Long-term evaluation of functional nerve recovery after reconstruction with a thin-walled biodegradable poly (DL-Lactide-?-caprolactone) nerve guide, using walking track analysis and electrostimulation tests

Abstract

This study was performed to evaluate the long-term functional nerve recovery after reconstruction of a 10-mm gap in the sciatic nerve of the rat, with a thin-walled nerve guide, composed of a biodegradable copolymer of DL-lactide and epsilon-caprolactone [p(DLLA-epsilon-CL)]. To evaluate both motor and sensory nerve recovery, walking track analysis and electrostimulation tests were carried out after implantation periods ranging from 3 to 52 weeks postoperatively. The first signs of both motor and sensory nerve recovery could be observed after 5 weeks. After 15 weeks, 70% of the sciatic function and 90% of the sensory nerve function had been recovered. After this period, the sciatic function index (SFI) did not improve further, whereas the sensory nerve function appeared to return to normal. When the results of the SFI measurements, minus those obtained from rats with severe automutilation, are extrapolated, further improvement of the SFI might be expected after 52 weeks. The fact that 100% sensory nerve recovery was obtained, as measured by the electrostimulation test, could be explained by sensory reinnervation from surrounding areas. The SFI was not fully reestablished because automutilation had a great impact on the use of walking track assessment.

CatWalk gait analysis in assessment of functional recovery after sciatic nerve injury

“…), and histomorphometrical tests (myelin thickness, axon diameter, fiber density, etc.) (Luis et al, 2007;Meek et al, 1999;Varejao et al, 2004a,b). The CatWalk system has some drawbacks, such as requiring (i) a darkened room for testing and (ii) the need for a 2-week training period for the animals.…”

“…Likewise, many experimental repair therapies have been tested for their effect on peripheral axon regeneration (Belkas et al, 2004;Bozkurt et al, 2007) and, ultimately, functional recovery (Meek et al, 1999;Pfister et al, 2007;Varejao et al, 2001Varejao et al, , 2004bVleggeert-Lankamp, 2007;Wang et al, 2008). Indispensable in assessment of the functionality of axon regeneration is the use of tests that sensitively detect functional recovery.…”

Evaluation of functional nerve recovery with Visual-SSI—A novel computerized approach for the assessment of the static sciatic index (SSI)

“…In prior studies, using the sciatic nerve model, both SFI and SSI analyses were hampered by autotomy and contracture (Bervar, 2000;Den Dunnen and Meek, 2001;Meek et al, 1999).…”

Hyaluronic acid-based scaffold for central neural tissue engineering

“…There have been many studies on repair of the PNS by tubes or nerve guides, with some promising results observed [31,32]. These anisotropic structures offer physical guidance to the migration of cells and the penetration of axons.…”