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Polyurethane as a strategy for annulus fibrosus repair and regeneration: a systematic review.

AIM
Disc herniation is a spine disease that leads to suffering and disability. Discectomy is a Janus-faced approach that relieves pain symptoms but leave the intervertebral discs predisposed to herniation. This systematic review discussed the mechanical and biological requirements for a polyurethane-based biomaterial to be used in annular repair.


METHODS
Search strategy was performed in PubMed, Web of Science and Scopus databases to define the main mechanical properties, biological findings and follow-up aspects of these biomaterials. The range was limited to articles published from January 2000 to December 2017 in English language.


RESULTS
The search identified 82 articles. From these, a total of 18 articles underwent a full-text analysis, and 16 studies were included in the review.


CONCLUSION
The polyurethane presents suitable properties to be used as an engineered solution to re-establish the microenvironment and biomechanical features of the intervertebral disc.