Fresh amniotic membraneversus acellular amniotic membrane for repair of the tendon sheath and prevention of tendon adhesion / 中国组织工程研究

ABSTRACT

BACKGROUND: Amniotic membrane has a unique structure that can block the penetration of certain substances, to ensure normal nutrition supply for the surrounded tissues, and is also characterized by anti-adhesion, good tissue compatibility, mild inflammatory reaction, few fibers and biodegradability. OBJECTIVE: To compare the effects of fresh amniotic membrane and acellular amniotic membrane to prevent adhesion and promote tendon healing during the repair of tendon sheath defects. METHODS: Sixty healthy male leghorn chickens were selected, and the model of tendon injury and tendon sheath defects was established at the third toes. The animal models were then randomly divided into three groups and underwent repair with fresh amniotic membrane (group A), acellular amniotic membrane (group B), and no treatment in control group (group C), respectively. Histological observation and biomechanical analysis of the third toes were performed after repair. RESULTS AND CONCLUSION: (1) Histological observation. Congestive edema and inflammatory response were found in all animals at 2 weeks after repair, but mildest in the group A and severest in the group C. These inflammatory responses gradually alleviated over time in the three groups. At 12 weeks after repair, the new tendon sheath formed in all the animals, which was more mature than that at 4 weeks after repair. The synovial cells on the surface of the tendon sheath were arrayed tidily with dense structure in the groups A and B, but in the group C, the synovial cells were distributed disorderly with loose structure and prominent fibrous tissues. (2) Biomechanical analysis. Tendon sliding distance in the groups A and B was significantly larger than that in the group C at 4, 8, 12 weeks after repair (P < 0.05), but there were no significant difference in the distance between the groups A and B (P > 0.05). At 4 and 8 weeks after repair, the maximum tensile strength was largest in the group A, sequentially followed by group B and group C (P < 0.05), but there were no significant difference among the three groups at 12 weeks after repair (P > 0.05). To conclude, both fresh amniotic membrane and acellular amniotic membrane can promote tendon healing and prevent the adhesion of tendon through tendon sheath reconstruction, but the fresh amniotic membrane is preferred to promote early tendon healing compared with acellular amniotic membrane.