Clinical presentation and extent of resection impacts progression-free survival in spinal ependymomas.

PURPOSE: Primary treatment of spinal ependymomas involves surgical resection, however recurrence ranges between 50 and 70%. While the association of survival outcomes with lesion extent of resection (EOR) has been studied, existing analyses are limited by small samples and archaic data resulting in an inhomogeneous population. We investigated the relationship between EOR and survival outcomes, chiefly overall survival (OS) and progression-free survival (PFS), in a large contemporary cohort of spinal ependymoma patients. METHODS: Adult patients diagnosed with a spinal ependymoma from 2006 to 2021 were identified from an institutional registry. Patients undergoing primary surgical resection at our institution, ≥ 1 routine follow-up MRI, and pathologic diagnosis of ependymoma were included. Records were reviewed for demographic information, EOR, lesion characteristics, and pre-/post-operative neurologic symptoms. EOR was divided into 2 classifications: gross total resection (GTR) and subtotal resection (STR). Log-rank test was used to compare OS and PFS between patient groups. RESULTS: Sixty-nine patients satisfied inclusion criteria, with 79.7% benefitting from GTR. The population was 56.2% male with average age of 45.7 years, and median follow-up duration of 58 months. Cox multivariate model demonstrated significant improvement in PFS when a GTR was attained (p <.001). Independently ambulatory patients prior to surgery had superior PFS (p <.001) and OS (p =.05). In univariate analyses, patients with a syrinx had improved PFS (p =.03) and were more likely to benefit from GTR (p =.01). Alternatively, OS was not affected by EOR (p =.78). CONCLUSIONS: In this large, contemporary series of adult spinal ependymoma patients, we demonstrated improvements in PFS when GTR was achieved.

Exploring tribology and material contact science in spine surgery: implications for implant design.

Tribology, an interdisciplinary field concerned with the science of interactions between surfaces in contact and their relative motion, plays a well-established role in the design of orthopedic implants, such as knee and hip replacements. However, its applications in spine surgery have received comparatively less attention in the literature. Understanding tribology is pivotal in elucidating the intricate interactions between metal, polymer, and ceramic components, as well as their interplay with the native human bone. Numerous studies have demonstrated that optimizing tribological factors is key to enhancing the longevity of joints and implants while simultaneously reducing complications and the need for revision surgeries in both arthroplasty and spinal fusion procedures. With an ever-growing and diverse array of spinal implant devices hitting the market for static and dynamic stabilization of the spine, it is important to consider how each of these devices optimizes these parameters and what factors may be inadequately addressed by currently available technology and methods. In this comprehensive review, the authors' objectives were twofold: 1) delineate the unique challenges encountered in spine surgery that could be addressed through optimization of tribological parameters; and 2) summarize current innovations and products within spine surgery that look to optimize tribological parameters and highlight new avenues for implant design and research.

Evolution of lumbar degenerative spondylolisthesis with key radiographic features.

Spondylolisthesis is a common finding in middle-aged and older adults with back pain. The pathophysiology of degenerative spondylolisthesis is a subject of controversy regarding not only its etiology but also the mechanisms of its progression. It is theorized that degeneration of the facets and discs can lead to segmental instability, leading to displacement over time. Kirkaldy-Willis divided degenerative spondylolisthesis into three phases: dysfunction, instability, and finally, restabilization. There is a paucity of literature on the unification of the radiological hallmarks seen in spondylolisthesis within these phases. The radiographic features include (1) facet morphology/arthropathy, (2) facet effusion, (3) facet vacuum, (4) synovial cyst, (5) interspinous ligament bursitis, and (6) vacuum disc as markers of dysfunction, instability, and/or restabilization. We discuss these features, which can be seen on X-ray, CT, and MRI, with the intention of establishing a timeline upon which they present clinically. Spondylolisthesis is initiated as either degeneration of the intervertebral disc or facet joints. Early degeneration can be seen as facet vacuum without considerable arthropathy. As the vertebral segment becomes increasingly dynamic, fluid accumulates within the facet joint space. Further degeneration will lead to the advancement of facet arthropathy, degenerative disc disease, and posterior ligamentous complex pathology. Facet effusion can eventually be replaced with a vacuum in severe facet osteoarthritis. Intervertebral disc vacuum continues to accumulate with further cleft formation and degeneration. Ultimately, autofusion of the vertebra at the facets and endplates can be observed. With this review, we hope to increase awareness of these radiographical markers and their timeline, thus placing them within the framework of the currently accepted model of degenerative spondylolisthesis, to help guide future research and to help refine management guidelines.

