The authors have reviewed 45 cases of femoral neck fractures from January 1991 to September 1994 with special reference to fracture classification. Follow-up periods for these cases were more than 1 year for all of these cases. The results were as follows:

1. AO classification of femoral neck fractures is better than Garden's classification in its simplicity and less inter-observer variations.

2. AO classification of femoral neck fractures is better than Garden's classification in predicting healing complications of internal fixation of femoral neck fractures.

3. Another factors predicting healing complications are the accuracy of reduction and the postoperative bone scintigraphy.

With the above results, we concluded that AO classification of femoral neck fractures seems to be useful in clinical application to femoral neck fractures together with Garden's classification.