Determinants of Postoperative Spinal Height Change among Adult Spinal Deformity Patients with Long Construct Circumferential Fusion

Methods@#We retrospectively reviewed the clinical and imaging data of ASD patients who underwent lumbar corrective circumferential fusion of ≥3 levels (n=106). SH was defined as the vertical distance between C2 and S1 on a standing lateral image. As potential predictors of postoperative height change, the number of lateral lumbar interbody fusion (LLIF) levels, change in spino-pelvic parameters, total number of levels fused, and pedicle subtraction osteotomies (PSO) were documented. Univariate and multivariate linear regression analyses were performed to identify the predictors of postoperative height change. @*Results@#The mean SH change was −2.39±50.8 mm (range, −160 to 172 mm). The univariate analyses showed that the number of LLIF levels (coefficient=10.9, p=0.03), the absolute coronal vertical axis change (coefficient=0.6, p=0.01), and the absolute Cobb angle change (coefficient=−0.9, p=0.03) were significant predictors for height change. Patients with PSOs (n=14) tended to have a shorter height postoperatively (coefficient=−26.1); however, this difference was not significant (p=0.07). Multivariate analyses conducted with variables of pp=0.04, R2=0.11). @*Conclusions@#Utilizing a modified definition of SH used in previous AIS studies, we demonstrated that patients with ASD lose SH postoperatively and that PT change was an independent contributor of SH change.

Determinants of Postoperative Spinal Height Change among Adult Spinal Deformity Patients with Long Construct Circumferential Fusion

Methods@#We retrospectively reviewed the clinical and imaging data of ASD patients who underwent lumbar corrective circumferential fusion of ≥3 levels (n=106). SH was defined as the vertical distance between C2 and S1 on a standing lateral image. As potential predictors of postoperative height change, the number of lateral lumbar interbody fusion (LLIF) levels, change in spino-pelvic parameters, total number of levels fused, and pedicle subtraction osteotomies (PSO) were documented. Univariate and multivariate linear regression analyses were performed to identify the predictors of postoperative height change. @*Results@#The mean SH change was −2.39±50.8 mm (range, −160 to 172 mm). The univariate analyses showed that the number of LLIF levels (coefficient=10.9, p=0.03), the absolute coronal vertical axis change (coefficient=0.6, p=0.01), and the absolute Cobb angle change (coefficient=−0.9, p=0.03) were significant predictors for height change. Patients with PSOs (n=14) tended to have a shorter height postoperatively (coefficient=−26.1); however, this difference was not significant (p=0.07). Multivariate analyses conducted with variables of pp=0.04, R2=0.11). @*Conclusions@#Utilizing a modified definition of SH used in previous AIS studies, we demonstrated that patients with ASD lose SH postoperatively and that PT change was an independent contributor of SH change.

Artrodesis intersomática lateral de columna lumbar: Técnica quirúrgica y conceptos actuales / Lateral lumbar interbody fusion. Surgical technique and current concepts

El abordaje lateral mínimamente invasivo de columna lumbar para la artrodesis intersomática es una técnica relativamente nueva y ha conseguido resultados prometedores en los pacientes con diferentes patologías de la columna lumbar. Es una técnica segura que proporciona un adecuado soporte estructural entre los platillos vertebrales, puede corregir la deformidad en los planos coronal y sagital, y ejercer una descompresión indirecta del canal raquídeo respetando los elementos posteriores. La evidencia sobre esta técnica ha ido creciendo y diversificándose en los últimos años, se han comunicado nuevas indicaciones, y resultados a mediano y largo plazo. El propósito de este trabajo es detallar el procedimiento quirúrgico paso a paso, con sus variantes tal como lo realizamos en nuestros Centros, y puntualizar los conceptos actuales basados en una revisión bibliográfica. Nivel de Evidencia: IV

Minimally invasive lateral approach for lumbar interbody fusion is a relatively new technique and has shown promising results in patients with different spine disorders. It is a safe technique, provides adequate structural support between vertebral plates, and it can correct coronal and sagittal plane deformity and apply an indirect nerve decompression avoiding posterior elements. In recent years, experience with this approach has increased; new indications and medium- and long-term results were reported. The purpose of this work is to explain step-by-step surgical procedure and its variants as they are performed in our centers, and to point out current concepts based on a bibliographic review. Level of Evidence: IV

Serotonergic Antidepressants Are Associated with Increased Blood Loss and Risk for Transfusion in Single-Level Lumbar Fusion Surgery

