A RETROSPECTIVE ANALYSIS OF PLATE CONTOURING IN THE TIBIA USING THE CONVENTIONAL 4.5 (NARROW) DYNAMIC COMPRESSION PLATE

Plate contouring is an essential part of plate osteosynthesis. Its saf ety and technical ease is dependent on plate factors (material and des ign) and the complexity of the contouring. Our purpose was to determin e the range of plate contouring; estimate the strain on the plate from the radius of curvature in the area of contouring; and determine whet her shaped plates had a reduction in their load carrying capacity. A r etrospective analysis of 500 radiographed tibias that had undergone os teosynthesis with the conventional dynamic compression plate was condu cted to evaluate the radius of curvature and degree of bend in the pla tes, and to determine whether plates were bent at screw holes. Contour ing of the plate to fit the bone was done by the surgeon at the time o f application. Postoperative radiographs were evaluated. We found that (a) the shorter the length of plate contoured, the greater the strain ; (b) plates were bent at screw holes, and these tended to be the area s of highest strain; (c) the range of plate strain was 0.6-16% (averag e 1.6%); and (d) plates were bent from 10 to 90-degrees (average 20-de grees).