1. A tubereculous hip rarely becomes fused of its own accord. The two cases of sponfaneous fusicon reported in this study had probably been transformed from an originally tuberculous infection to that of a Predominantly pyogenic infection through long years of secondary invasion and repeated surgical drainages.

2. From the results of this study, it appears that there is added proof that early fusion in young children is amply justified. Conservative measures, aimed at building up the general health and causing the subsiding of acute symptoms, during the initial period of three to six months are necessary for a smooth postoperative course. In view of the present-day antibiotic therapy, even this short period of conservative treatment may be safely curtailed in some cases. In this way, the long recumency in some forms of immobilization, and the distressing deformities, which usually follow long years of destruetion from lack of internal fixation, may be avoided.

3. The average time for roentgenographic evidence to fusion to appear after arthrodesis in a hip in this series was fifteen months in children and twelve months in adults. Real anatomical fusion with transarticular trabeculae may take an additional one or more years. In the light if the present study, it seems advisable that no secondary fusion operations be undertaked before fifteenth month in children or before the twelfth month in adults: that the average immobilization period be from twelve to eighteen months in children and from ten to twelve months in adults; and that the time for beginning ambulation be no sooner than the sixth month following arthrodesis in any case.