Cambios en la lordosis lumbar luego de una artrodesis vertebral posterior de la columna torácica y su relación con la incidencia pelviana / Changes in lumbar lordosis after further spinal fusion of thoracic spine and its relationship to pelvic incidence

Objetivo: Evaluar las variables del plano sagital en pacientes con escoliosis idiopática del adolescente tratados mediante una artrodesis vertebral posterior instrumentada con tornillos pediculares y establecer relaciones entre ellas. Materiales y Métodos: Se evaluó retrospectivamente a 20 pacientes. Se compararon los cambios en la lordosis cervical, la cifosis torácica, la lordosis lumbar, la incidencia pelviana, el balance sagital global y la cifosis de la unión proximal en los espinogramas preoperatorio, posoperatorio inmediato y a los dos años de la cirugía. Se correlacionaron los cambios en la lordosis lumbar con la cifosis torácica y la incidencia pelviana. Resultados: Se observó una disminución significativa en la cifosis torácica y en la lordosis lumbar en el espinograma posoperatorio inmediato. Ambos parámetros mostraron un aumento en el espinograma a los dos años. Se halló un aumento significativo en la cifosis de la unión proximal y en la lordosis cervical entre el preoperatorio y el posoperatorio a los dos años. La única correlación posoperatoria significativa fue entre la lordosis lumbar y la incidencia pelviana en el espinograma a los dos años de la cirugía. Conclusiones: La artrodesis vertebral posterior instrumentada con tornillos pediculares en curvas Lenke 1 provoca una reducción posoperatoria de la cifosis torácica y de la lordosis lumbar, y un aumento posoperatorio de la lordosis cervical y de la cifosis de la unión proximal. A los dos años, se observó un aumento de la lordosis lumbar no instrumentada, y que dicha lordosis lumbar se correlaciona significativamente con la incidencia pelviana.

Objective: To evaluate the sagittal profile variables in patients with adolescent idiopathic scoliosis who underwent selective thoracic posterior spinal instrumentation and fusion with pedicle screws and to determine relationships among them. Methods: Twenty consecutive patients were retrospectively evaluated. Changes in cervical lordosis, thoracic kyphosis, proximal junctional kyphosis, lumbar lordosis, pelvic incidence and global sagittal balance were compared in standing lateral radiographs performed before surgery, at the immediate postoperative period, and two years after surgery. Changes in postoperative lumbar lordosis were correlated with changes in thoracic kyphosis and pelvic incidence. Results: There was a significant decrease in thoracic kyphosis and lumbar lordosis between preoperative and immediate postoperative radiographs, but both parameters showed an increase in the radiographs two years later. A significant increase in proximal junctional kyphosis and cervical lordosis was also found between preoperative and 2-year postoperative radiographs. The only significant postoperative correlation found was between lumbar lordosis and pelvic incidence at 2-year follow-up control. Conclusions: Posterior spinal instrumentation and fusion with pedicle screws in Lenke type 1 deformities reduces thoracic kyphosis and lumbar lordosis, and increases cervical lordosis and proximal junctional kyphosis. Uninstrumented lumbar lordosis increased at 2-year follow-up and it is strongly related to the pelvic incidence.

Análisis con resonancia magnética de la posición de la amígdala cerebelosa antes de la corrección instrumentada por vía posterior y después de ella en pacientes con escoliosis idiopática del adolescente / Magnetic resonance imaging evaluation of the position of the cerebellar tonsil before and after posterior spinal fusion in adolescent idiopathic scoliosis

