Scaphoid nonunion: role of anterior interpositional bone grafts.

Twenty-one cases of unstable fractures of the scaphoid were treated by open reduction, length restoration by interpositional anterior wedge grafting, and fixation with a Herbert screw to obtain union and restore carpal stability. There was primary union in 15 (71%) of 21 patients. Two failed cases were treated with a second anterior wedge graft and Herbert screw fixation; overall rate of union was 81%. Nonunions were related to improper screw placement, failure of compression at the nonunion, bone-graft resorption, or persistent avascular necrosis. In the united scaphoids, carpal instability was corrected, with improvement in the scapholunate angle (65 degrees to 54 degrees) and capitolunate angulations (35 degrees to 15 degrees). Scaphoid malalignment associated with nonunion was improved on biplanar tomographic measurement of the scaphoid angles.