Injuries of the peripheral nervous system lead to impairments in motor and sensory functions, compromising the patients’ quality of life. Autologous nerve grafting is a surgical solution, but it is not well accepted because of limited tissue availability and harvest surgery complications. In the recent years, the repair of large nerve defects is addressed through tissue engineering strategies. Bioengineered nerve guidance scaffolds/conduits prepared from polymers provide platform for the defective nerve stumps to grow and attach to restore the lost functions. This area has advanced significantly now, with some products demonstrating the bridging of large nerve gaps in pre-clinical trials. Successful translation of such nerve regenerating products toward clinical applications is awaited. This review primarily highlights the role of polymeric materials and tissue engineering in the repair of peripheral nerve injuries. Scaffold design strategies for nerve regeneration have been extensively covered in the literature. The focus is on the evaluation of the functional performance of various nerve guidance scaffolds/conduits, demonstrated through in vitro tests and preclinical animal studies. The initial sections of this review provide an overview of the structure and functions of peripheral nerves. Subsequent sections include a detailed survey of tissue engineering strategies for nerve regeneration, covering the role of the polymeric materials also. Scaffold evaluation further strengthens this foundation, with in vitro studies ensuring safety and in vivo models confirming efficacy. Animal trials, carefully designed to reflect real clinical conditions, will offer crucial insights into scaffold performance, enabling confident progression toward human applications. In the final part, the current clinical landscape and future perspectives are outlined. The success achieved at present in the in vitro validation of tissue-engineered nerve guidance scaffolds necessitates comprehensive pre-clinical and human evaluations to generate the evidence required for their translation into clinically usable products.
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