A Pilot Remote Curriculum to Enhance Resident and Medical Student Understanding of Machine Learning in Healthcare.

BACKGROUND: Despite the expanding role of machine learning (ML) in health care and patient expectations for clinicians to understand ML-based tools, few for-credit curricula exist specifically for neurosurgical trainees to learn basic principles and implications of ML for medical research and clinical practice. We implemented a novel, remotely delivered curriculum designed to develop literacy in ML for neurosurgical trainees. METHODS: A 4-week pilot medical elective was designed specifically for trainees to build literacy in basic ML concepts. Qualitative feedback from interested and enrolled students was collected to assess students' and trainees' reactions, learning, and future application of course content. RESULTS: Despite 15 interested learners, only 3 medical students and 1 neurosurgical resident completed the course. Enrollment included students and trainees from 3 different institutions. All learners who completed the course found the lectures relevant to their future practice as clinicians and researchers and reported improved confidence in applying and understanding published literature applying ML techniques in health care. Barriers to ample enrollment and retention (e.g., balancing clinical responsibilities) were identified. CONCLUSIONS: This pilot elective demonstrated the interest, value, and feasibility of a remote elective to establish ML literacy; however, feedback to increase accessibility and flexibility of the course encouraged our team to implement changes. Future elective iterations will have a semiannual, 2-week format, splitting lectures more clearly between theory (the method and its value) and application (coding instructions) and will make lectures open-source prerequisites to allow tailoring of student learning to their planned application of these methods in their practice and research.

The World Neurosurgery Global Champions Program: First-Year Experience of a Model Initiative for Reducing Disparities in Global Neurosurgical Literature.

OBJECTIVE: Most surgical journals are published in English, representing a challenge for researchers from non-Anglophone countries. We describe the implementation, workflow, outcomes, and lessons learned from the WORLD NEUROSURGERY Global Champions Program (GCP), a novel journal-specific English language editing program for articles rejected because of poor English grammar or usage. METHODS: The GCP was advertised via the journal website and social media. Applicants were selected to be a reviewer for the GCP if they demonstrated English proficiency on writing samples supplied in their application. The demographics of GCP members and characteristics and outcomes of articles edited by the GCP during its first year were reviewed. Surveys of GCP members and authors who used the service were conducted. RESULTS: Twenty-one individuals became part of the GCP, representing 8 countries and 16 languages apart from English. A total of 380 manuscripts were peer reviewed by the editor-in-chief, who determined these manuscripts to have potentially worthwhile content but needed to be rejected due to poor language. The authors of these manuscripts were informed of the existence of this language assistance program. Forty-nine articles (12.9%) were edited by the GCP in 41.6 ± 22.8 days. Of 40 articles resubmitted to WORLD NEUROSURGERY, 24 (60.0%) were accepted. GCP members and authors understood the purpose and workflow of the program and recognized improvements in article quality and the probability of acceptance through their participation. CONCLUSIONS: The WORLD NEUROSURGERY Global Champions Program mitigated a critical barrier to publication in an English language journal for authors from non-Anglophone countries. This program promotes research equity by providing a free, largely medical student and trainee operated, English language editing service. This model or a similar service can be replicated by other journals.

Characterizing the Next Generation of Neurosurgeons: A Descriptive Analysis and Publicly Available Web Application of Neurosurgery Residency Programs' Website Data.

