First investigation of spider silk as a braided microsurgical suture

Abstract

Inhibition of axonal outgrowth accompanied by neuroma formation appears in microsurgical nerve repair as reaction to common microsuture materials like silk, nylon, or polyglycolic acid. In contrast, recent findings revealed advantages of spider silk fibers in guiding Schwann cells in nerve regeneration. Here, we asked if we could braid microsutures from native spider silk fibers. Microsutures braided of native spider dragline silk were manufactured, containing either 2 × 15 or 3 × 10 single fibres strands. Morphologic appearance was studied and tensile strength and stress-strain ratio (SSR) were calculated. The constructed spider silk sutures showed a median thickness of 25 μm, matching the USP definition of 10-0. Maximum load and tensile strength for both spider silk microsutures were significantly more than 2-fold higher than for nylon suture; SSR was 1.5-fold higher. All values except elasticity were higher in 3 × 10 strand sutures compared to 2 × 15 strand sutures, but not significantly. In this pilot study, we demonstrate the successful manufacture of microsutures from spider silk. With regards to the mechanical properties, these sutures were superior to nylon sutures. As spider silk displays high biocompatibility in nerve regeneration, its usage in microsurgical nerve repair should be considered.

Spider Silk as Guiding Biomaterial for Human Model Neurons

“…Stress level for animals was kept to an absolute minimum and no harming occurred during the harvesting process. For this purpose spiders were fixed with gauze and needles to a styropor pad without anesthesia as already described [7]. For dragline silk collection, the silk was pulled out of the major ampullate gland with forceps.…”

Biomechanics and Biocompatibility of Woven Spider Silk Meshes During Remodeling in a Rodent Fascia Replacement Model

“…Concerning its biomechanical performance, Kuhbier et al 37 already published data showing that manufactured spider silk sutures with higher stress to strain ratio and more than 2-fold higher tensile strength than nylon sutures being the current clinical gold standard for nerve repair. 37 The spider silk meshes tested in this study displayed slightly higher values for tensile strength than sham-operated fasciae but much lower values than Ultrapro for the whole observation period. Surgisis was solely marginally stronger than spider silk after 4 days; subsequently, it showed negligible lower values.…”

Natural Occurring Silks and Their Analogues as Materials for Nerve Conduits

“…However, these issues have been resolved and relatively large amounts of spider silk can be harvested. The use of native spider silk has been successfully established as a biomaterial for nerve regeneration and other biomedical applications [47,48,61,62,63,64,65,66,67,68]. As a first step for the development of a spider silk-based nerve conduit, a breeding station for spiders of the genera Nephila clavipes was build and processing parameters of native spider silk were established.…”

“…As a first step for the development of a spider silk-based nerve conduit, a breeding station for spiders of the genera Nephila clavipes was build and processing parameters of native spider silk were established. Procedures were developed to harvest the native dragline silk directly from the adult female spiders in relatively large quantities [61]. …”