Search results for "osteosynthesis"
showing 10 items of 46 documents
In Silico Finite Element Modeling of Stress Distribution in Osteosynthesis after Pertrochanteric Fractures
2022
A stabilization method of pertrochanteric femur fractures is a contentious issue. Here, we assess the feasibility of rapid in silico 2D finite element modeling (FEM) to predict the distribution of stresses arising during the two most often used stabilization methods: gamma nail fixation (GNF) and dynamic hip screw (DHS). The modeling was based on standard pre-surgery radiographs of hip joints of 15 patients with pertrochanteric fractures of type A1, A2, and A3 according to the AO/OTA classification. The FEM showed that the stresses were similar for both GNF and DHS, with the medians ranging between 53–60 MPa and consistently lower for A1 than A3 fractures. Stresses also appeared in the fixa…
Pathogenesis and clinical relevance of bone marrow embolism in medullary nailing — demonstrated by intraoperative echocardiography
1993
Abstract For the clarification of pulmonary impairment after medullary nailing of femoral fractures, the intramedullary pressure in the femoral cavity during the operative procedure was investigated. In addition, an intraoperative transoesophageal echocardiography was performed which revealed two phenomena occurring once the intramedullary pressure had increased: snow-flurry and configured emboli. An experimental study in sheep was performed in order to define the substrata of the sonographic echoes. The level of intrafemoral pressure which would result in bone marrow intravasation and the substrata of the echocardiographic echoes were studied in sheep by applying pressure to the femoral ca…
Screw fixation of radial head fractures: Compression screw versus lag screw—A biomechanical comparison
2009
Abstract Introduction Secondary loss of reduction and pseudarthrosis due to unstable fixation methods remain challenging problems of surgical stabilisation of radial head fractures. The purpose of our study was to determine whether the 3.0 mm Headless Compression Screw (HCS) provides superior stability to the standard 2.0 mm cortical screw (COS). Materials and methods Eight pairs of fresh frozen human cadaveric proximal radii were used for this paired comparison. A standardised Mason II-Fracture was created with a fragment size of 1/3 of the radial head's articular surface that was then stabilised either with two 3.0 mm HCS (Synthes) or two 2.0 mm COS (Synthes) according to a randomisation …
Minimally invasive plate fixation in femoral shaft fractures
1997
Bridge-plating with its advantages in terms of vascularity and bone healing is a well established procedure today in the treatment of comminuted femoral fractures. Bridge-plating means that the fracture site is not interfered with during the operative procedure. This paper introduces a surgical technique in which the plate is inserted through isolated proximal and distal incisions only, behind the vastus lateralis. Alignment is secured by the plates, the fracture site remains untouched, fixation and screw insertion is restricted to the proximal and distal main fragments. Longitudinal femoral fractures extending right into the trochanteric and or condylar areas are the main indication for mi…
A biomechanical evaluation of methods of distal humerus fracture fixation using locking compression plates versus conventional reconstruction plates.
2004
OBJECTIVES To examine the biomechanical behavior of 2 techniques of double-plate osteosynthesis for fractures of the adult distal humerus using conventional reconstruction plates and locking compression plates. DESIGN Basic science study. SETTING Experimental in vitro study. PATIENTS/PARTICIPANTS Forty fresh-frozen human distal humeri specimens. INTERVENTION Four matched groups with 10 humeri each, median age 74 years (46-95), were created using similar bone mineral density values. Two standard configurations of double-plate osteosynthesis (dorsal or 90 degrees configuration) with either conventional reconstruction plates or locking compression plates were studied for biomechanical properti…
Acetabulumfrakturen im Alter
2002
Acetabular fractures in elderly patients are rare injuries, but their incidence is increasing. Poor bone quality due to osteoporosis and an increased operative risk due to concomitant disease are factors complicating surgical therapy. Literature does not provide generally accepted treatment protocols. In a 4-year period, 27 patients who were 65 years or older and who had an acute displaced fracture of the acetabulum were admitted to our department. Four minimally displaced and stable fractures were managed conservatively. Internal fixation was performed in 16 cases. According to the Merle d'Aubigne score, in 15 out of 18 surviving patients excellent or good results were found. Treatment str…
Callus distraction of the femur and tibia. Experience with the Monofixator - indications for reosteosynthesis
1998
In a 4-year period, 18 patients underwent callus distraction of the femur or tibia with the use of a unilateral external fixator. Twelve patients had post-traumatic bone loss resulting from complex lower-limb fractures. The bony defect was located in the tibia in 11 cases and in the femur in one case. All patients had major associated soft-tissue lesions. The length of the bony defect averaged 6.25 cm. Eight fractures were infected at the beginning of treatment. Six other patients underwent callus distraction for reasons of limb shortening. Five femora and one tibia were lengthened. The average increase in length was 6.5 cm. There were no fixator-related complications during distraction. Th…
Ergebnisse nach primärer ungebohrter Tibianagelung von Unterschenkelfrakturen mit schwerem offenem oder geschlossenem Weichteilschaden
1996
Primary stabilization was performed in 72 tibial fractures with sever open (n = 37) or closed (n = 35) soft tissue injury using unreamed interlocking nails. In 60 (83%) cases the fractures healed without additional procedures. There were 2 cases of osteitis, but both these fractures healed after removal of the nail or after reamed nailing. In 9 patients with delayed union reamed nailing (n = 8) or bone grafting (n = 1) led to healing. In 1 patient with hypertrophic pseudarthrosis, union was achieved after substitution of a reamed nail for the anreamed nail. The infection rate was similar to that observed with external fixation. More secondary procedures, such as bone grafting or a change of…
Stability of radial head and neck fractures: a biomechanical study of six fixation constructs with consideration of three locking plates.
2007
Open reduction and internal fixation of radial neck fractures can lead to secondary loss of reduction and nonunion due to insufficient stability. Nevertheless, there are only a few biomechanical studies about the stability achieved by different osteosynthesis constructs.Forty-eight formalin-fixed, human proximal radii were divided into 6 groups according to their bone density (measured by dual-energy x-ray absorptiometry). A 2.7-mm gap osteotomy was performed to simulate an unstable radial neck fracture, which was fixed with 3 nonlocking implants: a 2.4-mm T plate, a 2.4-mm blade plate, and 2.0-mm crossed screws, and 3 locking plates: a 2.0-mm LCP T plate, a 2.0-mm 6x2 grid plate, and a 2.0…
Surgery for fracture of the calcaneus. 5 (2-8) year follow-up of 20 cases.
1993
20 displaced intraarticular fractures of the calcaneus were treated by open reduction and internal fixation. Results were evaluated according to a standardized protocol. With an average follow-up of 5 (2-8) years, results were excellent or good in 15 cases and fair or poor in 5 cases. An accurate radiographic study and CT scanning are essential for understanding these fractures. We feel that restoring calcaneal shape as anatomic as possible, getting an appropriate reduction of the posterior joint surface by a surgical procedure with early mobilization, and delayed weight bearing would be a good option in treatment of these fractures.