Biodegradable Polymer Grafts for Surgical Repair of the Injured Spinal Cord

PURPOSE Biodegradable polymers have been used in the surgical repair of peripheral nerves, but their potential for use in the central nervous system has not been exploited adequately. This article discusses concepts related to the engineering of a biodegradable polymer graft for surgical repair of the injured spinal cord and explores the potential means by which such a device might promote axon regeneration and functional recovery after spinal cord injury. CONCEPT A biodegradable polymer implant with controlled microarchitecture can be engineered, and its composition can be optimized for implantation in the spinal cord. RATIONALE The use of a biodegradable polymer implant has the dual advantages of providing a structural scaffold for axon growth and a conduit for sustained-release delivery of therapeutic agents. As a scaffold, the microarchitecture of the implant can be engineered for optimal axon growth and transplantation of permissive cell types. As a conduit for the delivery of therapeutic agents that may promote axon regeneration, the biodegradable polymer offers an elegant solution to the problems of local delivery and controlled release over time. Thus, a biodegradable polymer graft would theoretically provide an optimal structural, cellular, and molecular framework for the regrowth of axons across a spinal cord lesion and, ultimately, neurological recovery. CONCLUSION Biodegradable polymer grafts may have significant therapeutic potential in the surgical repair of the injured spinal cord. Further research should be focused on the bioengineering, characterization, and experimental application of these devices.

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