BACKGROUND Screw fixation of pelvic ring fractures is a common, but demanding procedure and navigation techniques were introduced to increase the precision of screw placement. The purpose of this case series was the evaluation of screw misplacement rate and functional outcome of percutaneous screw fixation of pelvic ring disruptions using a 2D navigation system. METHODS Between August 2004 an...

The intention of this study was to compare the biomechanical characteristics using 5 internal fixation methods used clinically to stabilize a pubic symphysis diastasis (PSD, Tile type B1).A 3-dimensional finite element model of PSD was simulated using 5 implants, including single superior plate (Single-Plate), superior and anterior plate (Dual-Plate), single cannulated screw (Single-Screw), cro...

A three-dimensional simulation of trabecular surface remodeling was performed to investigate the basic effects of a fixation screw on the trabecular structural changes in a vertebral body. Voxel-based finite elements were used to construct computational models of the bone and screw for an entire vertebral body with the screw and for the bone-screw interface. The remodeling simulation for the en...

STUDY DESIGN Evaluation using 3-dimensional screw trajectory software and computed tomographic scans. OBJECTIVE To investigate the anatomic feasibility of laminar screw placement in the upper thoracic spine compared with pedicle screw placement. SUMMARY OF BACKGROUND DATA Although laminar screws have been suggested as an alternative to pedicle screws in the upper thoracic spine, previous an...

We report a case of fixation of a scaphoid fracture using an Acutrak(®) screw. This screw is cannulated and headless, which allows it to be implanted below the surface of the bone. It uses the same concept of variable thread pitch as the Herbert screw, but unlike the Herbert screw, is fully threaded, with continuously varying pitch along its length. This variable pitch creates constant compress...

AIM In unique clinical situations where C1-C2 posterior fixation is not available or has previously failed, an anterior transarticular screw (ATAS) may be a viable alternative. However, there are no previous reports that investigate possible screw angles, screw entry points, and screw length based on computed tomography (CT) multiplanar reconstruction images in Turkish patients. The aim of this...

A 27-year-old woman with a type II odontoid fracture was treated by anterior odontoid screw fixation. Radiographic union at the fracture site was obtained 3 months after surgery. Nearly 3 years after surgery, she presented at a local Ear, Nose, and Throat (ENT) clinic with a 2-month history of dysphagia. Laryngoscopy identified the head of the odontoid lag screw. Plain radiography showed that t...