The most important results of this investigation may be summarized as follows: Pott's disease in childhood is very well capable of healing under purely conservative measures. The average duration of the healing process in a sanatorium is at least four years. The Albee operation, when undertaken in an early stage, is unable to protect the vertebral column against deformity. With increasing destruction of the vertebrae, the tibial graft undergoes marked changes with circumscribed resorption, usually immediately over the gibbus. Being plastic bone tissue, it is bent out of shape. It, therefore, appears useless to undertake the operation upon children in the early stage. The facts that at this time it is impossible by the means of the roentgenograms to say anything definite regarding the extension of the vertebral tuberculosis, and that at the time of operation vertebrae which appear roentgenographically normal and which are not included in the region of fusion may be diseased, these facts, likewise, speak against operation in the early stage.

In the late cases in which the spondylitis is already on the way to healing or is already healed as a result of conservative measures, the problem is different. In such cases, the graft may contribute considerably to the stabilization of the defective spine, especially in the lumbar region, and to the assurance of maintaining the result already reached. Following the necrotic process, subluxations in the intervertebral joints certainly result from the dislocation of the body fragments. This, no doubt, leads to seriously altered statics in the whole vertebral column and to manifestations of insufficiency of the muscular and ligamentous apparatus with pain. We must admit, however, that the juvenile organism is able to adjust itself to even a very severe deformity over a very long period of time. Ultimately, however, increasing manifestations of fatigue appear. These are often interpreted as indications of recurrence of the tuberculous inflammation, whereas they are as a matter of fact merely signs of static insufficiency. In such cases, operation seems to be indicated. It is in these cases, however, merely symptomatic and not directed against the disease itself. Our material, although rather limited, seems to indicate that, even before the onset of static insufficiency of the spine, the spinal fusion may be effective immediately after the conclusion of conservative treatment. It is perhaps, as a new stimulus, capable of forcing the organism into the last stage of healing, which is usually somewhat protracted, and so of bringing about somewhat more rapidly bony union of the vertebral fragments. The observations of Waldenström and Johansson seem to point in this same direction.