BACKGROUND Incorrect placement of pedicle screws may lead to neurovascular injury, so the position is important for the reduction of spinal fractures. CT-based image-guided surgery has been promoted as a means to theoretically improve the accuracy of pedicle screw placement. Patients who underwent CT-based navigation-assisted pedicle screw fixation for thoracic or lumbar fractures were reviewed...

BACKGROUND It has been recently observed that in implants with screw-retained abutments, in in vitro as well as in vivo conditions, bacteria can penetrate inside the internal cavity of the implant as a consequence of leakage at the implant-abutment interface. An alternative to screw-retained abutments is represented by implants that can receive cemented abutments. In this case, the abutment goe...

BACKGROUND Pedicle screw instrumentation is widely used for spinal stabilization. However, the accuracy for free-hand screw placement ranges from 69% to 94%. This study assesses the value of the existing classification systems, and investigates their impact on the ability to assess the accuracy of free-hand screw placement. METHODS Data were collected retrospectively from the medical records ...

In some scenarios, such as complex revisions or tumor cases, intralaminar screw placement in the upper thoracic spine can be used to supplement or replace traditional pedicle screw placement. Despite the theortic feasibility of placing these screws, no thorough anatomic study has evaluated the morphology of the T1 lamina for screw placement.Anatomic data of the T1 lamina, including height, widt...

Purpose In situ fixation for mild to moderate slipped capital femoral epiphysis (SCFE) remains an acceptable treatment methodology in most centers. Satisfactory fixation results have been reported with the procedure using either the fracture table or radiolucent table, both of which allow the hip to be imaged during the procedure. The position of the pin within the center of the femoral head is...

PURPOSE To investigate the effect of lag-screw positions in the femoral head on modes of fixation failure. METHODS 591 patients aged 65 years or older underwent sliding compression screw fixation for type A(1) (n=249) and type A(2) (n=342) intertrochanteric fractures of the femur after low-energy injuries. There were 18 cases of fixation failure; in 13 (group 1) the lag screw was placed in th...

PURPOSE To study the anatomy of the pubic ramus and adjacent structures in 160 Japanese to establish a safer pubic screw fixation technique. METHODS 80 male and 80 female Japanese aged 16 to 89 (mean, 50) years (10 persons in each decade of age) underwent 3-dimensional computed tomographic scanning of their pelvises. The angle at which the screw should be targeted, the appropriate length of t...

INTERTROCHANTERIC FRACTURES Approximately 50% of intertrochanteric fractures are stable and have minimal or no posteromedial comminution. The remaining 50% are unstable and have posteromedial instability and little resistance to varus deformity.1,4,5 Older rigid devices led to cutout or penetration of the nail as the fracture impacted. In the late 1960s, sliding devices were developed to allow ...

The authors performed a cadaveric study to evaluate the efficacy of multiple fluoroscopic projections in detecting intra-articular penetration of the screws during femoral neck fracture fixation and also to determine the most suitable radiographic projection. Models of intra-articular penetration in 8 normal proximal femur specimens were created by placing the pins in different quadrants of the...