Two decades of using metallic fixation in fractures of the femoral neck have produced thousands of cases, and the reported results show 80% to 90% union. However, certain of these fractures did not lend themselves easily to reduction or nailing and required secondary surgery to achieve this incidence of healing.
Often this situation manifests itself early in the postoperative period by a complete dissociation of the fragments, which is easy to recognize clinically and confirm by roentgenograms which show that the reduction or nailing is inadequate. When this occurs, secondary surgical procedures often are successful in achieving union with little or no increase in the period of disability. Unfortunately, this is not always the case, and incipient nonunion is often not evident until many months after the injury.
If the nail has remained in place and the fragments have not changed position after surgery, clinical examination is rarely helpful in
ROSENBERG N, REICH R, KROHN M. Prognosis and Early Diagnosis of Nonunion of Femoral Neck Fractures by Laminography. AMA Arch Surg. 1956;73(1):157-163. doi:10.1001/archsurg.1956.01280010159021