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1.
Neurosurg Focus ; 55(1): E5, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37392770

RESUMEN

OBJECTIVE: The incidence of sacroiliac joint (SIJ) dysfunction after lumbosacral fusion is high. Upfront bilateral SIJ fusion using novel fenestrated self-harvesting porous S2-alar iliac (S2AI) screws could reduce the incidence of SIJ dysfunction and need for subsequent SIJ fusion. In this study, the authors report their early clinical and radiographic results of SIJ fusion using this novel screw. METHODS: The authors began using self-harvesting porous screws in July 2022. This is a retrospective review of consecutive patients at a single institution who underwent long thoracolumbar surgery with extension to the pelvis using this porous screw. Radiographic parameters of regional and global alignment were collected preoperatively and at the time of last follow-up. The incidence of intraoperative complications and need for revision were collected. The incidences of mechanical complications, including screw breakage, implant loosening/pullout, and screw cap dislocation at the time of last follow-up were also collected. RESULTS: Ten patients with a mean age of 67 years were included, 6 of whom were male. Seven patients had a thoracolumbar construct with extension to the pelvis. Three patients had upper instrumented vertebrae at the proximal lumbar spine. Intraoperative breach was not encountered in any of the patients (0%). Postoperatively, 1 patient (10%) had screw breakage at the neck of the tulip of the modified iliac screw discovered at routine follow-up without clinical sequalae. CONCLUSIONS: Use of self-harvesting porous S2AI screws incorporated into long thoracolumbar constructs was safe and feasible, demanding unique technical considerations. Long-term clinical and radiographic follow-up with a large patient cohort is necessary to determine their durability and efficacy to achieve SIJ arthrodesis and prevent SIJ dysfunction.


Asunto(s)
Enfermedades de la Columna Vertebral , Fusión Vertebral , Tulipa , Humanos , Masculino , Anciano , Femenino , Articulación Sacroiliaca/diagnóstico por imagen , Articulación Sacroiliaca/cirugía , Porosidad , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Tornillos Óseos
2.
Neurosurg Focus ; 55(3): E4, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37657109

RESUMEN

OBJECTIVE: Fusion rates and long-term outcomes are well established for anterior cervical discectomy and fusion (ACDF) of 3 levels or fewer, but there is a paucity of similar data on 4-level fusions. The authors evaluated long-term fusion rates and clinical outcomes after 4-level ACDF without supplemental posterior instrumentation. METHODS: The authors retrospectively reviewed patients who underwent 4-level ACDF at a single institution with at least 1-year of radiological follow-up. Fusion was determined by measuring change in interspinous distance at each segment on dynamic radiographs or by the presence of bridging bone on CT scans at minimum 1-year follow-up. Clinical outcomes were assessed using Neck Disability Index and Short Form-36. RESULTS: A total of 63 patients (252 levels) met the inclusion criteria for the study, with a mean follow-up of 2.6 years. Complete radiographic fusion at all 4 levels was observed in 26 patients (41.3%). Of the 37 patients (58.7%) with radiographic pseudarthrosis, there was a mean of 1.35 nonfused levels. The fusion rate per level, however, was 80.2% (202/252 levels). The most common level demonstrating nonunion was the distal segment (C6-7), showing pseudarthrosis in 29 patients (46.8%), followed by the most proximal segment (C3-4) demonstrating nonunion in 9 patients (14.5%). The mean improvement in Neck Disability Index and Short Form-36 was 15.7 (p < 0.01) and 5.8 (p = 0.14), respectively, with improvement in both scores surpassing the minimum clinically important difference. One patient (1.6%) required revision surgery for symptomatic pseudarthrosis, and 5 patients (7.9%) underwent revision for symptomatic adjacent-segment disease. Patient-reported outcomes results are limited by the low rate of 1-year follow-up (50.8%), whereas reoperation data were available for all 63 patients. CONCLUSIONS: More than half of patients undergoing 4-level ACDF without posterior fixation demonstrated pseudarthrosis of at least 1 level-most commonly the distal C6-7 level. One patient required revision for symptomatic pseudarthrosis. Patient-reported outcomes showed significant improvements at 1-year follow-up, but clinical follow-up was limited. This is the largest series to date to evaluate fusion outcomes in 4-level ACDF.


Asunto(s)
Seudoartrosis , Humanos , Seudoartrosis/diagnóstico por imagen , Seudoartrosis/cirugía , Estudios Retrospectivos , Reoperación , Discectomía , Medición de Resultados Informados por el Paciente
3.
Neurosurg Focus ; 55(3): E2, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37657103