STUDY DESIGN: Retrospective case-control study. PURPOSE: The purpose of this study was to examine the effect of antidepressants on blood loss and transfusion requirements in spinal surgery patients. OVERVIEW OF LITERATURE: Several studies have shown an increase in perioperative bleeding in orthopedic surgery patients on antidepressant drug therapy, yet no study has examined the impact of these agents on spinal surgery patients. METHODS: Charts of patients who underwent single-level spinal fusion (posterior lumbar interbody fusion with posterior instrumentation) performed by five fellowship-trained surgeons at a tertiary spine center between 2008 and 2013, were retrospectively reviewed. Exclusion criteria included select medical comorbidities, select drug therapy, and Amercian Society of Anesthesiologists Physical Status Classification score of greater than 2. Serotonergic antidepressants were examined in multivariate analysis to assess their predictive value on estimated blood loss and risk of transfusion. RESULTS: A total of 235 patients, of which 52% were female, were included. Allogeneic blood was transfused in 7% of patients. The average estimated blood loss was 682±463 mL. Selective serotonin reuptake inhibitors were taken by 10% of all patients. Multivariable regression analysis showed that intake of selective serotonin reuptake inhibitors was a significant predictor for blood loss (average increase of 34%, p=0.015) and for the need of allogeneic blood transfusion (odds ratio, 4.550; p=0.029). CONCLUSIONS: There was a statistically significant association between selective serotonin reuptake inhibitors and both increased blood loss and risk of allogeneic red blood cell transfusion. Surgeons and perioperative providers should take these findings into account when assessing patients' preoperative risk for blood loss and transfusion.

A Comparative Study of Lateral Lumbar Interbody Fusion and Posterior Lumbar Interbody Fusion in Degenerative Lumbar Spondylolisthesis

STUDY DESIGN: Level 4 retrospective review. PURPOSE: To compare the radiographic and clinical outcomes between posterior lumbar interbody fusion (PLIF) and lateral lumbar interbody fusion (LLIF) with posterior segmental spinal instrumentation (SSI) for degenerative lumbar spondylolisthesis. OVERVIEW OF LITERATURE: Both PLIF and LLIF have been performed for degenerative spondylolisthesis with good results, but no study has directly compared these two techniques so far. METHODS: The electronic medical and radiographic records of 78 matched patients were analyzed. In one group, 39 patients underwent PLIF with SSI at 41 levels (L3-4/L4-5), while in the other group, 39 patients underwent the LLIF procedure at 48 levels (L3-4/L4-5). Radiological outcomes such as restoration of disc height and neuroforaminal height, segmental lumbar lordosis, total lumbar lordosis, incidence of endplate fracture, and subsidence were measured. Perioperative parameters were also recorded in each group. Clinical outcome in both groups was assessed by the short form-12, Oswestry disability index and visual analogue scale scores. The average follow-up period was 16.1 months in the LLIF group and 21 months in the PLIF group. RESULTS: The restoration of disc height, foraminal height, and segmental lumbar lordosis was significantly better in the LLIF group (p<0.001). The duration of the operation was similar in both groups, but the average blood loss was significantly lower in the LLIF group (p<0.001). However, clinical outcome scores were similar in both groups. CONCLUSIONS: Safe, effective interbody fusion can be achieved at multiple levels with neuromonitoring by the lateral approach. LLIF is a viable treatment option in patients with new onset symptoms due to degenerative spondylolisthesis who have had previous lumbar spine surgery, and it results in improved sagittal alignment and indirect foraminal decompression.

Dosis elevadas de aspirina disminuyen la natriuresis en hipertensos tratados con enalapril / High doses of aspirin reduce natriuresis in hypertensive patients treated with enalapril

Los inhibidores de la enzima convertidora de la angiotensina (IECA) han demostrado ser eficases en el tratamiento de la hipertensión arterial. Sin embargo, una importante proporción de hipertensos recibe además antiagregación plaquetaria con ácido acetil salicílico (AAS), y la consecuente inhibición de la síntesis de prostaglandinas con AAS atenuaría el efecto vasodilatador y la mayor excreción urinaria de sodio (Na(u)) atribuidas al IECA. Nuestro objetivo fue evaluar la interacción de dos dosis de AAS (81 y 325 mg/día) sobre el efecto hipotensor del enalapril y el impacto sobre la excreción de (Na(u)) en pacientes hipertensos. Se incluyeron 22 pacientes de ambos os sexos, entre 35 y 65 años. Todos reciberon enalapril, dieta hiposódica y, secuencialmente separadas por período de (wash out), las dos dois de AAS durante los setenta días del estudio. Se evaluó: presdión arterial sistólica (PAS), diastólica (PAD), media (PAM) y (Na(u)) en un período basal (PB), con 325 y 81 mg de AAS (P1 y P2 respectivamente). Comparando el PB con P1 y P2, se observó una reduccíon significativa de la PAS, PAD, PAM (p<0.01). Al comparar la PAS, PAD, PAM entre P1 y P2, no hubo diferencias significativas. La (Na(u)) en el PB fue mayor (p<0.01)con respecto al P1 y P2, y también P2 con respecto a P1. Estos resultados sugieren que en una población de pacientes hipertensos esenciales tratados con elapril y diferentes dosis de AAS, el tratamiento con dosis bajas de AAS está asociado a mejor control de la PA y mayor eliminación de sodio urinario.

