Radiological diagnostic accuracy study comparing Lenke, Bridwell, BSF, and CT-HU fusion grading scales for minimally invasive lumbar interbody fusion spine surgery and its correlation to clinical outcome.

Prospective randomized double-blinded diagnostic accuracy study about radiological grading of fusion after minimally invasive lumbar interbody fusion procedures (MI-LIFP).To determinate the intra and the inter-observer correlation between different radiological lumbar interbody fusion grading scales (RLIFGS) in patients undergoing MI-LIFP and their correlation to clinical outcome.Besides technological improvements in medical diagnosis and the many existing RLIFGS, surgical exploration continues to be the gold-standard to assess fusion in patients with radiological pseudarthrosis, with little if any research on the relationship between RLIFGS and clinical outcome.We collected data from patients undergoing MI-LIFP procedures operated by a single surgeon from 2009 to 2017, which had follow-up and CT-scan control greater than 12 months, whose clinical registers specified lumbar and radicular visual analogue scale (L and R-VAS) and Oswestry Disability Index (ODI) score preoperatively and at the end of follow-up. Interbody fusion levels were coded for blinded evaluation by three different minimally invasive spine (MIS) surgeons, using Lenke, Bridwell, BSF (Brantigan, Steffe, Fraser), and CT-HU RLIFGS. We established fusion criteria, as described in their original papers. Another independent spine surgeon blindly evaluated successful clinical outcome (SCO), defined as a significant improvement in 2 of 3 of the following issues: L-VAS, R-VAS, or ODI score at follow-up; otherwise, rated as clinical pseudarthrosis. Radiological and clinical data was coded and statistically analyzed using Student T-Test, Pearson P-Test, and ANOVA with statistical package for the social sciences 21 by another blinded researcher, positive and negative predictive values were also calculated for each RLFGS.We found a significant clinical improvement with a moderate intra-observer correlation between scales and no inter-observer or clinical correlation, with no sub-group statistically significant differences.This paper represents the first study about the diagnostic accuracy of RLFGS, we concluded that their diagnostic accuracy is pretty low to determine fusion or pseudoarthrosis based on its low correlation to clinical outcome, we recommend surgeons rely on clinical findings to decide whether a patient has clinical fusion or pseudoarthrosis based on successful clinical outcome.

Dysphagia rates after minimally invasive tubular approach to the anterior cervical spine.

INTRODUCTION: Cervical spine surgery (anterior cervical spine surgery [ACSS]) is a commonly indicated to provide neurological decompression, correct deformity, and preserve stability. Current series report good to excellent results, but a number of patients suffer from dysphagia with reported rates as high as 80%. MATERIALS AND METHODS: Retrospective cohort of patients undergoing ACSS (anterior cervical discectomy and fusion [ACDF]; and arthroplasty, total disc replacement [TDR]) from 2013 to 2017 by a single surgeon. We collected demographic data, surgical outcomes, clinical outcomes, and dysphagia incidence and magnitude (visual analog scale [VAS]), we analyzed results with SPSS 22. RESULTS: A total of 81 patients operated from 2013 to 2018, ACDF was performed in 70, and TDR was performed in 11, mean surgical time was 156.8, mean neck pain and radicular pain VAS reduced significantly in both groups (p < 0.01). Dysphagia was encountered in 18 ACDF patients, and one TDR patient. Overall dysphagia rate was 9.1% in day-1 post-operative, with mean 0.27 magnitude (standard deviation [SD] 0.4) in ACDF group and 0.18 (0.6 SD) in TDR group, 1-month follow-up dysphagia rate was 0%. CONCLUSIONS: Minimally invasive techniques may reduce post-operative dysphagia related to soft-tissue trauma, to 9% in day-1 post-operative (as compared to 39%), and to 0% (as compared to 8.5% reported worldwide) by 1-month follow-up.