RESUMEN

OBJECTIVE: The authors sought to compare 3-level anterior with posterior fusion surgical procedures for the treatment of multilevel cervical spondylotic myelopathy (CSM). METHODS: The authors analyzed prospective data from the 14 highest enrolling sites of the Quality Outcomes Database CSM module. They compared 3-level anterior cervical discectomy and fusion (ACDF) and posterior cervical laminectomy and fusion (PCF) surgical procedures, excluding surgical procedures crossing the cervicothoracic junction. Rates of reaching the minimal clinically important difference (MCID) in patient-reported outcomes (PROs) were compared at 24 months postoperatively. Multivariable analyses adjusted for potential confounders elucidated in univariable analysis. RESULTS: Overall, 199 patients met the inclusion criteria: 123 ACDF (61.8%) and 76 PCF (38.2%) patients. The 24-month follow-up rates were similar (ACDF 90.2% vs PCF 92.1%, p = 0.67). Preoperatively, ACDF patients were younger (60.8 ± 10.2 vs 65.0 ± 10.3 years, p < 0.01), and greater proportions were privately insured (56.1% vs 36.8%, p = 0.02), actively employed (39.8% vs 22.8%, p = 0.04), and independently ambulatory (14.6% vs 31.6%, p < 0.01). Otherwise, the cohorts had equivalent baseline modified Japanese Orthopaedic Association (mJOA), Neck Disability Index (NDI), numeric rating scale (NRS)-arm pain, NRS-neck pain, and EQ-5D scores (p > 0.05). ACDF patients had reduced hospitalization length (1.6 vs 3.9 days, p < 0.01) and a greater proportion had nonroutine discharge (7.3% vs 22.8%, p < 0.01), but they had a higher rate of postoperative dysphagia (13.5% vs 3.5%, p = 0.049). Compared with baseline values, both groups demonstrated improvements in all outcomes at 24 months (p < 0.05). In multivariable analyses, after controlling for age, insurance payor, employment status, ambulation status, and other potential clinically relevant confounders, ACDF was associated with a greater proportion of patients with maximum satisfaction on the North American Spine Society Patient Satisfaction Index (NASS) (NASS score of 1) at 24 months (69.4% vs 53.7%, OR 2.44, 95% CI 1.17-5.09, adjusted p = 0.02). Otherwise, the cohorts shared similar 24-month outcomes in terms of reaching the MCID for mJOA, NDI, NRS-arm pain, NRS-neck pain, and EQ-5D score (adjusted p > 0.05). There were no differences in the 3-month readmission (ACDF 4.1% vs PCF 3.9%, p = 0.97) and 24-month reoperation (ACDF 13.5% vs PCF 18.6%, p = 0.36) rates. CONCLUSIONS: In a cohort limited to 3-level fusion surgical procedures, ACDF was associated with reduced blood loss, shorter hospitalization length, and higher routine home discharge rates; however, PCF resulted in lower rates of postoperative dysphagia. The procedures yielded comparably significant improvements in functional status (mJOA score), neck and arm pain, neck pain-related disability, and quality of life at 3, 12, and 24 months. ACDF patients had significantly higher odds of maximum satisfaction (NASS score 1). Given comparable outcomes, patients should be counseled on each approach's complication profile to aid in surgical decision-making.

4.
Neurosurg Focus ; 54(6): E5, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37283449

RESUMEN

OBJECTIVE: The purpose of this study was to evaluate the performance of different supervised machine learning algorithms to predict achievement of minimum clinically important difference (MCID) in neck pain after surgery in patients with cervical spondylotic myelopathy (CSM). METHODS: This was a retrospective analysis of the prospective Quality Outcomes Database CSM cohort. The data set was divided into an 80% training and a 20% test set. Various supervised learning algorithms (including logistic regression, support vector machine, decision tree, random forest, extra trees, gaussian naïve Bayes, k-nearest neighbors, multilayer perceptron, and extreme gradient boosted trees) were evaluated on their performance to predict achievement of MCID in neck pain at 3 and 24 months after surgery, given a set of predicting baseline features. Model performance was assessed with accuracy, F1 score, area under the receiver operating characteristic curve, precision, recall/sensitivity, and specificity. RESULTS: In total, 535 patients (46.9%) achieved MCID for neck pain at 3 months and 569 patients (49.9%) achieved it at 24 months. In each follow-up cohort, 501 patients (93.6%) were satisfied at 3 months after surgery and 569 patients (100%) were satisfied at 24 months after surgery. Of the supervised machine learning algorithms tested, logistic regression demonstrated the best accuracy (3 months: 0.76 ± 0.031, 24 months: 0.773 ± 0.044), followed by F1 score (3 months: 0.759 ± 0.019, 24 months: 0.777 ± 0.039) and area under the receiver operating characteristic curve (3 months: 0.762 ± 0.027, 24 months: 0.773 ± 0.043) at predicting achievement of MCID for neck pain at both follow-up time points, with fair performance. The best precision was also demonstrated by logistic regression at 3 (0.724 ± 0.058) and 24 (0.780 ± 0.097) months. The best recall/sensitivity was demonstrated by multilayer perceptron at 3 months (0.841 ± 0.094) and by extra trees at 24 months (0.817 ± 0.115). Highest specificity was shown by support vector machine at 3 months (0.952 ± 0.013) and by logistic regression at 24 months (0.747 ± 0.18). CONCLUSIONS: Appropriate selection of models for studies should be based on the strengths of each model and the aims of the studies. For maximally predicting true achievement of MCID in neck pain, of all the predictions in this balanced data set the appropriate metric for the authors' study was precision. For both short- and long-term follow-ups, logistic regression demonstrated the highest precision of all models tested. Logistic regression performed consistently the best of all models tested and remains a powerful model for clinical classification tasks.


