The healing process of transplanted digital tendon sheath synovium. Experimental autoradiographic studies in chickens.

The present investigation is a sequel to a previous report on the composition and fate of the pseudo-sheath formed by secondary healing, and of free tendon sheath autografts covering defects in the digital tendon sheaths of chickens (Eiken & Rank, 1977). Autoradiography was used to determine graft survival and cell regeneration. The distribution of labelled cells indicated that the granulation tissue of secondary healed defects formed around implanted Silastic rods consists of fibrous scar tissue. The tendon sheath autografts, on the other hand, were found to survive, demonstrating a well-preserved synovial surface. These findings probably imply new concepts of tendon surgery. The Silastic rod induced some foreign body reaction in the healing synovium. It is assumed that this reaction is reversible, but this could not be established in the present investigation. Further study is being made of this problem.