Two modifications for insertion of the Herbert screw in the fractured scaphoid

Abstract

Since its introduction in 1984, the Herbert screw system has been used increasingly for fracture fixation and reconstruction of the scaphoid. The differential pitch of the double-threaded screw is designed to fix and compress the fracture fragments such that external immobilization is not necessary. The thread design al­ lows the trailing threads to be countersunk so that the screw does not impinge on articular surfaces and thus does not have to be removed. As experience with the fixation system has devel­ oped, several technical difficulties have become appar­ ent. A common difficulty involves excessive palmar placement of the screw with resultant inadequate frac ­ ture fixation (Fig. 1). A second common difficulty is accurately determining the prospective course of the screw after jig placement. Two modifications of the insertion technique are pre­ sented to help eliminate these difficulties. The first in­ volves creation of a trough in the palmar aspect of the trapezium to allow adequate dorsal jig placement. The second is a Kirschner (K) wire insert sleeve designed for the jig, which simplifies wire placement, allowing accurate radiologic determination of the eventual course of the screw. Technique