Ensaios mecânicos de um sistema de fixação pedicular com barra transversal Mechanical assay of a pedicular fixation system with transversal rod

Foi realizado estudo biomecânico de um protótipo de sistema de fixação vertebral que utiliza o pedículo vertebral como ponto de ancoragem dos implantes, associado a hastes que conectam transversalmente os parafusos pediculares. De modo diferente dos sistemas convencionais, nos quais os parafusos são conectados no sentido longitudinal, no sistema desenvolvido as hastes são conectadas transversalmente aos parafusos. Foram realizados ensaios mecânicos (flexo-compressão, flexão lateral e torção) utilizando-se corpos de prova de madeira em máquina universal de testes, com a finalidade de comparar a resistência desse sistema de fixação com o sistema convencionalmente utilizado. Os testes biomecânicos mostraram que o sistema desenvolvido apresentou menor resistência nos ensaios mecânicos realizados, quando comparado com o sistema de fixação convencional.<br>A biomechanical study of a spine fixation prototype was performed. This system uses vertebral pedicle as anchor point of the implants in association with transversally connecting rods. This is different form the usual systems where longitudinally placed rods connect the pedicular screws. Mechanical assays were performed (flexo-compression, lateral flexion, torsion) using probe wood pieces in an universal testing machine, aiming to compare the resistance of this system of fixation to the conventionally used ones. Biomechanical tests showed that the system was less resistant to the mechanical assays when compared to conventional systems

Hybrid decompression technique and two-level corpectomy are effective treatments for three-level cervical spondylotic myelopathy

The optimal surgical strategy for multilevel cervical spondylotic myelopathy (CSM) has not been defined, and few comparative researches between hybrid decompression and multilevel corpectomy have been conducted. Here, we reported 28 patients of three-level CSM, of whom 12 underwent hybrid decompression and 16 two-level corpectomy, with each type of procedure chosen according to radiologic characteristics of those patients. Clinical and radiologic parameters of both groups showed various degrees of improvement. However, no statistically significant differences in Japanese Orthopedic Association (JOA) score improvement rate, graft fusion rate, post-operative neck disability index (NDI) or segmental lordosis between the two groups were found. We conclude that both hybrid decompression and two-level corpectomy could obtain satisfying clinical efficacy in the management of three-level CSM for appropriate patients