Experimental studies on cellular mechanisms involved in healing of animal and human flexor tendon in synovial environment.

An experimental model is presented to study superficial healing of animal and human flexor tendon in a synovial environment. The results indicate that in a synovial environment a cut and resutured flexor tendon may heal in its superficial parts without adhesion formation. When cell seeding via the synovial fluid is prevented by a dialysing membrane the picture, as revealed by light microscopy, is little changed. When the model is modified so that the central cells of the tendon are exposed to the synovial fluid, these cells become activated. The results indicate that superficial as well as deep cells of the tendon possess a potential for repair if they are adequately nourished, and that cell seeding plays no major role in the process of proliferation and repair. The picture of intrinsic repair potential in a synovial environment seems to be valid also for human flexor tendons.