Internal fixation of fractures of both bones forearm: Comparison of locked compression and limited contact dynamic compression plate (Letter 1).

Sir,

We read with interest the article by Saikia et al. entitled, “Internal fixation of fractures of both bones forearm: Comparison of locked compression and limited contact dynamic compression plate.”1 We would like to discuss a few issues of this manuscript. The surface on which radius plating was done has not been mentioned explicitly.1 According to Anderson et al., volar surface radius plating for proximal fractures can lead to decreased pronation. They preferred dorsal plating for such fractures using Thompson's approach.2

The criteria for union of diaphyseal forearm fractures are ill-defined. On cross-referencing the parent paper cited in the current article,1 it is stated that it is very difficult to judge union roentgenographically2 as anatomic reductions make fracture line disappear after fixation. Using the functional score as a surrogate of union is misleading as it is based not only on union but also on the nature of fixation and the bone quality too. At times, commenting on union is easier in the presence of external callus. Hence, the “time to union” has an innate bias in it, especially in anatomically reduced fractures.

As per Field et al., the object radius of curvature is a major determining factor for interface contact area, than the plate design.3 In this concept, any limited contact plate will act like an ordinary DCP if the radius of curvature of bone is less than that of the plate, as more circumference of bone will be in contact with the plate undersurface between the undercuts. The locked compression plate (LCP) and limited contact dynamic compression plate (LC-DCP) are broader (width 11 mm) than a 3.5 DCP (width 10 mm).4 This further lessens the advantages of any limited contact device in bones with smaller radii of curvature like forearm bones. These devices will work better in broader bones like humerus. We had two cases of ulnar side implant prominence after using LC-DCP in <20-year-old patients.

Using a locking plate in compression mode increases the bone plate contact area. To combine the best features of limited contact and angle stability, recently a minimum contact LCP (MC-LCP) has been introduced which has proven better than an LC-DCP.4