A Novel Marking Technique for Accurate Minimal Invasive Approaches in Spine Tumor Surgeries With Activated Carbon Marking.

BACKGROUND AND OBJECTIVES: To describe a novel, practical, reproducible, and effective preoperative marking technique for accurate localization of the spinal level in a series of patients with tumor lesions. METHODS: We retrospectively analyzed patients undergoing minimally invasive (MIS) surgery for spine tumors from 2016 to 2021, in which this marking technique was used. Twenty-one patients, with tumor lesions involving difficult radioscopic visualization (cervicothoracic junction or upper dorsal spine, C6-T8), were included. Tumor lesion level was previously determined with enhanced MRI in all cases. Twenty-four to forty-eight hours before surgery, computed tomography image-guided carbon marking was performed by administration of aqueous suspension of carbon with a 21-gauge needle placed resembling the MIS approach planned trajectory. During surgery, activated carbon marking was followed until reaching the final target on the bone. Next, sequential dilators and an MIS retractor were placed. Then, bone resection and tumor exeresis were performed according to the case. RESULTS: Average age was 60.6 years (26-76 years). Fifteen (71%) patients were women. In most cases (76%), tumor pathology involved intradural lesions (meningiomas and schwannomas). In all cases, the marking described allowed to accurately guide the MIS approach to tumor site. Neither intraoperative fluoroscopy nor approach enlargement was required in any procedure. Postoperative complications were reported in only 4 patients, none related with the marking. CONCLUSION: Computed tomography image-guided activated carbon marking allows to accurately lead MIS approaches in a practical, reproducible, and effective way in cases of tumors localized in regions of the spine of difficult radioscopic visualization.

Artificial Intelligence Assistance for the Measurement of Full Alignment Parameters in Whole-Spine Lateral Radiographs.

BACKGROUND: Measuring spinal alignment with radiological parameters is essential in patients with spinal conditions likely to be treated surgically. These evaluations are not usually included in the radiological report. As a result, spinal surgeons commonly perform the measurement, which is time-consuming and subject to errors. We aim to develop a fully automated artificial intelligence (AI) tool to assist in measuring alignment parameters in whole-spine lateral radiograph (WSL X-rays). METHODS: We developed a tool called Vertebrai that automatically calculates the global spinal parameters (GSPs): Pelvic incidence, sacral slope, pelvic tilt, L1-L4 angle, L4-S1 lumbo-pelvic angle, T1 pelvic angle, sagittal vertical axis, cervical lordosis, C1-C2 lordosis, lumbar lordosis, mid-thoracic kyphosis, proximal thoracic kyphosis, global thoracic kyphosis, T1 slope, C2-C7 plummet, spino-sacral angle, C7 tilt, global tilt, spinopelvic tilt, and hip odontoid axis. We assessed human-AI interaction instead of AI performance alone. We compared the time to measure GSP and inter-rater agreement with and without AI assistance. Two institutional datasets were created with 2267 multilabel images for classification and 784 WSL X-rays with reference standard landmark labeled by spinal surgeons. RESULTS: Vertebrai significantly reduced the measurement time comparing spine surgeons with AI assistance and the AI algorithm alone, without human intervention (3 minutes vs. 0.26 minutes; P < 0.05). Vertebrai achieved an average accuracy of 83% in detecting abnormal alignment values, with the sacral slope parameter exhibiting the lowest accuracy at 61.5% and spinopelvic tilt demonstrating the highest accuracy at 100%. Intraclass correlation analysis revealed a high level of correlation and consistency in the global alignment parameters. CONCLUSIONS: Vertebrai's measurements can accurately detect alignment parameters, making it a promising tool for measuring GSP automatically.

Navigating the Indeterminate Zone: Surgeons' Decision-Making Factors in Treating Vertebral Metastases with Spinal Instability Scores of 7-12.

