Search results for "Fixation"

2016

Purpose The use of new headless compression screws (HCSs) for scaphoid fixation is growing, but the nonunion rate has remained constant. The aim of this study was to compare the stability of fixation resulting from four modern HCSs using a simulated fracture model to determine the optimal screw design(s). Methods We tested 40 fresh-frozen cadaver scaphoids treated with the Acumed Acutrak 2 mini (AA), the KLS Martin HBS2 midi (MH), the Stryker TwinFix (ST) and the Synthes HCS 3.0 with a long thread (SH). The bones with simulated fractures and implanted screws were loaded uniaxially into flexion for 2000 cycles with a constant bending moment of 800 Nmm. The angulation of the fracture fragment…

The experimental study of the hybrid fixation in ACL reconstruction

2012

Abstract The article is approaching an interesting topic regarding ACL reconstruction using the hamstring tendons (semitendinosus and gracilis) as the graft. The initial graft fixation after ACL reconstruction is mechanical and it must assure the stability of the system until the biologic integration takes place. No fixation system is as strong as the native ACL insertion. Therefore, hibrid fixation like an improvement of simple fixation is a field worth studying. The fixation shown in this article is the Hybrid fixation consisting of direct fixation with interference screw and an extra cortical fixation over a cortical screw.

Transsacral Bar Osteosynthesis

2017

Uni- or bilateral sacral ala fractures in elderly persons may cause significant disability and result in non-union, if treated non-surgically. Transsacral positioning bar osteosynthesis provides the advantages of a minimally invasive approach yet reducing the risk of implant loosening. A threaded 6 mm bar is inserted through the posterior part of the ilium and the SI-joint, and advanced through the center of the S1 vertebral body towards the opposite posterior ilium. Washers and nuts are placed and tightened on both ends of the bar providing moderate compression of the vertical fracture planes in the sacrum. The stability of fixation does not depend on the bone mineral density of the sacrum…

Sind winkelstabile Plattensysteme mit elastischen Eigenschaften für die Stabilisierung der Oberarmkopffraktur vorteilhaft? / Eine in-vitro biomechani…

2004

AbstractWinkelstabile Platten werden mit zunehmender Häufigkeit zur Stabilisierung von Oberarmkopfbrüchen verwendet. Rigide Implantate führen bei osteoporotischen Knochenverhältnissen u. U. aber häufiger zum Versagen. Um den Effekt der Implantatelastizität zu beurteilen wurden in einer in-vitro Studie die biomechanischen Eigenschaften eines rigiden und eines elastischen winkelstabilen Plattensystems vergleichend analysiert. An 8 Humeruspaaren wurde eine instabile subkapitale Fraktur simuliert. Die Proben wurden axial- und torsions-belastet. Analysiert wurden die Steifigkeit, das Setzverhalten unter Dauerlast und die Versagensbelastung.Das elastische Plattensystem kennzeichnete sich durch ei…

Dynamische Analyse von Osteosynthesen am Olecranon: ein in-vitro Vergleich zweier Osteosynthesesysteme / Dynamic analysis of olecranon osteosyntheses…

2008

INTRODUCTION The aim of the present study was to develop a test setup with continuous angle alteration to imitate elbow joint motion for the mechanical evaluation of tension band wiring and a newly designed intramedullary nail. MATERIALS AND METHODS The servo-pneumatical test stand worked with a rotational angle-adjusted and a linear force-adjusted engine. The fracture model was dynamically tested under cyclic loading imitating elbow joint motion. In total, 14 fresh cadaver upper extremities underwent olecranon fracture by means of transverse osteotomy and were assigned to two groups: tension band wiring and intramedullary nailing. There was a continuous angle alteration between 0 and 1000 …

In-vitro fatigue and fracture performance of three different ferrulized implant connections used in fixed prosthesis

2021

Background/purpose: The aim of the present in vitro study was to evaluate fatigue resistance of dental fixtures in three different types of fixture/abutment finishing line. Materials and methods: Transmucosal dental implants, with or without ferrulized neck, underwent fatigue tests (static and dynamic load) using the following standard protocol: UNI EN ISO 14801:2016. Two types of loading devices (screw- or cement-retained restoration) were also tested, and fatigue cycle tests were run to failure. Data of static and dynamic load tests were analyzed by proper statistical methods. Results: Following standard protocol for fatigue testing, the ILC type (Implant Level with ferrulized neck and ce…

Etiology, Modalities of Zygomaticomaxillary Complex Fracture, open reduction and fixation.

2020

Background Zygomatic complex fracture is second most common mid face fracture and frequent amongst the maxillofacial trauma. Fracture pattern ranges from simple to comminuted and from minimally displaced to severely displaced depending on various factors. Material and methods 98 patients with zygomaticomaxillary complex fracture reporting during December 2017 to January 2020 were included in the study. On the basis of radiographic evaluation and computerized tomography scan (CT scan) with 3D reconstruction severity of fracture was assessed and different treatment options were selected. Results Road traffic accident accounted as the leading cause of fracture (57.1%) followed by self-fall (16…

Osteosynthese am proximalen Humerus mittels winkelstabiler Platte oder Doppelplatte: eine vergleichende biomechanische Untersuchung / Angle-fixed pla…

2008

Internal fixation of fractures of the proximal humerus needs a high stability of fixation to avoid secondary loss of fixation. This is especially important in osteoporotic bone. In an experimental study, the biomechanical properties of the angle-fixed Philos plate (internal fixator) and a double-plate osteosynthesis using two one-third tubular plates were assessed. The fracture model was an unstable three-part fracture (AO type B2). Eight pairs of human cadaveric humeri were submitted to axial load and torque. In the first part of the study, it was assessed to which degree the original stiffness of the humeri could be restored after the osteotomy by the osteosynthesis procedure. Subsequentl…

Reimplantation: clinical Implications and outcome of dry storage of avulsed teeth

2010

Reimplantation refers to the insertion and temporary fixation of completely or partially avulsed teeth that have resulted from traumatic injury. Reimplantation of an avulsed tooth depends on certain clinical conditions like phy- siological status of periodontal ligament (PDL), the stage of root development and the length of extra oral time. Depending on the patient’s age, retention of the permanent incisor can maintain the aesthetic appearance, occlusal function and alveolar ridge height. Though the risk of progressive replacement resorption and subsequent tooth loss is high after a long dry storage, reimplantation makes a provision for an aesthetically acceptable permanent prosthesis at a …

Photoelastic analysis of conventional and locking system for treatment of mandibular angle fractures with a single plate

2021

Made available in DSpace on 2021-06-25T10:28:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-04-01 Background: This photoelastic analysis evaluated stress distribution in different osteosynthesis systems, conventional and locking, used for treatment of mandibular angle fractures with a single plate. Material and Methods: Angle fractures were simulated in mandibles made of photoelastic resin. Following Champy’s method, plate osteosynthesis was performed. The samples were divided into five groups: Group 1, non-fractured mandible; Group 2, two screws were installed in each segment using a conventional system; Group 3, two screws were installed in each segment using a locking system; …