Biomechanical enhancement in rotator cuff repairs: the impact of innovative nanofiber technology.

Background: Rotator cuff repair surgeries often face high failure rates, particularly in cases involving tendon degeneration. Traditional repair techniques and devices frequently fail to adequately restore a healthy native enthesis and strong tendon-bone integration. This study investigates the efficacy of a novel, fully synthetic, bioresorbable nanofiber scaffold in restoring the native enthesis and enhancing the biomechanical properties and overall success of rotator cuff repairs, particularly in the context of chronically degenerated tendons. Methods: This study used an ovine model to simulate chronic tendon degeneration with subsequent rotator cuff transection and repair. All repairs were performed using the standard double-row configuration with suture tape; half of the repairs were augmented with the bioresorbable nanofiber scaffold. Nondestructive biomechanical testing was conducted to assess the strength of the repair constructs, followed by histological analysis of all tendon samples to evaluate tissue regeneration and integration at the repair site. Results: Results demonstrated that the scaffold group achieved significantly improved biomechanical properties (peak force, peak stress, equilibrium force, and equilibrium stress) compared to the suture only group, indicating enhanced repair strength and native enthesis restoration. Scaffold samples exhibited significantly decreased cross-sectional areas (ie, less fibrosis) which were similar to healthy tendons. Histological findings indicated the scaffold did not impede re-establishment of Sharpey-like fibers at the tendon insertion. Conclusion: This study provides compelling evidence that the use of a fully synthetic, bioresorbable nanofiber scaffold in rotator cuff repair significantly improves biomechanical outcomes and enthesis regeneration. These improvements were achieved while retaining close to native tendon thickness. The findings suggest that this scaffold represents a significant advancement in rotator cuff repair technology, offering a promising solution to enhance repair strength and quality of bone-tendon integration, especially in challenging cases of tendon degeneration.