BACKGROUND: The Spinal Instability Neoplastic Score (SINS) classification system is a validated and the most widely accepted instrument for defining instability in vertebral metastasis (VM), in which lesions scoring between 7 and 12 are defined as indeterminate and the treatment is controversial. This study aimed to determine which variables more frequently are considered by spine surgeons for choosing between the conservative and the surgical treatment of VMs among patients with an indeterminate SINS. METHODS: A single-round online survey was conducted with 10 spine surgeons with expertise in the management of VMs from our AO Spine Region. In this survey, each surgeon independently reviewed demographic and cancer-related variables of 36 real-life cases of patients with vertebral metastases scored between 7 and 12 in the SINS. Bivariate and multivariate analyses were performed to identify significant SINS and non-SINS variables influencing the decision-making on surgical treatment. RESULTS: The most commonly variables considered important were the SINS element "mechanical pain", rated important for 44.4% of the cases, "lesion type" for 36.1%, and "degree of vertebral collapse" and the non-SINS factor "tumor histology" rated for 13.9% of cases. By far the factor most commonly rated unimportant was "posterior element compromise" (in 72.2% of cases). CONCLUSIONS: Surgeons relied on mechanical pain and type of metastatic lesion for treatment choices. Vertebral collapse, spinal malalignment, and mobility were less influential. Spinal mobility was a predictor of surgical versus non-surgical treatment. The only variables not identified either by surgeons themselves or as a predictor of surgery selection was the presence/degree of posterolateral/posterior element involvement.

Minimally Invasive Approaches for Lumbosacral Plexus Schwannomas.

BACKGROUND AND OBJECTIVES: Lumbosacral plexus schwannomas (LSPSs) are benign, slow-growing tumors that arise from the myelin sheath of the lumbar or sacral plexus nerves. Surgery is the treatment of choice for symptomatic LSPSs. Conventional retroperitoneal or transabdominal approaches provide wide exposure of the lesion but are often associated with complications in the abdominal wall, lumbar or sacral plexus, ureter, and intraperitoneal organs. Advances in technology and minimally invasive (MIS) techniques have provided alternative approaches with reliable efficacy compared with traditional open surgery. We describe 3 MIS approaches using tubular retractor systems according to the lesion level. METHODS: This was a multicenter, retrospective observational cohort study to evaluate the use of MIS tubular approaches for surgical resection of LSPSs. We included 23 lumbar and upper sacral plexus schwannomas. Clinical presentation, spinal level, surgical duration, degree of resection, days of hospitalization, pathological anatomy of the tumor, approach-related surgical difficulties, and outcomes were collected. RESULTS: The posterior oblique approach was used in 43.5% of the cases, the transpsoas approach in 39.1%, and the transiliac in 17.4%. The mean operative time was 3.3 hours, and the mean hospitalization was 2.5 days. All tumors were WHO grade 1 schwannoma. Postoperative MRI confirms gross total resection in 91.3% of the patients. No patient requires instrumentation. The pros and cons of each approach were summarized. CONCLUSION: The MIS approaches adapted to the lumbar level may improve surgeons' comfort allowing a safe resection of retroperitoneal LSPS.

Measuring the Delay in the Referral of Unstable Vertebral Metastasis to the Spine Surgeon: A Retrospective Study in a Latin American Institution.

Background: The delay in the referral of patients with potential surgical vertebral metastasis (VM) to the spine surgeon is strongly associated with a worse outcome. The spinal instability neoplastic score (SINS) allows for determining the risk of instability of a spine segment with VM; however, it is almost exclusively used by specialists or residents in neurosurgery or orthopedics. The objective of this work is to report the delay in surgical consultation of patients with potentially unstable and unstable VM (SINS >6) at our center. Material: We performed a 5-year single-center retrospective analysis of patients with spine metastasis on computed tomography (CT). Patients were divided into Group 1 (G1), potentially unstable VM (SINS 7-12), and Group 2 (G2), unstable VM (SINS 13-18). Time to surgical referral was calculated as the number of days between the report of the VM in the CT and the first clinical assessment of a spinal surgeon on the medical records. Results: We analyzed 220 CT scans, and 98 met the selection criteria. Group 1 had 85 patients (86.7%) and Group 2 had 13 (13.3%). We observed a mean time to referral of 83.5 days in the entire cohort (std = 127.6); 87.6 days (std = 135.1) for G1, and 57.2 days (std = 53.8) for G2. The delay in referral showed no significant correlation with the SINS score. Conclusion: We report a mean delay of 83.5 days in the surgical referral of VM (SINS >6, n = 98). Both groups showed cases of serious referral delay, with 25% of patients having the first surgical consultation more than three months after the CT study.

Carbon-Assisted Minimally Invasive Transtubular Approach for Intercostal Nerve Schwannoma.

