A cartilagenous graft as an adjunct to finger joint implant arthroplasty.

A method is described which is proposed to prolong the functional life of a Silastic finger joint endoprosthesis which has been shown to fail because of abrasion and cutting by the recipient bones. Swanson design Silastic finger joint prostheses were implanted into the knee joints of rabbits. The technique of simultaneously transplanting ear cartilage to the prosthetic implant bed was tested for the purpose of protecting the prostheses from wear and eventual failure. The clinical, radiographic, gross, and histologic results of the animals implanted for 1, 3, and 6 months show that the cartilage graft remains viable and it proliferates. The cartilage provides a smooth, gliding surface with normal appearing joint fluid surrounding the Silastic implant. Control limbs, with no cartilage grafts, had thinner, fibrous tissue encapsulating the implants. The presence of the cartilage reduced the amount of prosthetic wear particles observed in the tissue sections, thus indicating a protective function. The rabbit model developed an osteoarthritis that was caused by the prostheses in its knee joints and was unaffected by our cartilage grafting procedure. The success of our cartilage grafts, in the presence of such an arthritis, provides the impetus for its clinical use in arthritic human finger joints. Further studies are necessary to determine the clinical feasibility of a cartilage grafting technique and its efficacy in reducing implant failure in human finger joints.