OBJECTIVE: Neurosurgery program websites serve as a valuable resource for applicants. However, each website exists in isolation, and it can be difficult to understand the general trends in U.S. neurosurgery resident demographics. In the present study, we collected data from program websites and analyzed the trends in the demographics of the current U.S. neurosurgery residents. METHODS: We used a program list obtained from the American Association of Medical Colleges Electronic Residency Application System to extract data from the current resident complement listed in each program's website, including program, year in program, medical school, sex (male vs. female), graduate and/or PhD degrees, and assessed the trends during 7 years of resident data using linear regression. RESULTS: We identified 116 neurosurgery residency programs in the United States, with 111 providing information on their current resident complement, yielding a dataset of 1599 residents. Of these 1599 residents, 348 (22%) were female, 301 (19%) had a graduate degree in addition to an MD or DO degree, 151 (9.4%) had a PhD degree, 300 (19%) had matched at the program affiliated with their medical school, and 121 (7.6%) had graduated from a foreign medical school. The proportion of matriculating female residents had increased an average of 2.1% annually (95% confidence interval, 0.6%-3.7%) from 2015 to 2021. The other demographic data had not changed significantly during the same period. CONCLUSIONS: In addition to summarizing the current resident demographics, our analysis identified a significant increase in the proportion of female residents between 2015 (15.1%) and 2021 (25.6%). This publicly available dataset should enable additional analyses of the evolution of neurosurgery resident demographics.

Standardized Interview Scoring Methodology for Neurosurgical Residency Applicant Selection.

Interviews are critical to the neurosurgery resident application process. The COVID-19 pandemic forced residency interview activities are conducted virtually. To maintain a degree of control during a period of uncertainty, our department implemented a standardized survey for interviewers to evaluate the noncognitive attributes and program compatibility of applicants. Our objective was to assess the reliability and biases associated with our standardized interviewer survey implemented in neurosurgical residency interviews. A 5-question interviewer survey to assess applicant interview performance and program compatibility was implemented during the 2020 to 2021 interview season. After the application cycle, survey metrics were retrospectively reviewed. Multiple cohort analyses were performed by dividing interviewers into cohorts based on status (faculty or resident) and sex. Applicant scores were assessed within sex subgroups for each aforementioned interviewer cohort. Intraclass correlation coefficients (ICCs) were calculated to assess survey reliability. Fifteen interviewers (8 faculty and 7 residents) and 35 applicants were included. Female applicants (17%) and interviewers (20%) comprised the minority. There were no differences between resident and faculty reviewer scores; however, female reviewers gave higher overall scores than male reviewers ( P = .003). There was no difference in total scores between female and male applicants when evaluating all reviewers or subgroups of faculty, residents, females, or males. ICC analysis demonstrated good (ICC 0.75-0.90) or excellent (ICC > 0.90) reliability for all questions and overall score. The standardized interviewer survey was a feasible and reliable method for evaluating noncognitive attributes during neurosurgery residency interviews. There was no perceptible evidence of sex bias in our single-program experience.

Mapping PROMIS physical function and pain interference to the modified low back pain disability questionnaire.

PURPOSE: The Modified Low Back Pain Disability Questionnaire (MDQ) is a commonly used tool to assess functioning of patients with low back pain (LBP). Recently, the Patient-Reported Outcomes Measurement Information System (PROMIS) was suggested as an alternative platform to assess LBP patient-reported health. We sought to map between the MDQ and PROMIS Physical Function (PROMIS-PF) and Pain Interference (PROMIS-PI) scales using multiple methods. METHODS: In a retrospective analysis of LBP patients seen at Cleveland Clinic 11/14/18-12/11/19, T-scores from each PROMIS scale were mapped to MDQ total score individually and together. MDQ item and total scores were mapped to each PROMIS scale. Linear regression as well as linear and equipercentile equating were used. Split sample internal validation using root mean squared error (RMSE), mean absolute error (MAE), and correlations were used to assess accuracy of mapping equations. RESULTS: 13585 patients completed the three scales. In the derivation cohort, average age was 59.0 (SD = 15.8); 53.3% female and 82.9% white. Average MDQ total, PROMIS-PF, and PROMIS-PI T-scores were 40.3 (SD = 19.0), 37.2 (SD = 7.6), and 62.9 (SD = 7.2), respectively. For estimating MDQ total scores, methods that used both PROMIS-PF and PROMIS-PI had closest estimated means, lowest RMSE and MAE, and highest correlations. For estimating each of PROMIS-PF and PROMIS-PI T-scores, the best performing method was equipercentile equating using the MDQ items. CONCLUSIONS: We created and internally validated maps between MDQ and PROMIS-PF and PROMIS-PI using linear regression, linear and equipercentile equating. Our equations can be used by researchers wishing to translate scores between these scales.

