Biological augmentation of rotator cuff repair using bFGF-loaded electrospun poly(lactide-co-glycolide) fbrous membranes

Abstract

Clinically, rotator cuff tear (RCT) is among the most common shoulder pathologies. Despite signifcant advances in surgical techniques, the re-tear rate after rotator cuff (RC) repair remains high. Insuffcient healing capacity is likely the main factor for reconstruction failure. This study reports on a basic fbroblast growth factor (bFGF)-loaded electrospun poly(lactide-co-glycolide) (PLGA) fbrous membrane for repairing RCT. Implantable biodegradable bFGF-PLGA fbrous membranes were successfully fabricated using emulsion electrospinning technology and then characterized and evaluated with in vitro and in vivo cell proliferation assays and repairs of rat chronic RCTs. Emulsion electrospinning fabricated ultrafne fbers with a core-sheath structure which secured the bioactivity of bFGF in a sustained manner for 3 weeks. Histological observations showed that electrospun fbrous membranes have excellent biocompatibility and biodegradability. At 2, 4, and 8 weeks after in vivo RCT repair surgery, electrospun fbrous membranes signifcantly increased the area of glycosaminoglycan staining at the tendon-bone interface compared with the control group, and bFGF-PLGA signifcantly improved collagen organization, as measured by birefringence under polarized light at the healing enthesis compared with the control and PLGA groups. Biomechanical testing showed that the electrospun fbrous membrane groups had a greater ultimate load-to-failure and stiffness than the control group at 4 and 8 weeks. The bFGF-PLGA membranes had the highest ultimate load-to-failure, stiffness, and stress of the healing enthesis, and their superiority compared to PLGA alone was signifcant. These results demonstrated that electrospun fbrous membranes aid in cell attachment and proliferation, as well as accelerating tendon-bone remodeling, and bFGF-loaded PLGA fbrous membranes have a more pronounced effect on tendon-bone healing. Therefore, augmentation using bFGF-PLGA electrospun fbrous membranes is a promising treatment for RCT. © 2014 Zhao et al.