ANTECEDENTES: La cirugía cervical anterior (CCA) esta comúnmente indicada para proporcionar descompresión neurológica, corregir deformidades y preservar la estabilidad. Las series actuales reportan tasas de disfagia de hasta el 80%. MÉTODO: cohorte retrospectiva de pacientes sometidos a CCA (discectomía y fusión cervical anterior [DFCA], y artroplastia total de disco [ATD]) de 2013 a 2017. Se recopilaron datos demográficos, quirúrgicos, clínicos y de incidencia y magnitud de la disfagia (escala visual analógica [EVA]). Se analizaron los resultados con SPSS 22. RESULTADOS: 81 pacientes operados de 2013 a 2018, ACDF en 70 y ATD en 11, tiempo quirúrgico promedio de 156.8 minutos. La puntuación en la EVA cervical y radicular se redujo significativamente en ambos grupos (p < 0.01). Hubo disfagia en 18 pacientes con DFCA y en uno con ATD. La tasa de disfagia fue del 9.1% en el primer día de posoperatorio, con EVA de 0.27 (desviación estándar [DE]: 0.4) en el grupo DFCA y de 0.18 (DE: 0.6) en el grupo ATD. La tasa de disfagia de seguimiento a 1 mes fue del 0%. CONCLUSIONES: Las técnicas mínimamente invasivas reducen la disfagia posoperatoria en CCA al 9% en el primer día (en comparación con el 39%) y al 0% (en comparación con el 8.5% reportado mundialmente) al mes de seguimiento.

Assessment of Paraspinal Muscle Atrophy Percentage after Minimally Invasive Transforaminal Lumbar Interbody Fusion and Unilateral Instrumentation Using a Novel Contralateral Intact Muscle-Controlled Model.

STUDY DESIGN: Retrospective comparative clinical study. PURPOSE: This study aimed to assess paraspinal muscle atrophy in patients who underwent minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) and unilateral pedicle screw fixation using a novel contralateral intact muscle-controlled model. OVERVIEW OF LITERATURE: The increased incidence of paravertebral lumbar muscle injuries after open techniques has raised the importance of implementing minimally invasive spine surgical techniques using tubular retractors and minimally invasive screw placement. The functional cross-sectional area (FCSA) represents the lean muscle mass; furthermore, FCSA is a useful marker of the contractile ability of a muscle following a spine surgery. However, the benefits of unilateral fixation and MI-TLIF on paraspinal muscles have not been defined. METHODS: We performed a retrospective imagenological review on eleven patients who underwent unilateral MI-TLIF and unilateral transpedicular screw lumbar placement. FCSAs of the multifidus and erector spinae were measured 1 year after surgery at adjacent levels and were compared to the contralateral intact muscles. Measurement differences between the surgical and nonsurgical sites were compared. The interobserver reliability was calculated using an intraclass correlation coefficient. RESULTS: The mean FCSA at the surgical site was 20.97±5.07 cm2 at the superior level and 8.89±2.87 cm2 at the inferior level. The mean FCSA at the contralateral nonsurgical site was 20.15±5.95 cm2 at the superior level and 9.20±2.66 cm2 at the inferior level was. The superior and inferior FCSA measurements showed no significant difference between the surgical and nonsurgical sites (p=0.5, p=0.922, respectively). CONCLUSIONS: Using a mini-open tubular approach through the sulcus between the longissimus and iliocostalis, MI-TLIF and unilateral pedicle screw instrumentation produced minimal paraspinal muscle damage at the superior and inferior adjacent levels.

