Synovium as a nutritional medium in tendon grafting.

The mechanism of tendon healing and the role played by the synovial sheath are still obscure and controversial. In the present experimental study free tendon grafts were nourished by synovial fluid only. By morphological and cytochemical techniques viable cells were found in the superficial zones of the tendon, capable of both proliferation and production and production of new collagen. This repair process affected predominantly the ends of the grafts. At the centre of the specimens degenerative changes appeared to an increasing extent throughout the observation period of 12 weeks. Adhesions to the surrounding tissues did not form. It is concluded that fibroblasts, most probably originated from the superficial cell layers of the tendon are capable of regeneration and synthesis of new collagen and that synovial fluid plays an important role in the metabolic exchange of the superficial scantily vascularized areas of the tendon. The observations are discussed in relation to the present concepts of tendon surgery.