Technical factors related to Herbert screw fixation

We reviewed 24 patients treated for an acute fracture or a nonunion of the scaphoid bone using the Herbert screw. Mean follow-up in 22 patients who returned for examination was 17 months. The overall union rate was 67% for both acute fractures and nonunions. Fracture healing correlated strongly with technical factors of the procedure. The fracture failed to heal in seven of nine cases with poor scaphoid realignment, inaccurate jig placement, or improper screw length for a nonunion rate of 78%. Conversely, without these technical problems, 14 (93%) of 16 fractures achieved union. Applying Herbert's criteria, a satisfactory rating for clinical function was achieved in 59% of all patients and for patient satisfaction in 68% of all patients. Although the postoperative immobilization period was reduced using the screw, the final functional result in our nonunions was similar to that reported for the Russe bone grafting procedure. Appropriate modifications of the standard technique and recognition of equipment limitations may improve union rates.