BACKGROUND AND OBJECTIVES: The intraoperative localization of an intercostal nerve schwannoma (INS) is extremely difficult because the lesion is generally not palpable, and the fluoroscopic visualization of anatomic landmarks in the ribs is unsatisfactory. Using activated carbon suspension to mark the soft-tissue approach could improve INS localization. We present a novel, simple, reproducible carbon-assisted minimally invasive transtubular approach for an INS. METHODS: The patient was a 57-year-old man with a painful 12th left INS arising below the floating rib. A computed tomography image-guided, tumor-to-skin marking with aqueous carbon suspension was performed 48 hours before surgery. A minimally invasive transtubular approach following the carbon path allowed a precise tumor location. RESULTS: The INS was completely removed. The patient's thoracic radicular pain was immediately relieved after surgery. He was discharged the following day with residual numbness on the left thoracic side. At the 5-year follow-up, no tumor recurrence was noted in the control MRI. CONCLUSION: This article presents an alternative novel technique for resecting an intercostal schwannoma. Using a transtubular approach with carbon-marking assistance allowed a tumor gross total resection with immediate pain relief and a successful outcome.

Navigated multiplanar osteotomies for spinal primary bone tumors.

BACKGROUND: Establishing the proper diagnosis and rendering appropriate treatment of spinal primary bone tumors (SPBT) can result in definitive cures. Notably, malignant, or benign SPBT (i.e., with aggressive local behavior) generally require en bloc resection. Osteotomies of the vertebral body in more than 1 plane may avoid critical structures, preserve nerve functions, and reduce the volume of healthy bone resected. Here, our objective was to report how we planned and performed navigated multiplanar osteotomies for en bloc resection of 14 SPBT. METHODS: We performed a retrospective analysis of 14 patients with malignant or locally aggressive benign SPBT operated on consecutively between 2014 and 2019 utilizing preoperative 3D planning/navigation. Tumors were resected in an en bloc fashion utilizing multiplanar osteotomies. Patients were followed for a minimum of 12 postoperative months. RESULTS: Diagnoses included three benign but locally aggressive bone tumors (i.e., all osteoblastomas) and 11 primary sarcomas (i.e., six chordomas and five chondrosarcomas). Eleven tumors involved the sacrum and the other three, the thoracic spine. In 12 patients, the en bloc margins were classified as marginal (<1 cm), and in two patients, as wide (>1 cm). Intraoperative navigation facilitated the performance of 40 osteotomies in 14 patients (median = 2.9, range = 2-6). CONCLUSION: Navigated multiplanar osteotomies increased the precision and safety of en bloc resections for 14 primary spinal bone tumors SPBT that included 11 malignant and three benign/locally aggressive lesions.

20 Tips to Avoid and Handle Problems in the Placement of Percutaneous Pedicle Screws.

BACKGROUND: Two-dimensional fluoroscopy-guided percutaneous pedicle screw placement is currently the most widely applied instrumentation for minimally invasive treatment of spinal injuries requiring stabilization. Although this technique has advantages over open instrumentation, it also presents new challenges and specific complications. The objective of this study was to provide recommendations developed from the experience of several spinal surgeons at different minimally invasive spine surgery reference centers to solve specific problems and prevent complications during the learning curve of this technique. METHODS: An AO Spine Latin America minimally invasive spine surgery study group analyzed the most frequent complications and challenges occurring during the placement of >14,000 two-dimensional fluoroscopy-guided percutaneous pedicle screws at different centers over 15 years. Twenty tips considered most relevant to performing this technique, excluding problems directly related to specific brands of instruments, were presented. RESULTS: The 20 tips included the following: (1) positioning; (2) clean and painless; (3) fewer x-rays; (4) check the clock; (5) beveled tip; (6) transverse-rib-pedicle; (7) double Jamshidi; (8) hammer the Kirschner wire; (9) bent tip; (10) too loose, too tight; (11) new trajectory; (12) manual control; (13) start over; (14) Kirschner wire first; (15) adhesive drape control; (16) bend the rod; (17) lower rods; (18) freehand inner; (19) posterior fusion; (20) revision. CONCLUSIONS: Implementation of these tips might improve performance of this technique and reduce the complications related to percutaneous pedicle screw placement.

Low Implant Failure Rate of Percutaneous Fixation for Spinal Metastases: A Multicenter Retrospective Study.