Objetivo: Analizar, con resonancia magnética, las variaciones de posición de la amígdala cerebelosa, antes de corregir la deformidad espinal mediante una artrodesis vertebral posterior instrumentada y después, en pacientes con escoliosis idiopática del adolescente sin sintomatología neurológica. Materiales y Métodos: Se evaluaron retrospectivamente 40 pacientes con escoliosis idiopática del adolescente, sin síntomas neurológicos y sometidos a una artrodesis vertebral posterior instrumentada para corregir la deformidad espinal. A todos se les realizó una resonancia magnética de la fosa cerebral posterior y de la columna cervical, antes de la cirugía espinal y después de ella. Resultados: La magnitud preoperatoria promedio de la curva escoliótica fue de 53,15° y la de la cifosis torácica fue de 35,42º. En el posoperatorio inmediato, la magnitud promedio fue de 7,45º y de 27,87º,respectivamente. El valor promedio de la longitud de la columna en el plano coronal fue de 44,5 cm en el preoperatorio y de 48,27 cm en el posoperatorio. El valor promedio de la longitud de la columna vertebral en el plano sagital fue de 50,87 cm en el preoperatorio y de 55,13 cm en el posoperatorio. No se observó unadiferencia significativa respecto de la posición de la amígdala cerebelosa en las mediciones antes de corregir la deformidad espinal y después (p = 0,6042). Conclusión: No se observó una variación significativa en la ubicación de la amígdala cerebelosa respecto del agujerooccipital en pacientes con escoliosis idiopática del adolescente que fueron sometidos artrodesis vertebral posterior instrumentadapara corregir la deformidad espinal.

Objective: To evaluate variations in cerebellar tonsil position after posterior spinal fusion in neurologically intact patients with adolescent idiopathic scoliosis. Methods: We retrospectively evaluated 40 patients with adolescent idiopathic scoliosis and no neurological symptoms that underwent posterior spinal fusion. Anteroposterior and sagittal standing radiographs, and sagittal hindbrain MRI wereperformed in all patients before and after spinal surgery. We evaluated variations in cerebellar tonsil position in relation to spinal correction and spinal elongation after posterior spinal fusion. Results: Mean preoperative magnitude of the curve was 53.15° and thoracic kyphosis was 35.42º. Mean postoperative valueswere 7.45º and 27.87º, respectively. The average length of the spine in the coronal plane was 44.5 cm in preoperative x-rays and 48.27 cm in postoperative x-rays. The average length in the sagittal plane was 50.87 cm in preoperative x-raysand 55.13cm in postoperative x-rays. There was no significant difference in theposition of the cerebellar tonsil before and after spinal correction (p = 0.6042). Conclusion: Position of the cerebellar tonsil did not change with posterior spinal fusion in patients with adolescent idiopathic scoliosis.

Posterior-only spinal fusion without rib head resection for treating type I neurofibromatosis with intra-canal rib head dislocation

OBJECTIVES: Patients with Type I neurofibromatosis scoliosis with intra-canal rib head protrusion are extremely rare. Current knowledge regarding the diagnosis and treatment for this situation are insufficient. The purpose of this study is to share our experience in the diagnosis and surgical treatments for such unique deformities. METHODS: Six patients with Type I neurofibromatosis scoliosis with rib head dislocation into the spinal canal were diagnosed at our institution. Posterior instrumentation and spinal fusion without intra-canal rib head resection via a posterior-only approach was performed for deformity correction and rib head extraction. The efficacy and outcomes of the surgery were evaluated by measurements before, immediately and 24 months after the surgery using the following parameters: coronal spinal Cobb angle, apex rotation and kyphosis of the spine and the intra-canal rib head position. Post-operative complications, surgery time and blood loss were also evaluated. RESULTS: Patients were followed up for at least 24 months post-operatively. The three dimensional spinal deformity was significantly improved and the intra-canal rib head was significantly extracted from the canal immediately after the surgery. At follow-up 24 months after surgery, solid fusions were achieved along the fusion segments, and the deformity corrections and rib head positions were well maintained. There were no surgery-related complications any time after the surgery. CONCLUSIONS: Systematic examinations are needed to identify patients with Type I neurofibromatosis scoliosis with rib head dislocation into the canal who can be treated by posterior-only spinal fusion without rib head resection. .