A Biomechanical Assessment of Shaken Baby Syndrome: What About the Spine?

BACKGROUND: Shaken baby syndrome occurs following inertial loading of the pediatric head, resulting in retinal hemorrhaging, subdural hematoma, and encephalopathy. However, the anatomically vulnerable cervical spine receives little attention. Automotive safety literature is replete with biomechanical data involving forward-facing pediatric surrogates in frontal collisions, an environment analogous to shaking. Publicly available data involving child occupants were utilized to study pediatric neck and head injury potential. We hypothesized that inertial loading provides a greater risk of injury to the cervical spine than to the head. METHODS: Full-scale automotive crash tests (n = 131) and deceleration sled tests (n = 32) utilizing forward-facing 3-year-old surrogates with head accelerometers and cervical force sensors were analyzed. One hundred sixty-seven full-scale vehicle and 33 sled test runs were assessed in the context of published injury assessment reference values (IARVs) for closed head injury (head injury criterion 15 [HIC15]) and cervical tensile strength in the 3-year-old model. RESULTS: One hundred sixty-one (96%) child surrogates in full-scale crash tests exceeded the cervical peak tension IARV, while only 37 (22%) surpassed the HIC15 IARV. Similarly, in sled testing runs, 27 (82%) pediatric surrogates exceeded cervical tension IARVs, while 1 (3%) surpassed the HIC15 IARV. In both full-scale and sled tests, all surrogates surpassing the HIC15 IARV also exceeded the cervical tension IARV. Positive linear correlations were observed between HIC15 and cervical tensile forces in both full-scale vehicle (R2 = 0.15) and sled testing runs (R2 = 0.54). CONCLUSIONS: These data support the hypothesis that inertial loading of the head provides a greater injury risk to the cervical spine than to closed-head injury.

Price Transparency in Neurosurgery: Challenges and Opportunities in the Online Publishing of Treatment Prices to Enable Cost-Conscious and Value-Based Practice.

OBJECTIVE: There is a paucity of evidence describing the price information that is publicly available to patients wishing to undergo neurosurgical procedures. We sought to investigate the public availability and usefulness of price estimates for non-emergent, elective neurosurgical interventions. METHODS: Google was used to search for price information related to 15 procedures in 8 major U.S. health care markets. We recorded price information that was published for each procedure and took note of whether itemized prices, potential discounts, and cross-provider price comparisons were available. RESULTS: Online searches yielded 2356 websites, of which 228 (9.7%) offered geographically relevant price information for neurosurgical procedures. Although accounting for only 16.4% of total search results, price transparency websites provided most treatment price estimates (74.1% of all estimates), followed by clinical sites (19.3%), and other related sites (5.3%). The number of websites providing price information varied significantly by city and procedure. websites rarely divulged data sources, specified how prices were estimated, indicated how frequently price estimates were updated, offered itemized breakdowns of prices, or indicated whether price estimates encompassed the full spectrum of possible health care charges. CONCLUSIONS: Under 10% of websites queried yield geographically relevant price information for non-emergent neurosurgical imaging and operative procedures. Even when this information is publicly available, its usefulness to patients may be limited by various factors, including obscure data sources and methods, as well as sparse information on discounts and bundled price estimates. Inconsistent availability and clarity of price information likely impede patients' ability to discern expected costs of treatment and engage in cost-conscious, value-based neurosurgical decision-making.

A Retrospective Analysis of the L3-L4 Disc and Spinopelvic Parameters on Outcomes in Thoracolumbar Fusion: Was Art Steffee Right?

