Estudo morfométrico do pedículo das vértebras lombares

Abstract

Foi realizado estudo morfométrico de dez segmentos de coluna lombar de cadáveres adultos de ambos os sexo com a finalidade de estudar parâmetros relacionados com a morfometria dos pedículos da coluna lombar. Os pedículos foram seccionados transversalmente de ambos os lados na altura do seu menor diâmetro. As vértebras foram fotografadas e o estudo morfométrico foi realizado em aparelho Minimop, tendo sido avaliados bilateralmente: o formato do pedículo, o diâmetro, a espessura das paredes corticais, a área do pedículo, a área do osso cortical, a área de osso esponjoso, e a porcentagem de osso esponjoso e cortical do pedículo. O pedículo vertebral da coluna lombar apresenta forma oval, o diâmetro vertical é maior que o horizontal, a cortical medial é mais espessa, a área do pedículo aumenta no sentido crânio cauda, e a relação entre a área de osso cortical e esponjoso é constante em toda a extensão da coluna lombar.

Implementing “Free-Hand” Technique Training for Pedicle Screw Instrumentation in Neurosurgical Residency

“…From T8 to L5 the pedicle diameter grows progressively and the rates of pedicle violation diminishes accordingly. 6,7 Anterior violations in the lumbar spine are much less dangerous since abdominal viscerae are usually not fixed to the anterior longitudinal ligament, except in lumbosacral transition. In our series there was only one critical anterior violation in the lumbosacral region -in such case the pedicle screw touched the posterior wall of the rectum, without perforating it.…”

“…During the last years, several anatomic studies have been performed in order to detail the complex morphometry and threedimensional anatomy of thoracolumbar pedicles. 4,6,7 Besides, the already known improvement in accuracy of pedicle screw placement through "Free-hand" technique with training 1 has created the necessity of proper anatomic models for surgical practice, as well as objective forms of assessment of the accuracy of the final obtained results. The creation of such simulative scenarios for surgical practicing are crucially important, and the implementation of this training on neurosurgical residency requires multidisciplinary partnerships among educators, anatomy and radiology departments, as well as technical support from spine surgery companies.…”

"Free-hand" technique for thoracolumbar pedicle screw instrumentation: Critical appraisal of current "State-of-Art"

“…From T8 to L5, the pedicle diameter grows progressively and the rates of pedicle violation diminishes accordingly. [11,9] Anterior violations in the lumbar spine are much less dangerous Once abdominal viscerae are usually not fixed to the anterior longitudinal ligament, except in lumbosacral transition [ Figure 7b]. …”

“…In the last few years several anatomic studies have been performed to detail the complex morphometry and three-dimensional anatomy of the lumbar pedicles. [9][10][11] In the lumbar spine an osteotomy (partial facetectomy of the infero-lateral one-third of the inferior articular process of the superior vertebrae is usually performed for three reasons: It enables the identification of the exact limit between the superior and inferior articular processes; it facilitates the correct identification of the ideal initial perforation site; it decreases the amount of cortical bone (which may make the initial perforation difficult, specially in the presence of hypertrophic facets); and finally it provides a smooth bony surface for final allocation of the head of the screw. The entry point is in the intersection between a line that passes just laterally to the inferior articular process and a line which bisects the transverse process.…”

Avaliação tomográfica do posicionamento de parafusos pediculares em deformidades na coluna torácica e lombar introduzidos com base na técnica "free hand"

“…A imprecisão na inserção de parafusos pediculares, além de reduzir a estabilidade do sistema, pode ocasionar dano neurológico, vascular e visceral 5 . Assim, o cirurgião procura utilizar recursos que permitam identificar adequadamente o seu ideal posicionamento, o que inclui referenciais anatômicos, estudos de radiologia simples, radioscopia, tomografia computadorizada e navegação estereotáxica 1,6 .…”