OBJECTIVE: To evaluate incidence and types of implant failure observed in a series of patients with spinal metastases (SM) treated with minimally invasive stabilization surgery without fusion. METHODS: In this multicenter, retrospective, observational study, we reviewed the files of patients >18 years old who underwent surgery for SM using percutaneous spinal stabilization without fusion with a minimum 3-month follow-up. The following variables were included: demographics, clinical findings, prior radiation history, SM location, epidural spinal cord compression scale, Spinal Instability Neoplastic Scale, neurological examination, and surgery-related data. Primary outcome measure was implant failure rate, as observed in patients' last computed tomography scan. Multivariable analysis was performed to identify baseline factors and factors associated with implant failure. RESULTS: Analysis included 72 patients. Mean age of patients was 62 years, 39 patients were men, and 75% of patients had an intermediate Spinal Instability Neoplastic Scale score. Tumor separation surgery was performed in 48.6% of patients. Short instrumentation was indicated in 54.2% of patients. Three patients (4.2%) experienced implant failure (2 screw loosening, 1 screw cut-out); none of them required revision surgery. In 73.6% of cases, survival was >6 months. No significant predictors of failure were identified in the multivariate analysis. CONCLUSIONS: A low implant failure rate was observed over the short and medium term, even when short instrumentations without fusion were performed. These findings suggest that minimally invasive stabilization surgery without fusion may be an effective and safe way to treat complicated SM.

COVID-19 Impact Among Spine Surgeons in Latin America.

STUDY DESIGN: Cross-sectional study. OBJECTIVE: The aim of this study was to evaluate the impact of the COVID-19 outbreak in spine surgeons in Latin America. METHODS: A questionnaire was sent to Latin American spine surgeons from April 4 to 6, 2020. Surgeon characteristics were recorded. The impact of COVID-19 on economic well-being, work, and mental health were also determined. All variables were compared and analyzed. RESULTS: Two hundred four surgeons answered the complete survey; most of them were male (96.6%), the average age was 47.7 years; 58.8% (n = 120) were orthopedic surgeons and 41.2% (n = 84) were neurosurgeons. The majority of the respondents were from Argentina (59.8%, n = 122), followed by Brazil (17.2%, n = 35), Chile (6.4%, n = 13), and Mexico (5.9%, n = 12). Most of the surgeons reported performing emergency procedures only during the pandemic (76.5%, n = 156). Half used telemedicine or online consultation modalities (54.4%, n = 111). The average concern about the financial situation due to the pandemic was 7.53 in a scale of 1 to 10 (10 being the worst scenario). Twenty-two percent (n = 45) of the surgeons had a score over 10 in the Patient Health Questionnaire (PHQ-9; scores higher than 10 needs referral to confirm depression diagnosis). Young age and neurosurgery as a specialty were associated with higher PHQ-9 scores. CONCLUSIONS: COVID-19 has an impact in the daily working practice and financial situation of spine surgeons in Latin America. The long-term psychological impact should be taken into consideration to avoid a heavier burden for health care providers.

Impacto psicosocial de la pandemia por COVID-19 en cirujanos de columna argentinos / Psychosocial impact of the COVID-19 pandemic on Argentine spinal surgeons

Objetivo: Evaluar el impacto psicosocial de la pandemia por COVID-19 en los cirujanos de columna de Argentina. Material y métodos: Se envió un cuestionario diseñado específicamente a los cirujanos de columna de Argentina entre el 4-6 de abril del 2020. Las preguntas incluyeron variables demográficas, económicas, laborales y la escala de depresión PHQ-9. Las variables fueron comparadas y analizadas y las diferencias estadísticamente significativas remarcadas. Resultados: Respondieron en forma completa la encuesta 122 cirujanos de columna de Argentina, la mayoría hombres (97%), la edad promedio fue de 44 años; la mitad (n: 61) eran traumatólogos y la otra mitad neurocirujanos. La mayoría respondieron estar solo haciendo cirugías de emergencia (84%, n: 102). La preocupación promedio respecto a la situación financiera fue de 7.8 en una escala de 1 al 10. El 20% (n: 24) tenía un score superior a 10 en la escala de PHQ-9. Los cirujanos más jóvenes y los neurocirujanos tenían estadísticamente scores de PHQ-9 más altos. Conclusión: Se evaluó el impacto durante la pandemia por COVID-19 en la situación laboral y financiera de los cirujanos de columna encuestados. El impacto psicológico en el largo plazo debe ser considerado, para evitar secuelas en este grupo de profesionales de la salud.

