This experimental project was designed to evaluate the effect of various factors contributing to the success of autogenous bone and joint transplantation in animals. One hundred and twenty-one transplants were performed, using the metacarpophalangeal joint, in eighty-five dogs. The effect of the size and location of the transplant, duration of follow-up, and the age of the animal on the survival of the grafts was studied in sixty-six transplants in the forty-five dogs which were suitable for study.
Regardless of the final fate of the transplanted joints, most of the grafts healed well at the areas of bone contact when transplanted to toes, and the joint architecture remained relatively normal (roentgenographically) up to about fifteen weeks after transplantation.
After fifteen weeks, the following morphological changes appeared: narrowing of the joint spaces, widening of the bone ends, cartilaginous degeneration, fragmentation of adjacent bone, invasion of joint space by fibrous tissue, and complete destruction of the architecture of the joint in some of the transplants.
Transplants carried out in young puppies showed essentially the same findings except that in addition there was retardation of growth in the digit with the transplanted joint.
Joints transplanted to muscle without bone contact showed necrosis which was followed by cortical resorption with minimum osteoblastic activity; this was attributed to absence of function of these joints.
Clinical and roentgenographic observations were made of seven transplanted finger and toe joints in man. In this series there was no consistent correlation between the clinical results and the actual anatomical state of the joint.
The survival and function of a composite graft requires not only a restoration of tissue continuity but the maintenance of the correct relationship of the component parts.
The significance of such factors as the impaired blood supply, denervation, stresses of abnormal mechanics, and derangement of the architecture of the joint on the fate of the transplanted joints is discussed; further study is indicated.