Nucleotomía percutánea aspirativa: evaluación de sus indicaciones y resultados

Existen en la actualidad diversas maneras de tratamiento para las hernias discales, que van desde las formas más conservadoras hasta las intervenciones quirúrgicas. En el año 1975, el Dr. Hijikata describe un método que permite la escisión del núcleo pulposo en forma percutánea. Años más tarde, en 1984, el Dr. Onik y colaboradores perfeccionan dicha técnica y crean la nucleotomía percutánea automática, que renueve el contenido del disco utilizando una bomba aspirativa. La nucleotomía percutánea aspirativa constituye una forma terapéutica en la que la resección del núcleo pulposo se obtiene bajo anestesia local, con mínimo sangrado y sin lesión de otras estructuras importantes, para mantener la estabilidad de la columna vertebral. No requiere internación y permite una rápida rehabilitación. Sin embargo, su uso está restringido a determinadas características del paciente en general y del disco en particular, y se debe ser muy estricto al indicarla. Siguiendo estos conceptos, se llevaron a cabo 87 intervenciones, de las cuales 72 tuvieron una evolución excelente o buena (83 por ciento). Creemos que es una alternativa terapéutica para tener en cuenta debido a su plasticidad, mínima agresividad y muy buenos resultados dentro de una indicación limitada

Monoclonal antibodies to bovine parathyroid hormone: production and characterization

1. This paper describes the production and characterization of monoclonal monoclonal antibodies against bovine parathyroid hormone (bPTH) - (1-84). 2. Spleen cells from A/J mice successfully immunized with bPTH-(1-84) were fused with SP2/O myeloma cells using PEG 4000 as fusogen. The screening method employed microtiter plates coated with sheep antimouse IgG and the presence of specific monoclonal antibodies was demonstrated by the binding of 125I-bPTH-(1-84). 3. A delailed study of the specificity of the three viable monoclonals with highest affinity showed that two (6FH6 and 6CD4) were amino-terminal specific and the other (5BG9) carboxyl-terminal specific. The two amino-terminal monoclonal antibodies appear to recognize the same antigenic site. 4. The monoclonal antibodies produced are potentially useful reagents for the development of new methods for the measurement of PTH in biological fluids, studies on the interaction of PTH with its receptor, as well as localization of PTH producing cells

Characterization of a high-affinity antiserum specific for the amino-terminal sequence of human parathyroid hormone

1. The present paper describes a detailed study of the specificity of high-affinitu antibodies obtained from the yolk of eggs laid by achicken successfully immunized with synthetic human parathyroid hormone (hPTH)-(1-34). 2. Using 125I-labelled bovine parathyroide hormone (bPTH)-(1-84) puridied by high performance liquid chromatography (HPLC) as tracer, and hPTH-(1-34) as reference, we found superimposable curves with hPTH-(13-34), bPTH-(13-34) and bTH-(1-34); the [Asp-76]hPTH-(1-84) peptide showed a molar percent cross-reactivity (calculated at 50% B/BO) of 73% and the bovine sequence 1-84 of 15%. 3. Studying amidated [Tyr-34] bovine PTH fragments we found the highest cross-reactivity with the peptide 7-34 (1.7%) and 25-34 (0.4%). The bovine sequence 1-25 showed a low reactivity (0.7%) and the 1-12 sequence none at all . Rat parathyroid hormone (rPTH)- (1-34) showed low cross-reactivity (3.1%), the same occuring with peptide [Tyr-34, Norleu-8,18]bPTH-(1-34) (1.5%). 4. The data suggest that the antibodies studied recognize epitopes in or near amino acids 18 to 25 of the sequence of the hPTH molecule. This region of the molecule is coincident with the antigenic determinant predicted by the abalysis of the hydrophilicity plot of the hPTH-(1-34) peptide