Purpose of the study: The aim of this work was to assess results after treatment by nailing of nonunion of the humeral shaft. In particular, we focused on consolidation and factors predictive of failure.

Material and method: A prospective study was conducted in 13 consecutive patients presenting aseptic nonunion of the humeral diaphysis. There were five cases after orthopedic treatment and eight cases after internal fixation. Two patients had iterative nonunions. Locked nailing was performed with three successive types of nails: the Seidel nail in four cases, the Russel Taylor nail in seven, and the ACE nail in two. Anterograde nailing was used for the first three cases and retrograde nailing for the others. All patients were followed regularly in our department. Last follow-up was one to seven years after nailing.

Results: Five nonunions (38%) did not consolidate after locked nailing. Consolidation was achieved in the other patients after four to 18 months. The anatomic result was good in these patients. Between the success and failure groups, there was no significant difference in age, gender, type of fracture, first intention treatment, delay from fracture to nailing, type or diameter of the nail, surgical access or not to the fracture site during nailing, or duration of complementary fixation. Anterograde nail insertion, used in our first three patients in this series, appeared to affect shoulder function. The retrograde route was used in other patients and did not appear to have any impact on the elbow itself or the elbow region.

Discussion: This clinical study was unable to identify clinical factors explaining failures but did provide several arguments suggesting that defective primary stability of the initial fixation could be incriminated in the failures.

Conclusion: Centromedullary locked nailing is a simple technique with potential for resolving difficult problems of nonunion. Good functional outcome can be obtained when consolidation is achieved. Rather than abandoning this technique, it would be advisable to conduct further research to determine what factors are determinant in its failures.