Learning curve in single-level minimally invasive tlif: experience of a neurosurgeon / Curva de aprendizagem em tlif minimamente invasiva em um nível: experiência de um neurocirurgião / Curva de aprendizaje en tlif por mínima invasión de un nivel: experiencia de un neurocirujano

ABSTRACT Objective: To describe the learning curve that shows the progress of a single neurosurgeon when performing single-level MI-TLIF. Methods: We included 99 consecutive patients who underwent single-level MI-TLIF by the same neurosurgeon (JASS). Patient's demographic characteristics were analyzed. In addition, surgical time, intraoperative blood loss and hospital stay were evaluated. The learning curves were calculated with a piecewise regression model. Results: The mean age was 54.6 years. The learning curves showed an inverse relationship between the surgical experience and the variable analyzed, reaching an inflection point for surgical time in case 43 and for blood loss in case 48. The mean surgical time was 203.3 minutes (interquartile range [IQR] 150-240 minutes), intraoperative bleeding was 97.4ml (IQR 40-100ml) and hospital stay of four days (IQR 3-5 days). Conclusions: MI-TLIF is a very frequent surgical procedure due to its effectiveness and safety, which has shown similar results to open procedure. According to this study, the required learning curve is slightly higher than for open procedures, and is reached after about 45 cases.

RESUMO Objetivo: Descrever a curva de aprendizagem que mostra o progresso de um único neurocirurgião na realização de MI-TLIF em um só nível. Métodos: Foram incluídos 99 pacientes consecutivos submetidos a MI-TLIF de um só nível pelo mesmo neurocirurgião (JASS). Foram analisadas as características demográficas dos pacientes. Além disso, avaliou-se o tempo operatório, a perda de sangue intraoperatória e o tempo de internação hospitalar. As curvas de aprendizagem foram realizadas com um modelo de regressão segmentada. Resultados: A média de idade foi 54,6 anos. As curvas de aprendizagem mostraram uma relação inversa entre a experiência cirúrgica e a variável analisada, atingindo um ponto de inflexão para o tempo de cirurgia no caso 43 e da perda sanguínea no caso 48. O tempo médio de cirurgia foi de 203,3 minutos (amplitude interquartil [IQR] 150 - 240 minutos), de sangramento intraoperatório foi 97,4 ml (IQR 40-100 ml) e de internação hospitalar foi de quatro dias (IQR 3-5 dias). Conclusões: O MI-TLIF é um procedimento realizado com muita frequência devido à sua eficácia e segurança, que tem mostrado resultados comparáveis com o procedimento aberto. De acordo com este estudo, a curva de aprendizagem necessária é ligeiramente maior do que para os procedimentos abertos, sendo que é atingida depois de cerca de 45 casos.

RESUMEN Objetivo: Describir la curva de aprendizaje que muestre el progreso de un sólo neurocirujano para la realización de MI-TLIF de un sólo nivel. Métodos: Se incluyeron 99 pacientes consecutivos sometidos a MI-TLIF en un solo nivel por un mismo neurocirujano (JASS). Se analizaron las características demográficas de los pacientes. Además se evaluó el tiempo quirúrgico, sangrado transoperatorio y tiempo de estancia hospitalaria. Las curvas de aprendizaje se realizaron con un modelo de regresión dividida en segmentos. Resultados: Se obtuvo un promedio de edad de 54,6 años. Las curvas de aprendizaje mostraron una relación inversa entre la experiencia quirúrgica y la variable analizada, alcanzando un punto de inflexión para tiempo quirúrgico en el caso 43 y para el sangrado en el caso 48. El promedio de tiempo quirúrgico fue de 203,3 minutos (amplitud intercuartil [IQR] 150 - 240 minutos), del sangrado transoperatorio fue 97,4 ml (IQR 40 - 100 ml) y de la estancia hospitalaria fue de cutro días (IQR 3 - 5 días). Conclusiones: El MI-TLIF es un procedimiento realizado con gran frecuencia debido a su efectividad y seguridad y que ha demostrado resultados equiparables con el procedimiento abierto. De acuerdo a este estudio la curva de aprendizaje requerida es discretamente mayor que para procedimientos abiertos, alcanzándola aproximadamente tras 45 casos.