Objective: The aim of this study is to evaluate the psycho-social impact of the COVID-19 outbreak in spine surgeons in Argentina. Methods: A questionnaire was sent to Argentina spine surgeons from April 4-6th, 2020. Questions regarding demographics, economic, working status and the PHQ-9 score were included. All variables were compared, analyzed and statistically significant differences were recorded. Results: 122 surgeons from Argentina answered the complete survey, most of them were male (97 %), the average age was 44 years; half (n: 61) of them were orthopedic surgeons and half neurosurgeons. Most of the surgeons reported performing emergency procedures only during the pandemic (84 %, n: 102). The average concern about the financial situation due to the pandemic was 7.8 in a scale of 1 to 10. Twenty percent (n: 24) of the surgeons had a score over 10 in the PHQ-9. Young age and neurosurgery as a specialty were statistically related with higher PHQ-9 scores. Conclusions: COVID-19 impact ́s in working practice and financial situation of Argentina ́s spine surgeons that answered this survey was evaluated. The long-term psychological impact should be taken into consideration to avoid a heavier burden for health care providers.

Neurocirugía en época de COVID-19. Protocolo de actuación / Neurosurgery in the time of COVID-19. Action protocol

El manejo de pacientes debido a la aparición del nuevo coronavirus 2019 (COVID-19) representa un desafío para los equipos médicos y quirúrgicos, ya que modificó el funcionamiento de los sistemas de salud en casi todo el mundo. Para contribuir a la re organización del sistema de salud, el Servicio de Neurocirugía del Hospital Italiano de Buenos Aires trabajó en adoptar distintas medidas en concordancia con las tomadas a nivel institucional y nacional; por lo que se analizó la bibliografia publicada, asi como las normas dictadas por el comité de crisis de nuestra institucion. A su vez realizamos una breve encuesta dirigida a neurocirujanos de america latina para conocer como se manejaban actualmente en relación a niveles de protección y realización de cirugias. La actual pandemia de COVID-19 es el mayor desafío que enfrentan los sistemas nacionales de salud en los últimos tiempos. Los neurocirujanos podemos contribuir a la reducción del riesgo de infección nosocomial de los trabajadores de la salud al adaptar distintos protocolos en pacientes con COVID-19.

Patient's management due to the appearance of new coronavirus 2019 (COVID-19) represents a challenge for medical and surgical departments, since it modified the running of health systems in almost all the world. In order to help in this new situation, the Neurosurgical Department of our institution has adopted different measures in accordance with those taken at institutional and national level. In order to do this, we made a literature review and we added to this, the norms dictated by the crisis committee of our hospital. We also carried out a brief survey among neurosurgeons from Latin America to find out how they managed protection levels in relation to surgery. COVID-19 pandemic is certainly one of the greatest challenge national health systems face in a century. Adapting different protocols in neurosurgical patients with COVID-19 can contribute in reducing the risk of nosocomial infection of health workers.

Cirugía mínimamente invasiva en el tratamiento de fracturas tóracolumbares / Minimally invasive surgery in the treatment of thoracolumbar fractures

Objetivo: Analizar y describir una serie de fracturas tóraco-lumbares traumáticas tratadas con cirugía mínimamente invasiva. Material y métodos: Analizamos una serie de 26 pacientes con fracturas traumáticas tóraco-lumbosacras entre 2010-2017. Las imágenes pre-operatorias fueron clasificadas usando la clasificación AO. Analizamos en forma pre y post operatoria: escala visual analógica, volumen de pérdida sanguínea, duración de la hospitalización, complicaciones, cirugías asociadas en otros órganos, extracción de implantes en el largo plazo, estado neurológico pre y post quirúrgico y mortalidad.Los pacientes con historias clínicas completas, TAC pre-operatoria y un seguimiento mínimo de 12 meses fueron incluidos (18 hombres y 8 mujeres). La edad promedio fue de 28.7 años (21-84 años); seguimiento promedio de 28 meses (13-86 meses). Dieciocho pacientes fueron manejados con instrumentaciones percutáneas, 8 recibieron vertebroplastias, y en 5 casos se realizó además algún gesto de artrodesis. Resultados: La EVA mejoró 7 puntos promedio respecto al pre-operatorio; el promedio de sangrado fue de 40 mL, no observamos ningún caso de empeoramiento neurológico. La duración promedio de la hospitalización fue de 3.9 días. Cuatro enfermos necesitaron alguna cirugía en otro órgano producto de sus politraumatismos.Los tornillos percutáneos fueron removidos en 9 casos luego de la consolidación. Como complicaciones tuvimos: 1 hematoma retroperitoneal autolimitado, una fractura pedicular y una cánula de cementación rota adentro de un pedículo. Conclusión: La cirugía mínimamente invasiva en trauma espinal es una alternativa válida que permite estabilización, movilización precoz y logra buenos resultados en términos de control del dolor con baja tasa de complicaciones

