A New Resorbable Wrap-Around Implant as an Alternative Nerve Repair Technique

Abstract

Poly-3-hydroxybutyrate (PHB), a bacterial storage product, is available as bioabsorbable sheets and has been used in this study for primary nerve repair. The aim was to assess axonal regeneration following such repair and determine the inflammatory response to PHB. In 20 adult cats, the transected superficial radial nerve was wrapped in PHB sheets, while primary epineural repair was carried out in the contralateral limb. At 6 and 12 months, the repair sites were assessed immunohistochemically for macrophage infiltration and myelinated axons were counted in the distal nerve. Mean macrophage counts across the whole width of the nerve in both groups at 6 and 12 months showed no statistically significant difference. Nor was there any significant difference between the two groups at both time-points in axon counts, axon diameter, myelin thickness and g-ratio. There was a statistically significant increase in fibre diameters at 12 months, indicating that fibres were undergoing continuous maturation.

Hollow fibers made from a poly(3-hydroxybutyrate)/poly-ε-caprolactone blend

“…However, tubular structures made of very soft or fast degrading materials might collapse or kink before regeneration has been completed and will strongly constrict or even obstruct tissue regeneration [15]. Since PHB is a stiff and rather slowly degrading biopolymer, it has received more attention in neuronal regeneration research [11,16,17]. In contrary to time-consuming manual methods providing three dimensional structures via solvent casting methods, dip coating, wrapping of sheets or braiding of fibers around canules, the thermoplastical processability of PHB allows for a fast and continuous production of tube-like structures via melt spinning, which is the most efficient process to produce fibers [7].…”

Morphological and functional evaluation of leg‐muscle reinnervation after coupler coaptation of the divided rat sciatic nerve

“…For example, when absorbable ''sheathing'' materials such as polyglycolic acid (PGA) 25 or poly-b-hydroxybutyrate (PHB) 27 were employed for end-to-end suture sites, no significant advantages were found compared to conventional epineural suture repairs without a sheath. A fibrous capsule was observed at 6 months, when tubes made of PHB were wrapped around divided cat nerves.…”

Poly(3-hydroxybutyrate) and biopolymer systems on the basis of this polyester

“…Более того, нервные окончания и стенки кондуита были пронизаны системой капилляров, т.е. рост и восстановление нервных проводящих каналов сопровождался прогрессирующим ангиогенезом [12].…”

“…Наличие не согласующихся между собой результатов, по-видимому, обусловлено тем, что ПОБ получают путём различных биотехнологических процедур, с различными бактериями-продуцентами, что затрудняет сопоставление характеристик полимерного продукта, и в будущем требует его стандартизации. Кроме того, образцы ПОБ, используемые в исследованиях в зависимости от целей биомедицинского, получаются различного размера и формы и изготавливаются с использованием различной технологии [9][10][11][12][13][14][15]. В связи с этим, понимание механизма его биодеградации и совместимости с организмом, требует определенных обобщений и дальнейшей интенсификации исследований.…”