A method of treatment for proximal radio-ulnsar synostosis has been described. This method has been used in four patients in whom the conidition was of traumatic origin. Two case histories have been presented: one of a man in whom the proximal fragment of the radius was sufficiently long to receive the central rod of the swivel; and the other of a woman in whom a longer segment of the proximal end of the radius had previously been resected, with the result that one end of the central rod of the metal prosthesis had to be doweled obliquely into the proximal portion of the ulna.

We have not had the opportunity to use this method in cases of proximal radio-ulnar synostosis of congenital origin. However, we see no reason why it should not succeed equally well in these cases, for functional restoration is attained with greater ease in younger individuals; also in congenital radio-ulnar synostosis the proximal fragment of the radius is not shattered and has not been surgically tampered with. Against this advantage there is the fact that bones in young individuals sometimes produce excessive callus which may grow over and bridge the gap occupied by the metal prosthesis. Minimization of the surgical trauma and use of a comparatively longer metal cylinder to span the gap created by the resected portion of the radius may eliminate this hazard. Needless to say, in younger individuals the girth of the cylinder portion of the prosthesis should be the same as that of the resected bone and the width of the central rod should not be much larger than the medullary cavity of the radius.