Objective: To analyze and describe a series of trauma-related thoraco-lumbo-sacral vertebral fractures managed with minimally invasive surgery. Methods: We retrospectively review the charts and images of 26 patients with thoracolumbar spine fractures between 2010-2017. Pre-op images were assessed and fractures were classified according to the thoraco-lumbar trauma AO Spine classification. We analyzed pre and post-surgical visual analog scale (VAS), blood loss during surgery, hospital length of stay, complications, associated surgical procedures, long term post-op implant removal, pre and post neurological status and mortality.Patients with a complete case record, pre-op CT scans and minimum 12-month follow up were included (18 males and 8 females). Mean age was 28.7 years (21-84 years); mean post-op follow up was 28 month (13-86 months). Eighteen patients were managed with percutaneous instrumentation, 8 patients also received percutaneous vertebroplasty, and 5 patients underwent also some arthrodesis procedure. Results: VAS improved 7 points as compared to the pre-op score; mean blood loss was 40 mL, we did not observed any neurological deficit worsening. Mean hospital length of stay was 3.9 days. Four patients needed surgical procedures involving other organs due to politrauma. Percutaneous screws were removed in 9 cases after fracture consolidation. Complications were: one case of self-limiting retroperitoneal hematoma, one case of pedicle screw fracture and one cement broken cannula into the pedicle. Conclusion: Minimally invasive surgery in spine trauma is a valid option allowing stabilization, early mobilization, and leading to good outcomes in terms of pain control and a lower complication rate

RODEXKE. Infiltración con ropivacaína, dexmedetomidina y ketorolac en cirugía espinal: Una estrategia para disminuir el consumo de opioides / RODEXKE. Infiltration with ropivacaine, dexmedetomidine, and ketorolac in spinal surgery: A strategy to decrease opioid consumption

Objetivos: Evaluar la efectividad de la infiltración del sitio quirúrgico, con ropivacaína, dexmedetomidina y ketorolac, en pacientes sometidos a instrumentación transpedicular dorsolumbar con técnica mini invasiva, en cuanto al consumo de opioides durante la internación. Materiales y métodos: Se recolectaron en forma retrospectiva los datos prospectivos de las historias clínicas de pacientes con una instrumentación con tornillos transpediculares percutáneos operados entre Junio del 2016 y Diciembre del 2018. 32 pacientes cumplieron con los criterios de selección. Se infiltró en el momento del cierre quirúrgico con una solución preparada con 150 mg de ropivacaína, 0,7 mcg/kg de dexmedetomidina y 60 mg de ketorolac, disuelto en solución fisiológica estéril para completar 40ml (Grupo M) y se la comparó con pacientes en los cuales solo se infiltró con 150mg de ropivacaína (Grupo E). Resultados: El consumo de equivalentes de morfina durante las primeras 72hs postoperatorias presentó en el grupo M una mediana de 0mg, y el grupo E, una mediana de 9,5mg (RIQ de 13,35), con una p<0,000. Por el contrario el consumo de morfina en la sala de recuperación presentó una mediana de 0mg (RIQ de 2) para el grupo M, y de 2mg (RIQ de 5) para el grupo E, sin encontrarse una diferencia significativa, p=0,132. Conclusión: Los resultados obtenidos en la comparación del consumo de opioides durante las primeras 72hs de la internación permite inferir que esta combinación de fármacos es superior respecto a la infiltración estándar con ropivacaína, independientemente de la estrategia analgésica utilizada durante el tiempo quirúrgico.

Objectives: To assess the effectiveness of a surgical site infiltration with ropivacaine, dexmedetomidine and ketorolac, in reducing opioid consumption in patients with a transpedicular dorsolumbar instrumentation using a minimally invasive technique. Materials y methods: We retrospectively collected data from patient's charts from June of 2016 to December of 2018. 32 patients with minimally invasive transpedicular dorsolumbar instrumentation, who met all criteria, were included in the analysis. During wound closure a mixture of 150mg of ropivacaine, 0,7mcg/kg of dexmedetomidine and 60mg of ketorolac, diluted in normal saline to achieve 40ml was injected (Group M). We compared them with patients in whom only 150mg of ropivacaine and saline where injected in the surgical site (Group E). Results: Morphine equivalents use during the first 72 hours postoperative had a median of 0mg for group M, and of 9,5mg (IQR of 13.35), with a p<0,000. On the contrary, morphine use during post anesthesia care unit stance had a median of 0mg (IQR of 2) for group M and of 2mg (IQR of 5) for group E, without a statistically significant difference, p=0,132. Conclusion: The result of the analysis of opioid consumption during the first 72 hours postoperative allows concluding that the infiltration of these 3 drugs together its superior to the standard infiltration with ropivacaine, independently of the analgesic strategy used during the surgery.

