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 25-28 September, 2018 | Singapore
Implants can contribute to the reduction as well as stabilization of a fracture.
An example of this is reduction obtained with a Steinmann pin used as a fracture distractor. This simple method can be applied to fractures of the humerus, femur and tibia. The pin diameter should be about 50% of the medullary canal and is inserted in a normograde manner. As the nail crosses the fracture line and is driven into the distal fragment reduction must occur. Cutting the tip of the pin before its insertion into the distal fragment limit penetration of the pin in the metaphyseal bone.
Reduction is facilitated by the use of bone clamps and by gentle hammering of the pin further distally avoiding rotational action. In a reconstructable fracture, once a satisfactory reduction has been achieved, is possible to secure it with bone clamps, cerclage wire or lag screws and gently withdrawn the pin before plate application. In comminuted fractures where the bone column is
not reconstructable, the pin is let in place after optimal alignment and length are achieved and a plate is applied in a splinting fashion.
Application of a plate on a straight portion of the diaphysis help restoring alignment while the plate acts as a splint maintaining reduction before definitive fixation.
In a short oblique diaphyseal fracture, is possible to obtain reduction with the aid of a plate in the following manner. The plate is secured on one main fragment
and an independent screw is inserted on the opposite fragment. By pushing and pulling with a laminar spreader placed between the end of the plate and the screw and with reduction forceps is possible to distract and reduce the fracture. Fig 5
FIG 5
For ileal body fractures distal radius and tibia fractures, a plate can be precisely contoured and secured with screws on one bone segment, a bone clamp placed between the plate and the second bone segment allow gradual reduction of the fracture. When the fracture is reduced the bone clamp is tightened and the plate is fastened with screws.
To correct small displacement and angulation of an oblique metaphyseal fracture, is possible to use a properly contoured plate in an anti-glide function. The plate is applied to one fragment and tightening the screws forces the opposite fragment to glide down the oblique fracture plane, obtaining reduction and maintaining stability at the same time.
Joystick Reduction
It is a very simple technique that allows reduction of small fragments in metaphyseal or articular fractures. Insertion of small threaded K. wires allows manipulation of the bone fragments with or without direct view.
Instrumental reduction has its advantages but come to a price to the fracture biology. The surgeon should keep in mind that “The repeated use of bone clamps and other reduction tools or implants may completely devitalize the fragments in the comminuted area, which may
have disastrous consequences for the healing process, including delayed union, non-union, infection or implant failure.”
Fracture Distractor
The fracture distractor (Synthes, Ltd., Paoli, Pa, USA; Jorgensen Laboratories, Loveland, Colo) is an instrument that allows distraction of the fracture by means of two pins inserted throw both cortices in the proximal and distal metaphysis of the fractured bone. After insertion, the fixation pins are attached to the distractor with finger nuts. The distraction is applied by turning the wing
nuts on the connecting threaded rod. As there is an inherent tendency of curved bones to straighten during distraction, angular and rotational corrections are usually necessary before definitive fixation. The mechanical advantage of the distractor allows easy distraction of the fragments but when is under load alignment corrections can be difficult. The fracture distractor can be used either in open reduction and closed/indirect reduction.
INDIRECT REDUCTION
Increased understanding of fracture healing, brought the concept of “biological internal fixation: that represents one of the major conceptual changes of the last decade.
The principle consists of minimizing the biological damage from the surgical approach and the implant contact. This principle is achieved at expenses of
less precise reduction and less rigid fixation. The
method of absolute stability by compression fixation is supplemented by the method of relative stability by splint fixation that results in a flexible fixation that stimulates callus formation.
The biological internal fixation come together with the technique of indirect reduction that greatly reduce the surgical trauma and help to keep bone fragments vital.
In indirect reduction the fracture lines are not directly
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43RD WORLD SMALL ANIMAL VETERINARY ASSOCIATION CONGRESS AND 9TH FASAVA CONGRESS








































































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