title: The longitudinal epineural incision and complete nerve transection method for modeling sciatic nerve injury.
abstract: Injury severity, operative technique and nerve regeneration are important factors to consider when constructing a model of peripheral nerve injury. Here, we present a novel peripheral nerve injury model and compare it with the complete sciatic nerve transection method. In the experimental group, under a microscope, a 3-mm longitudinal incision was made in the epineurium of the sciatic nerve to reveal the nerve fibers, which were then transected. The small, longitudinal incision in the epineurium was then sutured closed, requiring no stump anastomosis. In the control group, the sciatic nerve was completely transected, and the epineurium was repaired by anastomosis. At 2 and 4 weeks after surgery, Wallerian degeneration was observed in both groups. In the experimental group, at 8 and 12 weeks after surgery, distinct medullary nerve fibers and axons were observed in the injured sciatic nerve. Regular, dense myelin sheaths were visible, as well as some scarring. By 12 weeks, the myelin sheaths were normal and intact, and a tight lamellar structure was observed. Functionally, limb movement and nerve conduction recovered in the injured region between 4 and 12 weeks. The present results demonstrate that longitudinal epineural incision with nerve transection can stably replicate a model of Sunderland grade IV peripheral nerve injury. Compared with the complete sciatic nerve transection model, our method reduced the difficulties of micromanipulation and surgery time, and resulted in good stump restoration, nerve regeneration, and functional recovery.
authors.affiliation: Department of Hand and Foot Surgery, Affiliated Hospital of Chengde Medical University, Chengde, Hebei Province, China.
authors.forename: Xing-Long
authors.initials: XL
authors.lastname: Cheng
authors.affiliation: Department of Hand and Foot Surgery, Affiliated Hospital of Chengde Medical University, Chengde, Hebei Province, China.
authors.forename: Pei
authors.initials: P
authors.lastname: Wang
authors.affiliation: Department of Hand and Foot Surgery, Affiliated Hospital of Chengde Medical University, Chengde, Hebei Province, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Sun
authors.affiliation: Department of Hand and Foot Surgery, Affiliated Hospital of Chengde Medical University, Chengde, Hebei Province, China.
authors.forename: Shi-Bo
authors.initials: SB
authors.lastname: Liu
authors.affiliation: Department of Hand and Foot Surgery, Affiliated Hospital of Chengde Medical University, Chengde, Hebei Province, China.
authors.forename: Yun-Feng
authors.initials: YF
authors.lastname: Gao
authors.affiliation: Graduate School of Chengde Medical University, Chengde, Hebei Province, China.
authors.forename: Xin-Ze
authors.initials: XZ
authors.lastname: He
authors.affiliation: Department of Hand and Foot Surgery, Affiliated Hospital of Chengde Medical University, Chengde, Hebei Province, China.
authors.forename: Chang-Yu
authors.identifier: 0000-0003-4107-2265
authors.initials: CY
authors.lastname: Yu
keywords: Sunderland IV; animal models; longitudinal epineural incision; nerve regeneration; nerve regeneration and repair; neural regenerati; peripheral nerve; rats; sciatic nerve injury