Asunto(s)
Dolor de Cuello , Enfermedades de la Médula Espinal , Humanos , Estudios Retrospectivos , Estudios Prospectivos , Dolor de Cuello/diagnóstico , Dolor de Cuello/cirugía , Teorema de Bayes , Aprendizaje Automático Supervisado , Algoritmos , Enfermedades de la Médula Espinal/cirugía
5.
Neurosurg Focus ; 55(5): E7, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37913530

RESUMEN

OBJECTIVE: There is a high prevalence of cervical myelopathy that requires surgery; as such, it is important to identify how different groups benefit from surgery. The American Association of Neurological Surgeons launched the Quality Outcomes Database (QOD), a prospective longitudinal registry, that includes demographic, clinical, and patient-reported outcome data to measure the safety and quality of neurosurgical procedures. In this study, the authors assessed the impact of gender on patient-reported outcomes in patients who underwent surgery for cervical myelopathy. METHODS: The authors analyzed 1152 patients who underwent surgery for cervical myelopathy and were included in the QOD cervical module. Univariate comparison of baseline patient characteristics between males and females who underwent surgery for cervical spondylotic myelopathy was performed. Baseline characteristics that significantly differed between males and females were included in a multivariate generalized linear model comparing baseline and 1-year postoperative Neck Disability Index (NDI) scores. RESULTS: This study included 546 females and 604 males. Females demonstrated significantly greater improvement in NDI score 1 year after surgery (p = 0.036). In addition to gender, the presence of axial neck pain and insurance status were also significantly predictive of improvement in NDI score after surgery (p = 0.0013 and p = 0.0058, respectively). CONCLUSIONS: Females were more likely to benefit from surgery for cervical myelopathy compared with males. It is important to identify gender differences in postoperative outcomes after surgery in order to deliver more personalized and patient-centric care.


Asunto(s)
Cuello , Enfermedades de la Médula Espinal , Masculino , Humanos , Femenino , Estudios Prospectivos , Vértebras Cervicales/cirugía , Dolor de Cuello , Enfermedades de la Médula Espinal/cirugía , Resultado del Tratamiento
6.
BMC Pediatr ; 22(1): 54, 2022 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-35062907

RESUMEN

BACKGROUND: Poor child growth and development outcomes stem from complex relationships encompassing biological, behavioral, social, and environmental conditions. However, there is a dearth of research on integrated approaches targeting these interwoven factors. The Grandi Byen study seeks to fill this research gap through a three-arm longitudinal randomized controlled trial which will evaluate the impact of an integrated nutrition, responsive parenting, and WASH (water, sanitation and hygiene) intervention on holistic child growth and development. METHODS: We will recruit 600 mother-infant dyads living in Cap-Haitien, Haiti and randomize them equally into one of the following groups: 1) standard well-baby care; 2) nutritional intervention (one egg per day for 6 months); and 3) multicomponent Grandi Byen intervention (responsive parenting, nutrition, WASH + one egg per day for 6 months). Primary outcomes include child growth as well as cognitive, language, motor, and social-emotional development. The study also assesses other indicators of child health (bone maturation, brain growth, diarrheal morbidity and allergies, dietary intake, nutrient biomarkers) along with responsive parenting as mediating factors influencing the primary outcomes. An economic evaluation will assess the feasibility of large-scale implementation of the interventions. DISCUSSION: This study builds on research highlighting the importance of responsive parenting interventions on overall child health, as well as evidence demonstrating that providing an egg daily to infants during the complementary feeding period can prevent stunted growth. The multicomponent Grandi Byen intervention may provide evidence of synergistic or mediating effects of an egg intervention with instruction on psychoeducational parenting and WASH on child growth and development. Grandi Byen presents key innovations with implications for the well-being of children living in poverty globally. TRIAL REGISTRATION: NCT04785352 . Registered March 5, 2021 at https://clinicaltrials.gov/.


Asunto(s)
Higiene , Responsabilidad Parental , Niño , Desarrollo Infantil , Crecimiento y Desarrollo , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Ensayos Clínicos Controlados Aleatorios como Asunto , Saneamiento
7.
Eur Spine J ; 31(9): 2239-2247, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35524824

RESUMEN

PURPOSE: To describe a comprehensive setting of the different alternatives for performing a single position fusion surgery based on the opinion of leading surgeons in the field. METHODS: Between April and May of 2021, a specifically designed two round survey was distributed by mail to a group of leaders in the field of Single Position Surgery (SPS). The questionnaire included a variety of domains which were focused on highlighting tips and recommendations regarding improving the efficiency of the performance of SPS. This includes operation room setting, positioning, use of technology, approach, retractors specific details, intraoperative neuromonitoring and tips for inserting percutaneous pedicle screws in the lateral position. It asked questions focused on Lateral Single Position Surgery (LSPS), Lateral ALIF (LA) and Prone Lateral Surgery (PLS). Strong agreement was defined as an agreement of more than 80% of surgeons for each specific question. The number of surgeries performed in SPS by each surgeon was used as an indirect element to aid in exhibiting the expertise of the surgeons being surveyed. RESULTS: Twenty-four surgeons completed both rounds of the questionnaire. Moderate or strong agreement was found for more than 50% of the items. A definition for Single Position Surgery and a step-by-step recommendation workflow was built to create a better understanding of surgeons who are starting the learning curve in this technique. CONCLUSION: A recommendation of the setting for performing single position fusion surgery procedure (LSPS, LA and PLS) was developed based on a survey of leaders in the field.


