Piezoelectric Injectable Anti-Adhesive Hydrogel to Promote Endogenous Healing of Tendon Injuries.

Achilles tendon rupture has become a common sports injury nowadays, but tendon repair is still is a challenge in the clinical practice. Tendon adhesion, which results from exogenous healing, is a crucial problem impairing tendon repair. Meanwhile, insufficient endogenous healing from the tendon stem cells, makes tendon repair even more difficult. Here, a piezoelectric injectable anti-adhesive hydrogel (PE-IAH) is reported, which can simutaneously promote endogenous healing while inhibiting exogenous healing in the tendon repair process. The in vivo study reveals that the PE-IAH can form a physical barrier in situ at the tendon injury site, which reduces the inflammatory response and effectively prevents the tendon from adhering to surrounding tissue. Meanwhile, the piezoelectric short fibers incorporated in the hydrogel can evidently promotes the proliferation and differentiation of tendon stem cells due to piezoelectric effect under ultrasound excitation. Altogethter, the PE-IAH successfully accelerates the endogenous healing of tendon in addition to the anti-adhesion purpose, resulting in remarkably elevated tendon functions (Achilles Functional Index: -15.6 of PE-IAH versus -30.6 of injectable anti-adhesive hydrogel (IAH), Day 14). This study provides a new strategy for advanced healing and functional recovery of Achilles tendon, which is promising to become a potential clinical treatment option.