A Review of Bioactive Release from Nerve Conduits as a Neurotherapeutic Strategy for Neuronal Growth in Peripheral Nerve Injury
Degeneration and regeneration after peripheral nerve injury. (a) Normal neuron and nerve fiber. (b) Wallerian degeneration. The axotomy results in fragmentation of the distal axon and myelin sheaths. Schwann cells proliferate and macrophages invade the distal nerve segment and phagocytose degrading materials. (c) Schwann cells in the distal segment line up in bands of Büngner. Axonal sprouts advance embedded in the Schwann cells and attracted by gradients of neurotrophic factors. (d) Axonal reconnection with end organs and maturation and remyelination of the nerve fiber  (reproduced with permission from Elsevier B.V. Ltd., 2010).