Asunto(s)
Tornillos Pediculares , Fusión Vertebral , Cirujanos , Humanos , Vértebras Lumbares/cirugía , Fusión Vertebral/métodos , Encuestas y Cuestionarios
8.
Circulation ; 142(23): e432-e447, 2020 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-33147996

RESUMEN

In 2010, the American Heart Association published a statement concluding that the existing scientific evidence was consistent with a causal relationship between exposure to fine particulate matter and cardiovascular morbidity and mortality, and that fine particulate matter exposure is a modifiable cardiovascular risk factor. Since the publication of that statement, evidence linking air pollution exposure to cardiovascular health has continued to accumulate and the biological processes underlying these effects have become better understood. This increasingly persuasive evidence necessitates policies to reduce harmful exposures and the need to act even as the scientific evidence base continues to evolve. Policy options to mitigate the adverse health impacts of air pollutants must include the reduction of emissions through action on air quality, vehicle emissions, and renewable portfolio standards, taking into account racial, ethnic, and economic inequality in air pollutant exposure. Policy interventions to improve air quality can also be in alignment with policies that benefit community and transportation infrastructure, sustainable food systems, reduction in climate forcing agents, and reduction in wildfires. The health care sector has a leadership role in adopting policies to contribute to improved environmental air quality as well. There is also potentially significant private sector leadership and industry innovation occurring in the absence of and in addition to public policy action, demonstrating the important role of public-private partnerships. In addition to supporting education and research in this area, the American Heart Association has an important leadership role to encourage and support public policies, private sector innovation, and public-private partnerships to reduce the adverse impact of air pollution on current and future cardiovascular health in the United States.


Asunto(s)
Contaminación del Aire/efectos adversos , Contaminación del Aire/prevención & control , American Heart Association , Enfermedades Cardiovasculares/prevención & control , Guías de Práctica Clínica como Asunto/normas , Política Pública , Contaminantes Atmosféricos/efectos adversos , Enfermedades Cardiovasculares/epidemiología , Disparidades en Atención de Salud , Humanos , Material Particulado/efectos adversos , Estados Unidos/epidemiología
9.
Environ Health ; 20(1): 27, 2021 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-33722243

RESUMEN

BACKGROUND: Exposure to occupational manganese (Mn) is associated with neurotoxic brain injury, manifesting primarily as parkinsonism. The association between environmental Mn exposure and parkinsonism is unclear. To characterize the association between environmental Mn exposure and parkinsonism, we performed population-based sampling of residents older than 40 in Meyerton, South Africa (N = 621) in residential settlements adjacent to a large Mn smelter and in a comparable non-exposed settlement in Ethembalethu, South Africa (N = 95) in 2016-2020. METHODS: A movement disorders specialist examined all participants using the Unified Parkinson Disease Rating Scale motor subsection part 3 (UPDRS3). Participants also completed an accelerometry-based kinematic test and a grooved pegboard test. We compared performance on the UPDRS3, grooved pegboard, and the accelerometry-based kinematic test between the settlements using linear regression, adjusting for covariates. We also measured airborne PM2.5-Mn in the study settlements. RESULTS: Mean PM2.5-Mn concentration at a long-term fixed site in Meyerton was 203 ng/m3 in 2016-2017 - approximately double that measured at two other neighborhoods in Meyerton. The mean Mn concentration in Ethembalethu was ~ 20 times lower than that of the long-term Meyerton site. UPDRS3 scores were 6.6 (CI 5.2, 7.9) points higher in Meyerton than Ethembalethu residents. Mean angular velocity for finger-tapping on the accelerometry-based kinematic test was slower in Meyerton than Ethembalethu residents [dominant hand 74.9 (CI 48.7, 101.2) and non-dominant hand 82.6 (CI 55.2, 110.1) degrees/second slower]. Similarly, Meyerton residents took longer to complete the grooved pegboard, especially for the non-dominant hand (6.9, CI -2.6, 16.3 s longer). CONCLUSIONS: Environmental airborne Mn exposures at levels substantially lower than current occupational exposure thresholds in the United States may be associated with clinical parkinsonism.


