LOS), discharge disposition, readmission, change in ODI at last follow-up, revision surgery, and mortality. RESULTS: Our cohort had a mean age of 69.6 years and a male:female ratio of 1:2 with 177 undergoing an index surgery and 58 patients presenting after a failed multilevel fusion. The average number of levels fused was 9.3. The mFI-11 and mFI-5 were similar in predicting the need for intraoperative and postoperative transfusion. However, the mFI-11 was able to predict longer ICU and hospital LOS and mortality. The average preoperative ODI was 44.9% with an average decrease of 10.1% at the last follow-up. Preoperative ODI was the most significant predictor of postoperative change of ODI. Sarcopenia, defined as the lowest quartile of PMI values measured at L3 and L4, was not associated with any meaningful outcomes. CONCLUSION: The mFI-11 better correlated with outcomes, indicating its increased prognostic value compared to other preoperative indices in ASD surgery. Preoperative ODI remains a significant predictor of postoperative change in ODI when evaluating ASD patients.

Applying 3-Dimensional Printing and Modeling for Preoperative Reconstruction and Instrumentation Placement Planning in Complex Deformity Surgery.

BACKGROUND: Advances in three-dimensional (3D) printing technology have enabled the development of customized instrumentation and surgical training platforms. However, no existing studies have assessed how patient-specific 3D-printed spine models can facilitate patient education and operative planning in complex spinal deformity correction. OBJECTIVE: To present a cost-effective technique for constructing personalized 3D-printed spine models for patients with severe spinal deformities and to outline how these models can promote informed consent, trainee education, and planning for instrumentation placement and alignment correction. METHODS: We present 2 patients who underwent surgical correction of progressive thoracolumbar deformities. Full-scale 3D-printed models of each patient's spine were produced preoperatively and used during clinic evaluations, surgical planning, and as intraoperative references. RESULTS: Each model took 9 days to build and required less than 60 US dollars of material costs. Both patients were treated with a posterior approach and contiguous multilevel osteotomies. Postoperatively, their alignment parameters and neurological deficits improved. CONCLUSION: Personalized 3D-printed spine models can aid in patient education, surgical training, visualization, and correction of complex spinal deformities.