Abordaje mínimamente invasivo para el tratamiento de tumores espinales intradurales extramedulares / Minimally invasive approach for the treatment of extramedullary intradural spinal tumors

Introducción: Describir la técnica de abordaje mínimamente invasiva para el tratamiento de tumores intradurales extramedulares en los diferentes segmentos espinales. Material y Métodos: Se detallan la planificación, posicionamiento, marcación, pasos técnicos del abordaje mínimamente invasivo, exéresis lesional y cierre de lesiones ID-EM a nivel cervical, dorsal, lumbar y sacro. Se proporcionan recomendaciones para descomplejizar maniobras quirúrgicas, acortar el tiempo operativo y evitar potenciales complicaciones. Conclusiones: El abordaje MISS es una opción segura y eficaz para el tratamiento quirúrgico de determinados tumores ID-EM.

Objective: To describe the technique of minimally invasive approach for the treatment of intradural extramedullary tumors in the different spinal segments. Material and Methods: The planning, positioning, skin marking, technical steps of the minimally invasive approach, lesion resection, and closure of ID-EM lesions at the cervical, dorsal, lumbar and sacral levels are detailed. Recommendations are provided to simplify surgical maneuvers, shorten operative time and avoid potential complications. Conclusions: The MIS approach is a safe and effective option for the surgical treatment of certain ID-EM tumors.

[Usefulness of minimally invasive spine surgery for the management of thoracolumbar spinal metastases]. / Utilidad de la cirugía espinal mínimamente invasiva en el manejo de las metástasis espinales toraco-lumbares.

OBJECTIVE: To describe the surgical results and evolution of patients who underwent minimally invasive spine surgery (MISS) for the treatment of thoracolumbar spinal metastases, using the NOMS (Neurological, Oncological, Mechanical, Systemic) assessment for the therapeutic decision. METHODS: Patients who underwent MISS technique for the treatment of thoracolumbar spinal metastases were prospectively enrolled at the Hospital Italiano de Buenos Aires, from June 2014 to June 2017. In all cases, the NOMS assessments were performed for therapeutic decision making. Surgical results were analyzed in terms of improvements in Karnofsky performance status, pain relief (VAS - visual analog scale), Frankel, blood loss, need for transfusions, complications, use of opioids and hospitalization length. A P < 0.05 value was considered statistically significant. RESULTS: During the study period 26 patients were included, 13 of them were women. The average age was 57-year-old (27-83 years). Breast cancer was the most frequent primary tumor (27%). The main symptom was pain (96%), although 12 patients presented with myelopathy (46%). High-grade epidural spinal cord compression requiring decompression was observed in 17 cases (65%). According to the SINS (spinal instability neoplastic score), most lesions were potentially unstable or unstable (89%) requiring MISS stabilization. After surgery, pain relief (VAS) and neurological recovery (Frankel) improved significantly in the 77% and 67% of the cases, respectively, with low intraoperative blood loss and without any transfusions. Only one minor surgical complication was presented (4%). The average of hospital stay was 5.5 days. CONCLUSION: In our series and using the NOMS as a therapeutic algorithm, MISS was effective for decompression and spinal stabilization, with a low rate of complications and rapid postoperative recovery.

[Minimally invasive resection of spinal synovial cysts: Technical note]. / Resección mínimamente invasiva de quistes sinoviales espinales. Nota técnica.