Asunto(s)
Contaminantes Ocupacionales del Aire/toxicidad , Exposición a Riesgos Ambientales/efectos adversos , Manganeso/toxicidad , Trastornos Parkinsonianos/inducido químicamente , Acelerometría , Adolescente , Adulto , Anciano , Contaminantes Ocupacionales del Aire/análisis , Fenómenos Biomecánicos , Niño , Preescolar , Exposición a Riesgos Ambientales/análisis , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Manganeso/análisis , Pruebas de Estado Mental y Demencia , Metalurgia , Persona de Mediana Edad , Trastornos Parkinsonianos/fisiopatología , Material Particulado/análisis , Material Particulado/toxicidad , Sudáfrica , Adulto Joven
10.
Neurosurg Focus ; 49(3): E15, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32871564

RESUMEN

OBJECTIVE: Lateral lumbar interbody fusion (LLIF) is a useful minimally invasive technique for achieving anterior interbody fusion and preserving or restoring lumbar lordosis. However, achieving circumferential fusion via posterior instrumentation after an LLIF can be challenging, requiring either repositioning the patient or placing pedicle screws in the lateral position. Here, the authors explore an alternative single-position approach: LLIF in the prone lateral (PL) position. METHODS: A cadaveric feasibility study was performed using 2 human cadaveric specimens. A retrospective 2-center early clinical series was performed for patients who had undergone a minimally invasive lateral procedure in the prone position between August 2019 and March 2020. Case duration, retractor time, electrophysiological thresholds, implant size, screw accuracy, and complications were recorded. Early postoperative radiographic outcomes were reported. RESULTS: A PL LLIF was successfully performed in 2 cadavers without causing injury to a vessel or the bowel. No intraoperative subsidence was observed. In the clinical series, 12 patients underwent attempted PL surgery, although 1 case was converted to standard lateral positioning. Thus, 11 patients successfully underwent PL LLIF (89%) across 14 levels: L2-3 (2 of 14 [14%]), L3-4 (6 of 14 [43%]), and L4-5 (6 of 14 [43%]). For the 11 PL patients, the mean (± SD) age was 61 ± 16 years, mean BMI was 25.8 ± 4.8, and mean retractor time per level was 15 ± 6 minutes with the longest retractor time at L2-3 and the shortest at L4-5. No intraoperative subsidence was noted on routine postoperative imaging. CONCLUSIONS: Performing single-position lateral transpsoas interbody fusion with the patient prone is anatomically feasible, and in an early clinical experience, it appeared safe and reproducible. Prone positioning for a lateral approach presents an exciting opportunity for streamlining surgical access to the lumbar spine and facilitating more efficient surgical solutions with potential clinical and economic advantages.


Asunto(s)
Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Posicionamiento del Paciente/métodos , Posición Prona , Fusión Vertebral/métodos , Adulto , Anciano , Cadáver , Estudios de Factibilidad , Femenino , Humanos , Dolor de la Región Lumbar/diagnóstico por imagen , Dolor de la Región Lumbar/cirugía , Vértebras Lumbares/patología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
12.
Clin Anat ; 32(3): 348-353, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30471151

RESUMEN

Anterior column release is a powerful surgical technique for achieving spinopelvic balance in adult patients with sagittal plane deformities. We present an alternative strategy for focal deformity correction from a posterior-only approach. The purpose of this study was to evaluate the feasibility and efficacy of a novel surgical technique called posterior open-wedge diskectomy and anterior longitudinal ligament (ALL) release (POWAR). A cadaveric torso underwent POWARs at the L1-L4 intervertebral disc spaces. Baseline measurements of end-plate angle (EPA), anterior intervertebral disc height (ADH), and posterior intervertebral disc height (PDH) were obtained. These measurements were repeated after three stages of correction: posterior column compression alone, posterior column compression following Schwab grade 2 osteotomies, and posterior column compression following POWAR. A second cadaver underwent posterolateral spinal dissection to demonstrate the pertinent anatomical features relevant to this novel procedure. With each stage of correction, a sequential increase in EPA and ADH and a decrease in PDH were demonstrated. The large increase in ADH seen following POWAR confirmed successful release of the ALL. In situ investigation of the aorta and inferior vena cava following anterior exposure revealed no injury to the great vessels or surrounding structures. Ex vivo testing of the aorta and inferior vena cava took place at the L3-4 level. This testing demonstrated no injury or tears to either vessel. POWAR is a new surgical technique that can provide an alternative to three-column osteotomy for surgeons performing spinal reconstructions in adults through an open, posterior-only approach. Clin. Anat. 32:348-353, 2019. © 2018 Wiley Periodicals, Inc.


Asunto(s)
Descompresión Quirúrgica/métodos , Discectomía/métodos , Ligamentos Longitudinales/cirugía , Vértebras Lumbares/anomalías , Adulto , Cadáver , Estudios de Factibilidad , Humanos , Vértebras Lumbares/cirugía , Fusión Vertebral/métodos
13.
Proc Natl Acad Sci U S A ; 111(9): 3484-9, 2014 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-24567398

RESUMEN

Determining how widespread human-induced changes such as habitat loss, landscape fragmentation, and climate instability affect populations, communities, and ecosystems is one of the most pressing environmental challenges. Critical to this challenge is understanding how these changes are affecting the movement abilities and dispersal trajectories of organisms and what role conservation planning can play in promoting movement among remaining fragments of suitable habitat. Whereas evidence is mounting for how conservation strategies such as corridors impact animal movement, virtually nothing is known for species dispersed by wind, which are often mistakenly assumed to not be limited by dispersal. Here, we combine mechanistic dispersal models, wind measurements, and seed releases in a large-scale experimental landscape to show that habitat corridors affect wind dynamics and seed dispersal by redirecting and bellowing airflow and by increasing the likelihood of seed uplift. Wind direction interacts with landscape orientation to determine when corridors provide connectivity. Our results predict positive impacts of connectivity and patch shape on species richness of wind-dispersed plants, which we empirically illustrate using 12 y of data from our experimental landscapes. We conclude that habitat fragmentation and corridors strongly impact the movement of wind-dispersed species, which has community-level consequences.


