EXPERIMENTAL AND MORPHOLOGICAL ASPECTS OF FAILED TENDON AUTO- AND ALLOGRAFTS AFTER ACL RECONSTRUCTION IN EARLY POSTOPERATIVE PERIOD

Abstract

Purpose of the study – search for morphological cause of failure for free tendon auto and allografts after ACL reconstruction of the knee joint in early postoperative period during in vivo experiment. Materials and methods. Experiment included two groups of rabbits, each group consisting of 9 animals. In the first group the authors performed ACL autografting by semitendinous tendon harvested from operated limb. In the second group, ACL allografting was made by foot flexor tendon harvested earlier in rabbits excluded from present or other experiments after pretreatment and sterilization in modified Belyakov’s medium. Results. The major cause for failure of ACL tendon grafts after reconstruction in early postoperative period is the necrosis of intraarticular portion of auto or allograft on the 15th day after the procedure. In case of overexposure of the graft in early period the authors observed rupture along intraarticular portion or - more probable - along the demarcation area (serrated line) rather than graft slipping from bone tunnel with slackening. Intra-tunnel graft portion during first several days after the procedure became surrounded by granulated tissue in contrast to intraarticular portion that remained bare of such support. Conclusion. Comparative experimental and morphological study of two options of ACL reconstruction demonstrated a uniformity of alterations in dynamics with a certain delay in development of compensatory and adaptive processes after allografting. Necrosis (or homogenization) of intraarticular portion of auto or allograft is the cause for potential failure of ACL reconstruction in case of an extremely early and unjustified active rehabilitation.