Biologic Patches for Management of Irreparable Rotator Cuff Tears

Modulating cell adhesion to polybutylene succinate biotextile constructs for tissue engineering applications

Textile-based technologies are powerful routes for the production of three-dimensional porous architectures for tissue engineering applications because of their feasibility and possibility for scaling-up. Herein, the use of knitting technology to produce polybutylene succinate fibre-based porous architectures is described. Furthermore, different treatments have been applied to functionalize the surface of the scaffolds developed: sodium hydroxide etching, ultraviolet radiation exposure in an ozone atmosphere and grafting (acrylic acid, vinyl phosphonic acid and vinyl sulphonic acid) after oxygen plasma activation as a way to tailor cell adhesion. A possible effect of the applied treatments on the bulk properties of the textile scaffolds has been considered and thus tensile tests in dry and hydrated states were also carried out. The microscopy results indicated that the surface morphology and roughness were affected by the applied treatments. The X-ray photoelectron spectroscopy and contact angle measurements showed the incorporation of oxygen-containing groups and higher surface free energy as result of the surface treatments applied. The DNA quantification and scanning electron microscopy analysis revealed that these modifications enhanced cell adhesion and altered cell morphology. Generally, sodium hydroxide treatment altered most significantly the surface properties, which in turn resulted in a high number of cells adherent to these surfaces. Based on the results obtained, the proposed surface treatments are appropriate to modify polybutylene succinate knitting scaffolds, influencing cell adhesion and its potential for use in tissue engineering applications. Copyright © 2016 John Wiley & Sons, Ltd.

Effective healing of chronic rotator cuff injury using recombinant bone morphogenetic protein-2 coated dermal patch in vivo

Biologic augmentation for rotator cuff repair is a challenging treatment in patients with chronic large, massive, and irreparable rotator cuff injuries. Particularly, the use of an extracellular matrix (ECM) patch such as dermal tissue offered improved biomechanical properties in previous studies. Cytokines induce cell chemotaxis, proliferation, matrix synthesis, and cell differentiation. Moreover, osteoinductive growth factors such as bone morphogenetic protein-2 (BMP-2) affect the formation of new bone and fibrocartilage in lesions. However, the effects of using a dermal patch in combination with BMP-2 have not been evaluated to date, although many researchers have recognized the importance thereof. In this study, rhBMP-2-coated dermal patch (1 cm × 2 cm) isolated from human cadaveric donor was inserted in a rabbit model of chronic rotator cuff injury for in vivo evaluation. Bone mineral density and biomechanical strength were tested and histological and histomorphometric analyses were performed. The results showed that insertion of an rhBMP-2-coated acellular dermal patch not only significantly ameliorated new bone formation, it also improved biomechanical properties such as ultimate tensile strength. Thus, the use of this combination may improve the chronic rotator cuff injury-healing rate and clinical outcomes after rotator cuff repair. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1840-1846, 2017.