title: Sleeve bridging of the rhesus monkey ulnar nerve with muscular branches of the pronator teres: multiple amplification of axonal regeneration.
abstract: Multiple-bud regeneration, i.e., multiple amplification, has been shown to exist in peripheral nerve regeneration. Multiple buds grow towards the distal nerve stump during proximal nerve fiber regeneration. Our previous studies have verified the limit and validity of multiple amplification of peripheral nerve regeneration using small gap sleeve bridging of small donor nerves to repair large receptor nerves in rodents. The present study sought to observe multiple amplification of myelinated nerve fiber regeneration in the primate peripheral nerve. Rhesus monkey models of distal ulnar nerve defects were established and repaired using muscular branches of the right forearm pronator teres. Proximal muscular branches of the pronator teres were sutured into the distal ulnar nerve using the small gap sleeve bridging method. At 6 months after suture, two-finger flexion and mild wrist flexion were restored in the ulnar-sided injured limbs of rhesus monkey. Neurophysiological examination showed that motor nerve conduction velocity reached 22.63 ± 6.34 m/s on the affected side of rhesus monkey. Osmium tetroxide staining demonstrated that the number of myelinated nerve fibers was 1,657 ± 652 in the branches of pronator teres of donor, and 2,661 ± 843 in the repaired ulnar nerve. The rate of multiple amplification of regenerating myelinated nerve fibers was 1.61. These data showed that when muscular branches of the pronator teres were used to repair ulnar nerve in primates, effective regeneration was observed in regenerating nerve fibers, and functions of the injured ulnar nerve were restored to a certain extent. Moreover, multiple amplification was subsequently detected in ulnar nerve axons.
authors: Department of Trauma and Orthopedics, Peking University People's Hospital, Beijing, China.
authors: Yu-Hui
authors: YH
authors: Kou
authors: Department of Trauma and Orthopedics, Peking University People's Hospital, Beijing, China.
authors: Pei-Xun
authors: PX
authors: Zhang
authors: Department of Trauma and Orthopedics, Peking University People's Hospital, Beijing, China.
authors: Yan-Hua
authors: YH
authors: Wang
authors: Department of Trauma and Orthopedics, Peking University People's Hospital, Beijing, China.
authors: Bo
authors: B
authors: Chen
authors: Department of Trauma and Orthopedics, Peking University People's Hospital, Beijing, China.
authors: Na
authors: N
authors: Han
authors: Department of Trauma and Orthopedics, Peking University People's Hospital, Beijing, China.
authors: Feng
authors: F
authors: Xue
authors: Department of Trauma and Orthopedics, Peking University People's Hospital, Beijing, China.
authors: Hong-Bo
authors: HB
authors: Zhang
authors: Department of Trauma and Orthopedics, Peking University People's Hospital, Beijing, China.
authors: Xiao-Feng
authors: XF
authors: Yin
authors: Department of Trauma and Orthopedics, Peking University People's Hospital, Beijing, China.
authors: Bao-Guo
authors: BG
authors: Jiang
keywords: NSFC grants; multiple amplification; muscular branches of pronator teres; nerve regeneration; neural regeneration; peripheral nerve; rhesus monkey; sleeve bridging; small gap; ulnar nerve