From the study of this group of patients, the following conclusions seem to be justified:
1. There is a type of arthritis which is peculiar to persons who have psoriasis and which has a predilection for the distal joints of hands and feet. The clinical and roentgenographic findings are characteristic and quite different from those of rheumatoid arthritis.
2. The pathological changes in this type of arthritis are constant, but are not sufficiently specific so that the diagnosis can be made with certainty from the microscopic section alone.
3. Both arthritic and skin manifestations respond to ACTH and cortisone, but the former responds to significantly lower doses. Improvement with hormone therapy is not permanent.
4. The disabling deformities of the toes can be greatly relieved by radical surgery.