OBJECTIVE: To present the treatment algorithm, surgical technique, and results of a series of patients with spinal synovial cysts operated with minimally invasive techniques (MIS). INTRODUCTION: Spinal synovial cysts originate from the dilation and potential rupture of the synovial sheath of a facet joint. Surgical resection is considered the treatment of choice in symptomatic patients. The use of MIS techniques could reduce the disruption of the facet joint involved, reducing the risk of postoperative instability. MATERIALS AND METHODS: We retrospectively evaluated 21 patients with spinal synovial cysts operated by MIS approach and decompression. We analyzed the signs, symptoms, surgical time, hospital stay, evolution, and complications. The visual analog scale (VAS) was used to evaluate pain and the Weiner scale and the modified Macnab criteria to measure the patient's postoperative satisfaction. RESULTS: A total of 21 patients were surgically treated with MIS technique; 76.2% (n = 16) did not require arthrodesis, the remaining 23.8% (n = 5) were fused. We performed 13 (61.9%) contralateral hemilaminectomies, 7 ipsilateral hemilaminectomies (33.3%), and 1 laminectomy in S1-S2. The average follow-up was 26 months; surgical time was 150.33 ± 63.31 min, with a hospital stay of 2.5 ± 1.78 days. The VAS decreased from 8.3 preoperatively to 2.3 postoperatively. Sixteen patients reported excellent results, four good and one regular in the scale of Macnab. 95.2% of patients perceived that the procedure was very/quite successful according to the Weiner scale. CONCLUSION: The minimally invasive approach is a safe and effective procedure for the complete resection of spinal synovial cysts. It provides excellent clinical-functional results by preserving muscles, ligaments, and joint facets.

Flow Diverter for the Treatment of Pseudoaneurysms of the Extracraneal Vertebral Artery: Report of Two Cases and Review of the Literature.

BACKGROUND: Pseudoaneurysms (PAs) of the extracranial vertebral artery (VA) are rare lesions, representing less than 1% of all aneurysms. Although these lesions may resolve spontaneously, they present a high rupture rate, so early preventive treatment is advised. CASE DESCRIPTION: Case 1: A 48-year-old woman presented with pain and cervical rigidity. An angiotomography showed a PA of the left VA at the level of the C2 transverse foramen, with mural thrombosis and bone remodeling of the left lateral mass. The PA was treated with the endovascular placement of a flow diverter stent. The patient was discharged 3 days after the procedure without complications. The last vascular imaging follow-up was performed 6 years after the procedure showing a patent left VA, with complete resolution of the aneurysm. Case 2: A 57-year-old woman was admitted referring cervicalgia after a polytraumatism. An angiotomography revealed a fracture of the C1 posterior arch, lateral mass, and left transverse foramen, on top of a left VA thrombosis due to a vascular dissection. Eleven months after the trauma, a left VA V3 segment arteriovenous fistula developed. It was treated with hydrocoils, with no complications. One month after the embolization, a left VA V3 segment PA was observed and treated with a flow diverter stent. An angiographic follow-up 2 years after the procedure showed a patent left VA, with complete resolution of the PA. CONCLUSION: The use of flow diverters seems to be a safe and effective therapeutic option for the treatment of PAs of the extracranial VAs.

Accuracy in Percutaneous Transpedicular Screws Placement Using Biplane Radioscopy: Systematic Review and Meta-Analysis.

STUDY DESIGN: Systematic review and descriptive data meta-analysis. OBJECTIVE: The objective of this study was to appropriately establish the accuracy in the percutaneous transpedicular screws (PTS) placement using biplane radioscopy (Rx-2D). SUMMARY OF BACKGROUND DATA: The Rx-2D is a widely-used technique for PTS as it is practical, ubiquitous, and cost-effective. However, the reported "acceptable" accuracy attained by this method is widely variable ranging between 76% and 100%. METHODS: A systematic review was conducted to screen publications about PTS placement using Rx-2D guidance. PubMed/MEDLINE database was consulted using the search term "percutaneous pedicle screw" from 1977 to 2017. Previous meta-analysis and reference lists of the selected articles were reviewed. Accuracy values were assessed fulfilling the proposed criteria. Observational data meta-analysis was performed. Cochran's Q test was used to determine heterogeneity among data extracted from the series, which was quantified by I test. P-values≤0.05 were considered statistically significant. The results were depicted by Forest plots. Funnel plots were outlined to visualize a possible bias of publication among the selected articles. RESULTS: In total, 27 articles were included in the analysis. Results of the accuracy were as follow, 91.5% (n=7993; 95% CI, 89.3%-93.6%) of the screws were placed purely intrapedicular, and 96.1% (n=8579; 95% CI, 94.0%-98.2%) when deviation from the pedicle was up to 2 mm. CONCLUSIONS: This meta-analysis is the largest review of PTS placed with Rx-2D guidance reported up to date. We concluded that the procedure is a safe and reproducible technique. The key values obtained in this work set reliable references for both clinical and training outcome assessing.