Asunto(s)
Biodiversidad , Ecosistema , Modelos Biológicos , Fenómenos Fisiológicos de las Plantas/fisiología , Dispersión de Semillas/fisiología , Viento , Geografía
14.
Environ Sci Technol ; 50(8): 4335-42, 2016 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-27010702

RESUMEN

Isoprene is the predominant non-methane volatile organic compound emitted to the atmosphere and shapes tropospheric composition and biogeochemistry through its effects on ozone, other oxidants, aerosols, and the nitrogen cycle. Isoprene is emitted naturally by vegetation during daytime, when its photo-oxidation is rapid, and in the presence of nitrogen oxides (NOx) produces ozone and degrades air quality in polluted regions. Here, we show for a city downwind of an isoprene-emitting forest (St. Louis, MO) that isoprene actually peaks at night; ambient levels then endure, owing to low nighttime OH radical concentrations. Nocturnal chemistry controls the fate of that isoprene and the likelihood of a high-ozone episode the following day. When nitrate (NO3) radicals are suppressed, high isoprene persists through the night, providing photochemical fuel upon daybreak and leading to a dramatic late-morning ozone peak. On nights with significant NO3, isoprene is removed before dawn; days with low morning isoprene then have lower ozone with a more typical afternoon peak. This biogenic-anthropogenic coupling expands the daily high-ozone window and likely has an opposite O3-NOx response to what would otherwise be expected, with implications for exposure and air-quality management in cities that, like St. Louis, are downwind of major isoprene-emitting forests.


Asunto(s)
Contaminantes Atmosféricos/química , Aire , Butadienos/química , Bosques , Hemiterpenos/química , Ozono/química , Pentanos/química , Aerosoles/química , Contaminantes Atmosféricos/análisis , Atmósfera/química , Butadienos/análisis , Ciudades , Hemiterpenos/análisis , Illinois , Nitratos/química , Óxidos de Nitrógeno/análisis , Ozono/análisis , Pentanos/análisis , Compuestos Orgánicos Volátiles , Viento
15.
Neurosurg Focus ; 40(3): E11, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26926051

RESUMEN

OBJECTIVE: This study evaluated the utility, specificity, and sensitivity of intraoperative confocal laser endomicroscopy (CLE) to provide diagnostic information during resection of human brain tumors. METHODS: CLE imaging was used in the resection of intracranial neoplasms in 74 consecutive patients (31 male; mean age 47.5 years; sequential 10-month study period). Intraoperative in vivo and ex vivo CLE was performed after intravenous injection of fluorescein sodium (FNa). Tissue samples from CLE imaging-matched areas were acquired for comparison with routine histological analysis (frozen and permanent sections). CLE images were classified as diagnostic or nondiagnostic. The specificities and sensitivities of CLE and frozen sections for gliomas and meningiomas were calculated using permanent histological sections as the standard. RESULTS: CLE images were obtained for each patient. The mean duration of intraoperative CLE system use was 15.7 minutes (range 3-73 minutes). A total of 20,734 CLE images were correlated with 267 biopsy specimens (mean number of images/biopsy location, in vivo 84, ex vivo 70). CLE images were diagnostic for 45.98% in vivo and 52.97% ex vivo specimens. After initiation of CLE, an average of 14 in vivo images and 7 ex vivo images were acquired before identification of a first diagnostic image. CLE specificity and sensitivity were, respectively, 94% and 91% for gliomas and 93% and 97% for meningiomas. CONCLUSIONS: CLE with FNa provided intraoperative histological information during brain tumor removal. Specificities and sensitivities of CLE for gliomas and meningiomas were comparable to those for frozen sections. These data suggest that CLE could allow the interactive identification of tumor areas, substantially improving intraoperative decisions during the resection of brain tumors.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/cirugía , Fluoresceína , Colorantes Fluorescentes , Monitoreo Intraoperatorio/métodos , Monitoreo Intraoperatorio/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Fluoresceína/administración & dosificación , Colorantes Fluorescentes/administración & dosificación , Humanos , Masculino , Microscopía Confocal/métodos , Microscopía Confocal/estadística & datos numéricos , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
16.
Eur Spine J ; 24 Suppl 3: 427-32, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25820352