OBJECTIVE: To determine whether the L3-L4 disc angle may be a surrogate marker for global lumbar alignment in thoracolumbar fusion surgery and to explore the relationship between radiographic and patient-reported outcomes after thoracolumbar fusion surgery. METHODS: Retrospective chart review was conducted on patients who had undergone a lumbar fusion involving levels from T9 to pelvis. EuroQol-Five Dimension (EQ-5D-3L) scores and adverse events including adjacent-segment disease and degeneration, pseudoarthrosis, proximal junctional kyphosis, stenosis, and reoperation were collected. Pre- and postoperative spinopelvic parameters were measured on weight-bearing radiographs, with the L3-L4 disc angle of novel interest. Univariate logistic and linear regression were performed to assess the associations of radiographic parameters with adverse event incidence and improvement in EQ-5D-3L, respectively. RESULTS: In total, 182 patients met inclusion criteria. Univariable analysis revealed that increased magnitude of L3-L4 disc angle, anterior pelvic tilt, and pelvic incidence measures are associated with increased likelihood of developing postoperative adverse events. Conversely, increased lumbar lordosis demonstrated a decreased incidence of developing a postoperative adverse event. Linear regression showed that radiographic parameters did not significantly correlate with postoperative EQ-5D-3L scores, although scores were significantly improved postfusion in all dimensions except Self-Care (P = 0.51). CONCLUSIONS: L3-L4 disc angle magnitude may serve as a surrogate marker of global lumbar alignment. The degree of spinopelvic alignment did not correlate to improvement in EQ-5D-3L score in the present study, suggesting that quality of life metric change may not be a sensitive or specific marker of postfusion alignment.

Intradiscal vacuum phenomenon and spinal degeneration: a cross-sectional analysis of 219 subjects.

INTRODUCTION: Intradiscal vacuum phenomenon (IVP) is the collection of gas within the intervertebral discs. It has been reported with various spinal disorders. The exact role of IVP in spinal degeneration leading to low back pain (LBP) is unclear. We aimed to obtain the prevalence of IVP in patients with LBP. Our second aim was to understand whether IVP was associated with intervertebral disc degeneration (IVDD), Modic changes, and subchondral sclerosis (SS). METHODS: A total of 12.450 consecutive patients with chronic LBP were evaluated in terms of having abdominal computed tomography (CT) scan concomitant with lumbar spine magnetic resonance imaging (MRI) using radiological database of three spine centers. We excluded the patients with a history of malignancy, metabolic disease, spinal infection, traumatic or osteoporotic spine fracture, and spine surgery. All lumbar levels were evaluated in terms of IVDD and Modic changes on MRI, while they were evaluated in terms of IVP and SS on CT scans. RESULTS: We included 219 patients. Severe IVDD, Modic changes, IVP, and SS were seen in 53.9% (n: 118), 38.8% (n: 85), 26.5% (n: 58), and 16% (n: 35) of the patients, respectively. Intradiscal vacuum phenomenon was closely associated with severe IVDD (OR: 8.204), Modic changes (OR: 3.547) and SS (OR: 4.231). DISCUSSION: Intradiscal vacuum phenomenon was closely associated with severe IVDD, Modic changes, and SS. Further prospective clinical and laboratory studies are necessary to better delineate the pathogenesis of IVP.

Postlaminectomy lumbopelvic sagittal changes in patients with developmental lumbar spinal stenosis grouped into Roussouly lumbopelvic sagittal profiles: 2- to 10-year prospective follow-up.

OBJECTIVE: Roussouly lumbopelvic sagittal profiles are associated with distinct pathologies or distinct natural histories and prognoses. The associations between developmental lumbar spinal stenosis (DLSS) and native lumbopelvic sagittal profiles are unknown. Moreover, the relative effects of multilevel decompression on lumbar sagittal alignment, geometrical parameters of the pelvis, and compensatory mechanisms for each of the Roussouly subtypes are unknown. This study aimed to explore the association between DLSS and native lumbar lordosis (LL) subtypes. It also attempts to understand the natural history of postlaminectomy lumbopelvic sagittal changes and compensatory mechanisms for each of the Roussouly subtypes and to define the critical lumbar segment or specific lordosis arc that is recruited after relief of the stenosis effect. METHODS: A total of 418 patients with multilevel DLSS were grouped into various Roussouly subtypes, and lumbopelvic sagittal parameters were prospectively compared at follow-up intervals of preoperative to < 2 years, 2 to < 5 years, and 5 to ≥ 10 years after laminectomy. The variables analyzed included LL, upper lordosis arc from L1 to L4, lower lordosis arc from L4 to S1, and segmental lordosis from L1 to S1. Pelvic parameters included pelvic incidence, sacral slope, pelvic tilt, and pelvic incidence minus LL values. RESULTS: Of the 329 patients who were followed up throughout this study, 33.7% had Roussouly type 1 native lordosis, whereas the incidence rates of types 2, 3, and 4 were 33.4%, 21.9%, and 10.9%, respectively. LL was not reduced in any of the Roussouly subtypes after multilevel decompressions. Instead, LL increased by 4.5° (SD 11.9°-from 27.3° [SD 11.5°] to 31.8° [SD 9.8°]) in Roussouly type 1 and by 3.1° (SD 11.6°-from 41.3° [SD 9.5°] to 44.4° [SD = 9.7°]) in Roussouly type 2. The other Roussouly types showed no significant changes. Pelvic tilt decreased significantly-by 2.8°, whereas sacral slope increased significantly-by 2.9° in Roussouly type 1 and by 1.7° in Roussouly type 2. The critical lumbar segment that recruits LL differs between Roussouly subtypes. Increments and changes were sustained until the final follow-up. CONCLUSIONS: The study findings are important in predicting patient prognosis, LL evolution, and the need for prophylactic or corrective deformity surgery. Multilevel involvement in DLSS and the high prevalence of Roussouly types 1 and 2 suggest that spinal canal dimensions are closely linked to the developmental evolution of LL.

