Received Jan 20; Accepted Jul This article has been cited by other articles in PMC. Abstract The objective of this article is to systematically review the currently available literature to formulate evidence-based guidelines for the treatment of femoral shaft nonunions for clinical practice and to establish recommendations for future research. The search was restricted to articles from January to March written in the English, German, or Dutch languages.
The output depends on the polarization of the input. Suppose polarization axes x and y parallel with the fast and slow axis of the waveplate: The polarization of the incoming photon or beam can be resolved as two polarizations on the x and y axis.
If the input polarization is parallel to the fast or slow axis, then there is no polarization of the other axis, so the output polarization is the same as the input only the phase more or less delayed.
Wave-plate osteosynthesis not the amplitude but both sine values are displayed, then x and y combined will describe a circle. Full-wave, or sensitive-tint plate[ edit ] A full-wave plate introduces a phase difference of exactly one wavelength between the two polarization directions, for one wavelength of light.
If a linear polarizer oriented perpendicular to the original polarization is added, this green wavelength is fully extinguished but elements of the other colors remain. This means that under these conditions the plate will appear an intense shade of red-violet, sometimes known as "sensitive tint".
These plates are widely used in mineralogy to aid in identification of minerals in thin sections of rocks. Addition of plates between the polarizers of a petrographic microscope makes easier the optical identification of minerals in thin sections of rocks in particular by allowing deduction of the shape and orientation of the optical indicatrices within the visible crystal sections.
In practical terms, the plate is inserted between the perpendicular polarizers at an angle of 45 degrees.
This allows two different procedures to be carried out to investigate the mineral under the crosshairs of the microscope. More simply, in ordinary cross polarized light, the plate can be used to distinguish the orientation of the optical indicatrix relative to crystal elongation — that is, whether the mineral is "length slow" or "length fast" — based on whether the visible interference colors increase or decrease by one order when the plate is added.
A slightly more complex procedure allows for a tint plate to be used in conjunction with interference figure techniques to allow measurement of the optic angle of the mineral. The optic angle often notated as "2V" can both be diagnostic of mineral type, as well as in some cases revealing information about the variation of chemical composition within a single mineral type.The wave plate was chosen for the treatment of non union femoral diaphyseal fractures, due to the use of a DCP plate initially, which should be removed, even though it was already causing an injury of the periosteal flow due to bone contact beneath the plate.
When the medial buttress due to a bony defect is missing, the laterally applied plate is subjected to cyclic bending and will undergo fatigue fracture. This dilemma is compensated by a wave plate with bone graft: the compression forces are redirected to the lateral cortex, and the plate is again subjected to tension.
We have treated 42 consecutive complex ununited fractures of the femoral shaft by wave-plate osteosynthesis at five different medical centres.
In conventional plate osteosynthesis, anatomic reduction is sought because it increases stability, whereas in locking plate osteosynthesis the quality of the reduction is less vital, provided that the local soft tissues (and therefore vascularization of the fragments) are maintained intact.
L’osteosintesi con placca e vite è una tecnica conosciuta e utilizzata dai chirurghi da decine d’anni. Negli anni ’60, Muller e Allgöwer stabilirono le regole di base dell’osteosintesi con placca e ne definirono con molta precisione le modalità operatorie. Between and , we treated operatively 28 patients with a symptomatic mid-shaft clavicular non-union using AO osteosynthesis, including bone grafting.
Nine patients had a wave-plate osteosynthesis and 19 a standard AO/ASIF osteosynthesis.