RESUMEN

PURPOSE: Anterior column reconstruction (ACR) is a minimally invasive technique for the treatment of sagittal plane deformity. ACR uses a lateral transpsoas approach with ALL release and the application of an interbody device to achieve correction. Here, we present 1-year radiographic results from a multicenter study of adult spinal deformity (ASD) patients. METHODS: A multicenter database was queried from 2005 to 2013 for ASD patients treated with ACR. Demographics, surgical data, and radiographic measurements were collected and retrospectively analyzed. Radiographic time points included preoperative (pre-op), postoperative (post-op; first visit prior to 3 months), and last follow-up (last FU; minimum of 1 year). Sagittal radiographic measurements included regional lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), T1 spinopelvic inclination (T1SPi), and segmental lordosis (disc angle). RESULTS: Mean patient age was 67.4 years (range 46.5-80.0) and 11 patients (32.4 %) were male. Twenty patients (58.8 %) had previous lumbar surgery. All patients had a minimal of one-level ACR with ALL release (mean 1.7; range 1-4). Mean number of lateral interbody fusion (LLIF) levels without ALL release per patient was 0.7 (range 0-3). Thirty-three patients (97.1 %) received supplemental posterior fixation and 1 patient (2.9 %) had lateral fixation only. In 26 patients (76.5 %), supplemental posterior fixation was performed using an open approach, and 7 patients (20.6 %) were treated with percutaneous placement. Mean of number of levels fused was 7.1 (range 2-16). There was a significant improvement in LL (p < 0.001), PI-LL mismatch (p < 0.001), and PT (p = 0.03) from pre-op to post-op, and pre-op to last FU. There was no change in T1SPi, SS, or PI. Segmental lordosis improved at ACR levels from mean of -2.2° pre-op to -16.0° post-op (p < 0.01) and -16.3° at last FU (p < 0.001). The addition of posterior column osteotomy increased the change in segmental lordosis with ACR by 72.7 % (p < 0.001). LLIF without ALL release led to significant improvement in segmental lordosis from pre-op (-2.4°) to post-op (-7.1°; p < 0.01) but not from pre-op to last FU (-5.7°; p = 0.06). CONCLUSION: ACR successfully restores lumbar lordosis in ASD patients with sagittal imbalance. ACR results in greater segmental correction than is achieved with LLIF alone. Supplementing with posterior osteotomies allows for even greater correction. The ability to achieve the desired radiographic goals is expected to improve as technical nuances are refined and patient selection is optimized.


Asunto(s)
Lordosis/cirugía , Vértebras Lumbares/cirugía , Fusión Vertebral/métodos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Lordosis/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Osteotomía/métodos , Pelvis/diagnóstico por imagen , Pelvis/patología , Radiografía , Procedimientos de Cirugía Plástica/métodos , Estudios Retrospectivos
17.
World Neurosurg ; 183: 192-203, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37995989

RESUMEN

BACKGROUND: Osseous spinal metastases from intracranial meningiomas are rare but represent a serious disease progression. A literature review was performed on this topic to understand the clinical course of patients with this disease entity. We also present a case of spinal metastasis in a patient with a World Health Organization grade III meningioma. METHODS: The PubMed/MEDLINE database was queried on August 15, 2021, using the keywords (meningioma) AND (metastasis) AND (vertebra∗ OR spin∗). All publications reporting outcomes of patients with meningioma metastatic to the spine were included. Disease characteristics, treatment modality, and outcomes were extracted from each study. Because data availability varied widely between studies, no meta-analysis was performed. RESULTS: A total of 30 articles with 33 cases were included. Outcome data varied greatly in terms of quality and length of follow-up. Of 28 cases with reported outcomes data, 20 resulted in patient mortality ranging from a few weeks to 5 years after spinal metastasis. Mean (standard deviation) survival time was 5.8 (6.4) years following initial diagnosis, but only 1.4 (3.2) years from spinal metastasis. The longest survivor was noted to have no recurrence of disease 4 years after spinal metastasis. CONCLUSIONS: Bony spinal metastasis from intracranial meningioma is an extremely rare occurrence. Within the limits of the available literature, outcomes of patients with this disease appear to be poor. However, data reporting is inconsistent, and several articles did not report any outcome data. Further study is needed to better clarify the course and prognosis of this disease.


Asunto(s)
Neoplasias Meníngeas , Meningioma , Neoplasias de la Columna Vertebral , Humanos , Meningioma/diagnóstico por imagen , Meningioma/cirugía , Neoplasias de la Columna Vertebral/diagnóstico por imagen , Neoplasias de la Columna Vertebral/cirugía , Columna Vertebral/patología , Pronóstico , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/cirugía , Neoplasias Meníngeas/patología
18.
World Neurosurg ; 189: 70-76, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38825313

RESUMEN

BACKGROUND: Surgical management of lumbar spondylolisthesis requires neural decompression, stabilization, and alignment restoration. Minimally invasive spine approaches offer a wide variety of advantages for spondylolisthesis management. This intraoperative note describes the treatment of L4-L5 lumbar spondylolisthesis with lateral lumbar interbody fusion (LLIF) and percutaneous pedicle screw fixation (PSF). METHODS: The surgical technique for treating L4-L5 lumbar spondylolisthesis using a minimally invasive approach with LLIF and percutaneous PSF is described. This operative technique is illustrated with figures, and an intraoperative case example of its application is described. RESULTS: LLIF with percutaneous PSF can be a safe, effective, and reliable option for treating lumbar spondylolisthesis when applied with appropriate surgical technique in a selected patient population. This technique is a valuable addition to the range of available spine surgical options. CONCLUSIONS: LLIF with percutaneous PSF can be an effective technique for treating lumbar L4-L5 spondylolisthesis.