Minimally invasive single-door plate laminoplasty with lateral mass screw fixation for the unstable segment. report of two cases with long follow-up / Laminoplastia em porta aberta minimamente invasiva com fixação com parafusos de massa lateral para o segmento instável. relato de dois casos com acompanhamento prolongado / Laminoplastía en puerta abierta mínimamente invasiva y fijación com tornillo de masa lateral para o segmento inestable. reporte de dos casos con seguimiento a largo plazo

ABSTRACT Objective: To report two cases of multilevel cervical spondylotic myelopathy with monosegmental instability, in which we performed a minimally invasive microsurgical transmuscular approach with tubular retractors to create a single-door plate laminoplasty combined with fixation of the unstable segment with lateral mass screws. Methods: The surgical procedures were performed by the senior author. In both patients, the follow-up was performed using the Oswestry Disability Index (ODI), the Visual Analogue Scale for neck and radicular pain (radVAS, neckVAS), the Neck Disability Index (NDI) and the Short Form 36 (SF-36), in the preoperative (preop) and postoperative (postop) periods, and at 1, 3, 6, 12, 18 and 24 months. A radiological evaluation also was performed, which included AP, lateral and flexion-extension films at 6, 12 and 24 months and CT-scan at 12 months. Results: Case 1 - preop ODI: 40%, 24 months postop ODI: 4%; preop radVAS: 7, 24 months radVAS: 0; preop neckVAS: 8, postop 24 months neckVAS: 0; preopNDI: 43%, 24 months PostopNDI: 8%; SF-36 - preop Physical Functioning (PF): 40, preop Vitality (VT): 40, preop Emotional role functioning (RE): 33.3, Bodily pain (BP): 51, General Health (GH): 57, Social Functioning (SF): 75; postop PF: 95, VT: 95, RE: 100, BP: 74, GH: 87, SF: 100. Case 2 - preopODI: 46%, 24 months postopODI: 10%; preop radVAS: 7, 24m radVAS: 0; preop neckVAS: 9, postop 24 months neckVAS: 0; preopNDI: 56%, 24 months PostopNDI: 15%; SF-36 - preop PF: 39, VT: 45, RE: 33.3, BP: 50, GH: 49, SF: 70; postop PF: 90, VT: 100, RE: 100, BP: 82, GH: 87, SF: 100. No complications, cervical instability or signs of failed surgery were found trough and at final follow-up at 24 months. We found significant clinical improvement in both patients. Conclusions: Minimally invasive cervical laminoplasty combined with lateral mass screw fixation for the unstable segment is a useful technique in cases with multilevel cervical spondylotic myelopathy associated with monosegmental instability. Additional comparative studies are needed to establish its efficacy.

RESUMO Objetivo: Relatar dois casos de mielopatia espondilótica cervical em múltiplos níveis com instabilidade de um só segmento, nos quais realizamos uma microcirurgia minimamente invasiva por via transmuscular com retratores tubulares para criar uma laminoplastia em porta aberta com fixação do segmento instável com parafusos de massa lateral. Métodos: Os procedimentos cirúrgicos foram realizados pelo autor principal. Em ambos os pacientes, o acompanhamento foi realizado usando Índice de Incapacidade de Oswestry (ODI), Escala Visual Analógica para dor cervical e radicular (EVAc e EVArad), Índice de Incapacidade Relacionada ao Pescoço (NDI) e o Short Form 36 (SF-36) nos períodos pré-operatório (pré-op) e pós-operatório (pós-op) e em 1, 3, 6, 9, 12, 18 e 24 meses. Realizou-se também a avaliação radiológica, que incluiu vistas AP, laterais e de flexão-extensão aos 6, 12 e 24 meses e TC aos 12 meses. Resultados: Caso 1 - ODI pré-op: 40%, ODI 24 meses pós-op: 4%; pré-op EVArad: 7, EVArad 4 meses: 0; EVAc pré-op: 8, EVAc pós-op 24 meses: 0; NDI pré-op: 43%, NDI pós-op 24 meses: 8%; SF-36 - capacidade funcional (CF) pré-op: 40, vitalidade (VT) pré-op: 40, aspectos emocionais (AE) pré-op: 33,3, dor (D): 51, estado geral da saúde (ES): 57, aspectos sociais (AS): 75; CF : 95, VT: 95, AE: 100, D: 74, ES: 87, AS: 100 pós-op. Caso 2 - ODI pré-op: 46%, ODI 24 meses pós-op: 10%; EVArad pré-op : 7, EVArad 24 meses: 0; EVAc pré-op: 9, EVAc 24 meses pós-op: 0; NDI pré-op: 56%, NDI 24 meses pós-op: 15%; SF-36 pré-op: CF: 39, VT: 45, AE: 33,3, D: 50, ES: 49, AS: 70; CF: 90, VT: 100, AE: 100, D: 82, ES: 87, AS: 100 pós-op. Não houve complicações, instabilidade cervical ou sinais de falha da cirurgia durante o acompanhamento de 24 meses. Ambos os pacientes apresentaram melhoras significativas. Conclusões: A laminoplastia cervical minimamente invasiva combinada com fixação de parafuso de massa lateral do segmento instável é uma técnica útil nos casos com mielopatia espondilótica cervical em vários níveis associada à instabilidade de um só segmento. É necessário realizar estudos comparativos adicionais para estabelecer a eficácia do procedimento.