The Effect of Low Dose Aprotinin in Patients with Adolescent Idiopathic Scoliosis Undergoing Posterior Spinal Fusion

BACKGROUND: Aprotinin is a kallikrein inhibitor at high doses and a plasmin inhibitor at low doses. Low-dose aprotinin has been shown to reduce transfusion requirements in patients undergoing liver resection, open-heart surgery, and spine deformity surgery. The aim of this study was to evaluate the effect of low-dose aprotinin on perioperative blood loss and on transfusion requirements in adolescent idiopathic scoliosis (AIS) patients undergoing posterior spinal fusion. METHODS: We studied forty patients who were set to undergo posterior spinal fusion. Twenty patients were given aprotinin, and twenty control patients were not given aprotinin. Patients were assessed for pre- and post-operative hemoglobin, hematocrit, platelet count, blood urea nitrogen, and creatinine. Perioperative blood loss was measured through suction drains and gauze, and transfusion requirements were recorded. RESULTS: Upon comparing the aprotinin and control groups, we found no differences in intraoperative blood loss (1,456 +/- 622 ml vs 1,625 +/- 738 ml, respectively, [P = 0.17]), total (intraoperative and 24 h postoperative) blood loss (2,544 +/- 977 ml vs 2,594 +/- 783 ml, respectively, [P = 0.42]), or homologous transfusion requirements (1,672 +/- 1,077 ml vs 1,520 +/- 718 ml packed RBCs, respectively, [P = 0.52]). Renal function was maintained in both groups. CONCLUSIONS: Low-dose aprotinin does not decrease blood loss or transfusion requirements in AIS patients undergoing posterior spinal fusion. Renal function was maintained in both the aprotinin and control groups.

Effect on the spine growth of the immature rabbits at different month-age with posterior spinal fusion (experimental research on crankshaft phenomenon of spine) / 中国矫形外科杂志

[Objective]To explore the effect on spinal growth and devetopment at different month-age of immature rabbits with spinal fusion and fixation;and to explain the mechanism of crankshaft phenomenon after child scoliosis treatment.[Method]Twenty-four 6-weeks-old rabbits and 24 15-weeks-old rabbits were randomly divided into 2 groups.Various lengths of lumbar vertebral region were fused posteriorly and fixed with wires,and the Cobbs angle in the frontal and saglttal planes were measured after the surgery.[Result]The lumbar spine of each group became lordosis with different degree.It was most obvious in the group which were fused in 7 lumbar vertebraes at 6-month-week age.The multiple linear regression outcomes show significance among different month-age,different lengths of fusion region and the Cobbs angle.[Conclusion]In the imature rabbits,if their lumbar vertebrae were posteriorly fixed only may be appeared and getting serious gradually due to the potential growth of anterior spinal column.There has significant correlation among the degree of skelecton immature,fused segment length and spine lordosis.

Posterior Spinal Fusion using Autogenous Bone Graft Combined with Xenograft for the Treatment of Thoracolumbar Spine Fractures / 대한정형외과학회잡지

PURPOSE: To evaluate the clinical outcome and reliability of mixed bone in the process of posterior spinal fusion for the treatment of thoracolumbar spine fractures. In order to eliminate donor site morbidity which is linked to the use of autogenous bone graft, a new surgical procedure mixing autogenous bone chips that were obtained from local decortication of the posterior element of the spine with highly purified calf bone (Lubboc) is studied. MATERIALS AND METHODS: We followed up 9 patients who had undergone autogenous bone graft and 9 patients who had undergone mixed bone graft for more than 12 months out of 33 patients who underwent posterior spinal fusion for thoracolumbar spine fractures between July 1993 and July 1997. RESULTS: Radiographic results indicated solid bony union in 17 of 18 cases regardless of the graft materials. Based on each follow-up evaluation, it was found that the increase in kyphotic angle was related to elapsed time rather than to the type of graft materials. CONCLUSIONS: It appears that the new surgical method of bone graft with highly purified calf bone can be a reliable alternative for achieving stable posterior spinal fusion as long as bone chips large enough to fill the interlamina space can be obtained.