The Fractured Scaphoid

Abstract

Mechanical and vascular factors are involved in fractures of the scaphoid. It is the most mobile bone in the wrist, so that a fracture in it produces significant changes in the mechanics of the wrist joint. Under normal conditions angulation between the carpal bones follows the line from (A) to (B) (Fig. 182), but in fractures of the scaphoid the line runs from (A) to (C). In ulnar deviation, the fracture gap is widened and the distal fragment displaced radially (Fig. 183). A secondary movement of the intact scaphoid is that of palmar tilting during radial deviation, which produces a very typical displacement in the fractured bone (Fig. 184). Furthermore, palmar or dorsiflexion as well as all combined movements in the wrist and even finger movements are transmitted to the fracture.