Biopolymers, such as poly(ε-caprolactone), can be easily electrospun to create fibrous scaffolds. It is also possible to control the alignment of the emitted fibres and further manipulate these scaffolds to create 3D yarn structures, which resemble part of the tendon tissue hierarchy. Material properties, such as tensile strength, can be tailored depending on the selection and combination of polymer and solvent used during electrospinning. The scaffolds have been proven to separately support the adhesion and proliferation of equine tendon fibroblasts and human mesenchymal stem cells whilst simultaneously directing cell orientation, which caused their alignment parallel to the underlying fibres. Implantation of scaffolds into the flexor digitorum profundus tendon of mice hindpaws yielded encouraging results with minimal inflammatory reaction and observation of cell infiltration into the scaffold. This research demonstrates the progression of electrospun fibres along the clinical roadmap towards becoming a future medical device for the treatment of tendon injuries. 1. Introduction Electrospinning has become a popular technique in the field of biomaterials and tissue engineering due to the ease at which fibrous scaffolds can be fabricated. The ability to control fibre properties and create 3D structures, with architectures similar to the extracellular matrix, lends itself to a range of tissues, including bone, heart valves, trachea, and tendons [1]. As highly fibrous tissues that repeatedly transfer loads from muscle to bone, tendons are susceptible to wear and tear and spontaneous rupture. Depending on the injury sustained, surgeons can opt to repair the area of damage with autologous tendon tissue. Whilst this is classed as the “gold standard” intervention, it is not without its disadvantages: creation of a secondary site of tissue morbidity arises which can increase the risk of infection and prolong patient rehabilitation time; the ability to source suitable tissue to provide an autograft cannot be guaranteed. Consequently, alternative therapies using biomaterials are being explored. There are a number of commercially available products that aim to repair damaged tendons including Teno Fix manufactured by Ortheon Medical, which is a permanent stainless steel anchor and suture system; Poly-Tape/AchilloCord produced by Xiros (Neoligaments), which is a dense, woven network of nondegradable synthetic polymer; and TissueMend, similar to a number of available devices, which functions as a wrap made of collagen from fetal bovine dermis to be placed around the
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