RESUMEN Objetivo: Relatar dos casos de mielopatía espondilótica cervical en múltiples niveles con inestabilidad de un solo segmento, en los que realizamos una microcirugía mínimamente invasiva por vía transmuscular con retractores tubulares para crear una laminoplastia en puerta abierta con fijación del segmento inestable con tornillos de masa lateral. Métodos: Los procedimientos quirúrgicos fueron realizados por el autor principal. En ambos pacientes, el seguimiento fue realizado usando Índice de Discapacidad de Oswestry (ODI), Escala Visual Analógica para dolor en el cuello y radicular (EVAc y EVArad), Índice de Discapacidad Cervical (NDI) y el Short Form 36 (SF-36) en los períodos preoperatorio (preop) y postoperatorio (posop) y en 1, 3, 6, 9, 12, 18 y 24 meses. Se realizó también la evaluación radiológica, que incluyó proyecciones AP, laterales y de flexión-extensión a los 6, 12 y 24 meses y TC a los 12 meses. Resultados: Caso 1 - ODI preop: 40%, ODI 24 meses posop: 4%; EVArad preop: 7, EVArad 4 meses: 0; EVAc preop: 8, EVAc posop 24 meses: 0; NDI preop: 43%, NDI posop 24 meses: 8%; SF-36 - función física (FF) preop: 40, vitalidad (VT) preop: 40, rol emocional (RE) preop: 33,3, dolor corporal (DC): 51, salud general (SG): 57, función social (FS): 75; FF: 95, VT: 95, RE: 100, DC: 74, SG: 87, FS: 100 posop. Caso 2 - ODI preop: 46%, ODI 24 meses posop: 10%; EVArad preop: 7, EVArad 24 meses: 0; EVAc preop: 9, EVAc 24 meses posop: 0; NDI preop: 56%, NDI 24 meses posop: 15%; SF-36 preop: FF: 39, VT: 45, RE: 33,3, D: 50, SG: 49, FS: 70 preop; FF: 90, VT 100, RE 100, DC 82, SG: 87, FS: 100 posop. No hubo complicaciones, inestabilidad cervical o signos de falla de la cirugía durante el seguimiento de 24 meses. Ambos pacientes presentaron mejoras significativas. Conclusiones: La laminoplastia cervical mínimamente invasiva combinada con fijación de tornillo de masa lateral del segmento inestable es una técnica útil en los casos con mielopatía espondilótica cervical en múltiples niveles asociada a la inestabilidad de un solo segmento. Es necesario realizar estudios comparativos adicionales para establecer la eficacia del procedimiento.