Short-Term Collagen Nerve Wrapping Facilitates Motor and Sensory Recovery from Nerve Degeneration in a Sciatic Nerve Injury Rat Model

Abstract

Purpose

This study used a sciatic nerve injury rat model to investigate the short-term effects of a polyglycolic acid (PGA)-collagen tube for nerve injury in continuity.

Materials and Methods

Sixteen female Wistar rats (6–8 weeks) were used, and the left sciatic nerve was crushed with a Sugita aneurysm clip. Sciatic nerve model rats were randomly categorized into two groups (n = 8; control group, n = 8; nerve wrapping group). Then, we measured four sensory thresholds, magnetically stimulated the lumbar region to induce motor-evoked potentials (MEPs), and evaluated the sciatic nerve histopathologically.

Results

In the sensory thresholds, there were significant differences for the main effect in 250 and 2000 Hz stimulation (p = 0.048 and 0.006, respectively). Further, a significant difference was observed with 2000 Hz stimulation at 1 week (p = 0.003). In the heat stimulation, there were significant differences for the main effect in both weeks and groups (p = 0.0002 and 0.0185, respectively). The post-hoc test showed a significant difference between groups only in 2W (p = 0.0283). Three weeks after the surgery, both 2nd and 3rd MEPs waves-related latencies in the nerve wrapping group were significantly shorter than those in the control group (p = 0.0207 and 0.0271, respectively). Histological evaluation of the sciatic nerve revealed considerable differences in the number of axons between the two groups (p = 0.0352).

Conclusion

The short-term PGA-collagen tube nerve wrapping facilitated motor and sensory recovery from nerve degeneration in the sciatic nerve injury rat model.

Keywords:

• polyglycolic acid-collagen tube
• nerve wrapping
• sciatic nerve injury
• sensory threshold
• motor and sensory recovery

Acknowledgments

We thank Dr. Hiroharu Koga (Kumamoto Health Science University), Mr. Yasuyuki Teramoto (Kumamoto Kinoh Hospital), Mr. Tsukasa Kajihara (Miyuki Giken Kyusyu Co.) Dr. Kazuyuki Oda (Inrercross Co.), Mr. Soma Yamamoto (Bio Research Center Co. Ltd.) and Mr. Kazuyoshi Morita (Bio Research Center Co. Ltd.) for useful technical advice regarding the MEP experiment. This work is supported by both JPJS KAKENHI Grant Numbers 26350646 (AD) and 19K11383 (AD) and Kumamoto Health Science University special fellowship grant number 2020-C-02 (AD).

Disclosure

The authors report no conflicts of interest in this work.