RESUMEN
Introducción: Como la cifosis toracica y la lordosis cervical son directamente proporcionales, las modificaciones del plano sagital toracico impactarian sobre la columna cervical. Nuestro objetivo fue detectar cambios en el plano sagital cervical, a corto y mediano plazo, durante el tratamiento quirurgico segun una tecnica posterior. Materiales y Métodos: Estudio retrospectivo radiografico de tipo serie de casos, entre enero de 2005 y abril de 2009. Criterios de inclusion: escoliosis idiopatica del adolescente Lenke 1, tratamiento por via posterior con tornillos transpediculares. Seguimiento minimo 2 anos. Parametros analizados: nivel Cobb, nivel de instrumentacion proximal, densidad de implantes, lordosis cervical, cifosis toracica proximal, cifosis toracica principal, inclinacion sagital T1, balance sagital global, balance sagital cervical. Analisis estadistico mediante ANOVA de muestras repetitivas y Tukey, con el programa Graph-Pad-Prism. Resultados: 25 pacientes. Seguimiento promedio 4,3 anos. Cifosis toracica: media preoperatoria 26,8o, posoperatoria 20,6o. Efecto lordotizante despues del tratamiento quirurgico (p ≤0,001). La inclinacion sagital T1 y la cifosis proximal T2-T5 (p ≤0,038) mostraron un incremento hacia el ultimo control. El 72 % presentaba rectificacion o cifosis cervical antes de la cirugia. El 44 % experimento una mejoria hacia el ultimo control. Los niveles de artrodesis mas altos se correlacionaron con los casos que empeoraron su contorno sagital posoperatorio. Conclusiones: Nuestra tecnica de correccion genero un efecto lordotizante toracico. Esto se tradujo, a mediano plazo, en un incremento de la retropulsion del tronco y rectificacion o perdida de la lordosis a nivel cervical...
Background: As thoracic kyphosis and cervical lordosis are proportionally related, every change in the thoracic sagittal plane will impact on the cervical alignment. Our objective was to detect changes in the sagittal cervical plane at short- and medium term follow-up during surgical treatment, according to the posterior technique. Methods: Retrospective, radiographic case series study performed between January 2005 and April 2009. Inclusion criteria: Lenke type 1 adolescent idiopathic scoliosis, and posterior screw fixation surgery. Radiographic parameters: Cobb angle, uppermost instrumented vertebra, implant density, cervical lordosis, proximal thoracic kyphosis, main thoracic kyphosis, T1 sagittal tilt, global sagittal balance and cervical sagittal balance. Statistical analysis: ANOVA of repetitive samples and Tukey, using the Graph-Pad-Prism. Results: 25 patients. Mean follow-up 4.3 years. Thoracic kyphosis (T5-T12): average, preoperative 26.8º and 20.6º postoperative. Lordosing effect after surgical treatment (p ≤0.001). T1 sagittal tilt and T2-T5 proximal thoracic kyphosis (p ≤0.038) tended to increase at last control. Seventy two per cent of our sample showed rectification or even cervical kyphosis before surgery. Only 44 % had certain better alignment at the last follow-up. Higher UIV correlated with a worse cervical plane alignment after surgery. Conclusions: Our derotational concavity technique with poliaxial pedicle screws and titanium 5.5 rod demonstrated a lordosing effect in the thoracic sagittal plane. This was translated into a trunk retropulsion and rectification or lost of lordosis in the sagittal cervical plane in the medium-term follow-up...