Pedicle screws are widely used in spinal surgeries, but it remains technically demanding to place. There are numerous studies on the anatomy of pedicle; however, there is very little insight on the relationship between the pedicle and the spinous process, which is an important part of the spinal posterior column.The aim of the study was to investigate the radiographic anatomical relationship be...

The pig spine is widely used as a large animal model for preclinical research in human medicine to test new spinal implants and surgical procedures. Among them, pedicle screw is one of the most common method of fixation of those implants. However, the pedicle of the porcine vertebra is not as well defined and not as large as the pedicle of the human vertebra. Therefore, the position of the scre...

BACKGROUND The use of pedicle screws is the gold standard for supplemental posterior fixation in lateral interbody fusion. Information about the performance of transfacet pedicle screws compared to standard pedicle screws and rods in the upper lumbar spine with or without a lateral interbody fusion device in place is limited. METHODS Fifteen fresh frozen human cadaveric lumbar spine segments ...

The incidence of pedicle screw breech varies based on anatomic location, body habitus, surgeon experience, spinal deformity, and surgical technique. Pedicle breeches have been reported to occur in up to 40% of screws. The purpose of this retrospective study was to compare the rates of revision of pedicle screw placement when using intraoperative C-arm vs O-arm (Medtronic, Memphis, Tennessee) as...

The intralaminar screw construct has been recently introduced in C6-C7 fixation. The aim of the study is to compare the stability afforded by three different C7 posterior fixation techniques using a three-dimensional finite element model of a C6-C7 cervical spine motion segment. Finite element models representing three different cervical anchor types (C7 intralaminar screw, C7 lateral mass scre...

The earliest growth of post-metamorphic (postlarval) shells in two species of Eohadrotreta is described from the Cambrian Shuijingtuo Formation of South China. Two different growth patterns can be observed by quantifying developmental variations in size and shape of successive stages of post-metamorphic shell growth (including the pedicle foramen forming stage, pedicle foramen enclosing stage a...

INTRODUCTION: In a pedicle screw fixation, the degree of osseointegration between a screw and the bone is an essential factor for the stability and fusion. In patients with osteoporosis, however, there is a high possibility for a pedicle screw loosening. Owing to this, there is a difficulty in determining the surgical indications. Previous biomechanical studies have reported that a pedicle scre...

Introduction: Despite widespread use of pedicles in lumbar spine fixation, relatively little is known regarding variations in pedicle structure particularly in osteoporosis. It is valuable to understand this relationship because pedicles provide an important area for screw fixation and a point of complication when screws penetrate through weak pedicle walls into adjacent structures. Hirano et a...

A cortical bone graft on a muscle pedicle was taken from the ulna and transferred to bridge a complete defect of the radius in 16 dogs. In 14 control dogs a free graft was used, that is, one without a muscle pedicle. Union in the group with pedicle grafts was far superior to that in the group with free grafts, mainly because in those with pedicle grafts there was good subperiosteal new bone for...

The use of pedicle screw instrumentation in the spine has evolved over the last two decades. The initial use of pedicle screws began in the lumbar spine. As surgeons have become more comfortable with the complex anatomy required for accurate screw placement, the use of pedicle instrumentation has evolved to include their use in the thoracolumbar and thoracic spine. The impetus behind their incr...