19.
J Neurosurg Spine ; : 1-7, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38905710

RESUMEN

OBJECTIVE: The mini-open lateral retropleural (MO-LRP) approach is an effective option for surgically treating thoracic disc herniations, but the approach raises concerns for pneumothorax (PTX). However, chest tube placement causes insertion site tenderness, necessitates consultation services, increases radiation exposure (requires multiple radiographs), delays the progression of care, and increases narcotic requirements. This study examined the incidence of radiographic and clinically significant PTX and hemothorax (HTX) after the MO-LRP approach, without the placement of a prophylactic chest tube, for thoracic disc herniation. METHODS: This study was a single-institution retrospective evaluation of consecutive cases from 2017 to 2022. Electronic medical records were reviewed, including postoperative chest radiographs, radiology and operative reports, and postoperative notes. The presence of PTX or HTX was determined on chest radiographs obtained in all patients immediately after surgery, with interval radiographs if either was present. The size was categorized as large (≥ 3 cm) or small (< 3 cm) based on guidelines of the American College of Chest Physicians. PTX or HTX was considered clinically significant if it required intervention. RESULTS: Thirty patients underwent thoracic discectomy via the MO-LRP approach. All patients were included. Twenty patients were men (67%), and 10 (33%) were women. The patients ranged in age from 25 to 74 years. The most commonly treated level was T11-12 (n = 11, 37%). Intraoperative violation of parietal pleura occurred in 5 patients (17%). No patient had prophylactic chest tube placement. Fifteen patients (50%) had PTX on postoperative chest radiographs; 2 patients had large PTXs, and 13 had small PTXs. Both patients with large PTXs had expansion on repeat radiographs and were treated with chest tube insertion. Of the 13 patients with a small PTX, 1 required 100% oxygen using a nonrebreather mask; the remainder were asymptomatic. One patient, who had no abnormal findings on the immediate postoperative chest radiograph, developed an incidental HTX on postoperative day 6 and was treated with chest tube insertion. Thus, 3 patients (10%) required a chest tube: 2 for expanding PTX and 1 for delayed HTX. CONCLUSIONS: Most patients who undergo thoracic discectomy via the MO-LRP approach do not develop clinically significant PTX or HTX. PTX and HTX in this patient population should be treated with a chest tube only when there are postoperative clinical and radiographic indications.

20.
World Neurosurg ; 188: e64-e70, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38754550

RESUMEN

OBJECTIVE: Degenerative diseases of the lumbar spine decrease lumbar lordosis (LL). Anterior lumbar interbody fusion (ALIF) at the L5-S1 disc space improves segmental lordosis, LL, and sagittal balance. This study investigated reciprocal changes in spinopelvic alignment after L5-S1 ALIF. METHODS: A retrospective chart review identified patients who underwent L5-S1 ALIF with or without posterior fixation at a single institution (November 1, 2016 to October 1, 2021). Changes in pelvic tilt, sacral slope, proximal LL (L1-L4), distal LL (L4-S1), total LL (L1-S1), segmental lordosis, pelvic incidence-LL mismatch, thoracic kyphosis, cervical lordosis, and sagittal vertical axis were measured on preoperative and postoperative radiographs. RESULTS: Forty-eight patients were identified. Immediate postoperative radiographs were obtained at a mean (SD) of 17 (20) days after surgery; delayed radiographs were obtained 184 (82) days after surgery. After surgery, patients had significantly decreased pelvic tilt (15.71° [7.25°] vs. 17.52° [7.67°], P = 0.003) and proximal LL (11.86° [10.67°] vs. 16.03° [10.45°], P < 0.001) and increased sacral slope (39.49° [9.27°] vs. 36.31° [10.39°], P < 0.001), LL (55.35° [13.15°] vs. 51.63° [13.38°], P = 0.001), and distal LL (43.17° [9.33°] vs. 35.80° [8.02°], P < 0.001). Segmental lordosis increased significantly at L5-S1 and decreased significantly at L2-3, L3-4, and L4-5. Lordosis distribution index increased from 72.55 (19.53) to 81.38 (22.83) (P < 0.001). CONCLUSIONS: L5-S1 ALIF was associated with increased L5-S1 segmental lordosis accompanied by pelvic anteversion and a reciprocal decrease in proximal LL. These changes may represent a reversal of compensatory mechanisms, suggesting an overall relaxation of spinopelvic alignment after L5-S1 ALIF.


Asunto(s)
Lordosis , Vértebras Lumbares , Sacro , Fusión Vertebral , Humanos , Fusión Vertebral/métodos , Femenino , Vértebras Lumbares/cirugía , Vértebras Lumbares/diagnóstico por imagen , Masculino , Estudios Retrospectivos , Persona de Mediana Edad , Lordosis/diagnóstico por imagen , Lordosis/cirugía , Anciano , Sacro/diagnóstico por imagen , Sacro/cirugía
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