Application of Tissue Engineering Techniques for Rotator Cuff Regeneration Using a Chitosan-Based Hyaluronan Hybrid Fiber Scaffold

Abstract

Background The current surgical procedures for irreparable rotator cuff tears have considerable limitations. Tissue engineering techniques using novel scaffold materials offer potential alternatives for managing these conditions. Hypothesis A chitosan-based hyaluronan hybrid scaffold could enhance type I collagen products with seeded fibroblasts and thereby increase the mechanical strength of regenerated tendon in vivo. Study Design Controlled laboratory study. Methods The scaffolds were created from chitosan-based hyaluronan hybrid polymer fibers. Forty-eight rabbit infraspinatus tendons and their humeral insertions were removed to create defects. Each defect was covered with a fibroblast-seeded scaffold (n = 16) or a non-fibroblast-seeded scaffold (n = 16). In the other 16 shoulders, the rotator cuff defect was left free as the control. At 4 and 12 weeks after surgery, the engineered tendons were assessed by histological, immunohistochemical (n = 2), and biomechanical (n = 6) analyses. Results Type I collagen was only seen in the fibroblast-seeded scaffold and increased in the regenerated tissue. The tensile strength and tangent modulus in the fibroblast-seeded scaffold were significantly improved from 4 to 12 weeks postoperatively. The fibroblast-seeded scaffold had a significantly greater tangent modulus than did the non-fibroblast-seeded scaffold and the control at 12 weeks. Conclusion This scaffold material enhanced the production of type I collagen and led to improved mechanical strength in the regenerated tissues of the rotator cuff in vivo. Clinical Relevance Rotator cuff regeneration is feasible using this tissue engineering technique.