Evaluating stability of the craniovertebral junction after unilateral C1 lateral mass resection: implications for the direct lateral approach.

OBJECTIVE: The direct lateral approach is an alternative to the transoral or endonasal approaches to ventral epidural lesions at the lower craniocervical junction. In this study, the authors performed, to their knowledge, the first in vitro biomechanical evaluation of the craniovertebral junction after sequential unilateral C1 lateral mass resection. The authors hypothesized that partial resection of the lateral mass would not result in a significant increase in range of motion (ROM) and may not require internal stabilization. METHODS: The authors performed multidirectional in vitro ROM testing using a robotic spine testing system on 8 fresh cadaveric specimens. We evaluated ROM in 3 primary movements (axial rotation [AR], flexion/extension [FE], and lateral bending [LB]) and 4 coupled movements (AR+E, AR+F, LB + left AR, and LB + right AR). Testing was performed in the intact state, after C1 hemilaminectomy, and after sequential 25%, 50%, 75%, and 100% C1 lateral mass resection. RESULTS: There were no significant increases in occipital bone (Oc)-C1, C1-2, or Oc-C2 ROM after C1 hemilaminectomy and 25% lateral mass resection. After 50% resection, Oc-C1 AR ROM increased by 54.4% (p = 0.002), Oc LB ROM increased by 47.8% (p = 0.010), and Oc-C1 AR+E ROM increased by 65.8% (p < 0.001). Oc-C2 FE ROM increased by 7.2% (p = 0.016) after 50% resection; 75% and 100% lateral mass resection resulted in further increases in ROM. CONCLUSIONS: In this cadaveric biomechanical study, the authors found that unilateral C1 hemilaminectomy and 25% resection of the C1 lateral mass did not result in significant biomechanical instability at the occipitocervical junction, and 50% resection led to significant increases in Oc-C2 ROM. This is the first biomechanical study of lateral mass resection, and future studies can serve to validate these findings.

Could gas-filled pseudocyst mimick extruded disc herniation?

There are case reports and small case series in the literature reporting gas-filled pseudocysts (GFP). However, a systematic review presenting overall view of the disease and its management is still lacking. In the present study, we aimed to make a systematic review of GFP cases, and present an exemplary case of ours. Our second aim was to discuss current theories for pathogenesis of GFP. A systematic review of GFP was conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline. Two large-scaled data search engines were used. A total of 53 articles were retrieved from the literature and presented with an exemplary case of ours. Mean age of the historical cohort was 59.47 years. There were 66 male (54.1%) and 56 female (45.9%) patients. The most prevalent clinical presentation was radicular sign/symptom in lower limbs with (29.1%) or without low back pain (LBP) (67%). Gas-filled pseudocyst has most commonly been diagnosed at the lower lumbar spine (L4-L5, 45.3%; L5-S1, 37.7%). Surgery was the treatment of choice in most of the patients (80%). In the whole cohort, 79.1% of the patients had complete recovery. Gas-filled pseudocysts are rarely observed in daily practice. They present mostly in men at the age of 60s. Precise differential diagnosis determination using appropriate imaging would help clinicians treat the patients properly. Gas-filled pseudocysts should be treated similarly to other spinal pathologies causing nerve root compression.

