Introduction: Anterior spinal instrumentation of the thoracic and lumbar spine has gained in popularity since Dwyer et al [1] developed the cable system in 1964. However, implant loosening, screw breakage and cut-throughs have been noted clinically when using Dwyer or Zielke's Ventrale Derotations Spondylodese (VDS) instrumentations [2,3]. To avoid these complications and pseudarthrosis, one ma...

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...

According to the problem of screw fracture of electric submersible pump unit in Shengtuo oilfield, the reasons for the screw fracture are analyzed from three aspects: material, strength and pretightening force. The preliminary result shows that the imbalanced pretightening force of screw is the main reason of screw fracture. By means of Ansys software, the static and modal analyses for the elec...

The aim is to present our new method of compression, a compression tube instead of conventional compression screw and to investigate the difference of proximal locking screw bending resistance between compression screw application (6 mm wide contact) and compression tube (two contact points with 13 mm gap) application. We formed six groups each consisting of 10 proximal locking screws. On metal...

This report describes an eddy current system for locating distal transverse screw holes of an intramedullary nail. In fracture surgery, screw holes on an intramedullary nail are in invisible situation. Although conventional X-ray methods can visualize screw holes in bone, they pose a danger due to X-ray exposure. Therefore, a system to find screw holes without X-ray exposure is required. We sol...

A preliminary study of acoustic emission during orthopaedic screw fixation was performed using polyurethane foam as the bone-simulating material. Three sets of screws, a dynamic hip screw, a small fragment screw and a large fragment screw, were investigated, monitoring acoustic-emission activity during the screw tightening. In some specimens, screws were deliberately overtightened in order to i...

this study was conducted to evaluate different nutrient solutions effects on agria potato mini-tubers production under aeroponic system. the experiment was conducted in the laboratory and greenhouse of ardabil sabalan behparvar company in 2013. four recommended nutrient solutions including: lommen and struik (1992), kang and han (2005), otazu (2010) and hoagland and arnon (1950) were used in a ...

BACKGROUND Tibial fixation of hamstring tendon grafts has been the weak link in anterior cruciate ligament reconstruction. HYPOTHESIS Use of a central four-quadrant sleeve and screw provides superior fixation when compared with standard interference screw fixation. STUDY DESIGN Controlled laboratory study. METHODS In eight pairs of cadaveric knees each anterior cruciate ligament was recon...

Objective Among the various sacropelvic fixation methods, S2 alar-iliac (S2AI) screw fixation has several advantages compared to conventional iliac wing screw. However, the placement of S2AI screw still remains a challenge. The purpose of this study was to describe a novel technique of free hand S2AI screw insertion using a K-wire and cannulated screw, and to evaluate the accuracy of the techni...