Fibre-based scaffolding techniques for tendon tissue engineering

Tendon refers to a band of tough, regularly arranged, and connective tissue connecting muscle and bone, transferring strength from muscle to bone, and enabling articular stability and movement. The limitations of natural tendon grafts motivate the scaffold-based tissue engineering (TE) approaches, which aim to build patient-specific biological substitutes that can repair the damaged or diseased tissues. Advances in engineering and knowledge of chemistry and biology have brought forth numerous fibre-based technologies, including electrospinning, electrohydrodynamic jet printing, electrochemical alignment technique, and other fibre-assembly technologies, which enable the fabrication of tendon tissue structure in 3-dimension. Textile techniques such as knitting and braiding have also been performed based on the fibrous materials to produce more complex structure. These scaffolds showed great similarity with native tendons in architectural features, mechanical properties, and facilitate biological functionality such as cellular adhesion, ingrowth, proliferation, and differentiation towards tendon tissue. Herein, we review the techniques that have been used to assemble fibres into scaffolds for tendon TE application. The morphological structures, mechanical properties, materials, degradation characteristics, and biological activities of the induced scaffolds were compared. The existing challenges and future prospects of fibre-based tendon TE have also been discussed.