The change in postoperative opioid prescribing after lumbar decompression surgery following state-level opioid prescribing reform.

OBJECTIVE: On August 31, 2017, the state of Ohio implemented legislation limiting the dosage and duration of opioid prescriptions. Despite the widespread adoption of such restrictions, few studies have investigated the effects of these reforms on opioid prescribing and patient outcomes. In the present study, the authors aimed to evaluate the effect of recent state-level reform on opioid prescribing, patient-reported outcomes (PROs), and postoperative emergency department (ED) visits and hospital readmissions after elective lumbar decompression surgery. METHODS: This study was a retrospective cohort study of patients who underwent elective lumbar laminectomy for degenerative disease at one of 5 hospitals within a single health system in the years prior to and after the implementation of the statewide reform (September 1, 2016-August 31, 2018). Patients were classified according to the timing of their surgery relative to implementation of the prescribing reform: before reform (September 1, 2016-August 31, 2017) or after reform (September 1, 2017- August 31, 2018). The outcomes of interest included total outpatient opioids prescribed in the 90 days following discharge from surgery as measured in morphine-equivalent doses (MEDs), total number of opioid refill prescriptions written, patient-reported pain at the first postoperative outpatient visit as measured by the Numeric Pain Rating Scale, improvement in patient-reported health-related quality of life as measured by the Patient-Reported Outcomes Measurement Information System-Global Health (PROMIS-GH) questionnaire, and ED visits or hospital readmissions within 90 days of surgery. RESULTS: A total of 1031 patients met the inclusion criteria for the study, with 469 and 562 in the before- and after-reform groups, respectively. After-reform patients received 26% (95% CI 19%-32%) fewer MEDs in the 90 days following discharge compared with the before-reform patients. No significant differences were observed in the overall number of opioid prescriptions written, PROs, or postoperative ED or hospital readmissions within 90 days in the year after the implementation of the prescribing reform. CONCLUSIONS: Patients undergoing surgery in the year after the implementation of a state-level opioid prescribing reform received significantly fewer MEDs while reporting no change in the total number of opioid prescriptions, PROs, or postoperative ED visits or hospital readmissions. These results demonstrate that state-level reforms placing reasonable limits on opioid prescriptions written for acute pain may decrease patient opioid exposure without negatively impacting patient outcomes after lumbar decompression surgery.

Global Sagittal Balance of Spine in Asymptomatic Controls: A Systematic Review and Meta-Analysis.

OBJECTIVE: To assess the global sagittal balance of spine (GSBS) in asymptomatic controls. METHODS: PubMed, Scopus, Cochrane library, and Web of Science searched up to July 2020. Studies were screened for the GSB parameters including T1 pelvic angle (TPA), spinosacral angle (SSA), sagittal vertical axis (SVA), C7/sacrofemoral distance ratio (Barrey index), odontoid hip axis (OD-HA), and Full Balance Index (FBI) as measured in asymptomatic participants. A meta-analysis was performed to synthesize pooled estimates. Heterogeneity and publication bias were assessed. RESULTS: Overall, 76 studies were identified including 12,169 participants (54.7% female) with mean age ranges from 12.0 to 72.9 years old. We used the Newcastle-Ottawa Scale (NOS) to evaluate the quality of studies included in this review. Begg's test did not indicate obvious publication bias. The pooled analysis reveals that the mean (standard deviation) normative values were: 1) age ˃18 years, SSA (°), 127.6 (0.89); SVA absolute value (millimeters), 13.1 (1.13); TPA (°), 9.8 (1.13); T1SPI (°), -4.3 (0.57); and Barrey index absolute value, 0.51 (0.3). The mean value of the OD-HA (°) was reported 2.9 (1.6), and the FBI average value was less than 5°. 2) Age ≤18 years, SSA (°), 132.1 (8.3); SVA absolute value (millimeters), 11.9 (2.0); and Barrey index, -0.7 (8.3). A significant difference was observed between the 2 age groups based on SVA and SSA. CONCLUSIONS: This paper presents normative data on TPA, SSA, SVA, Barrey index, OD-HA, and FBI as a reference for evaluating/measuring a GSB of spine in asymptomatic controls.