Comparison of Results Following Nerve Repair Using Tubulization with or Without a Short Gap in Rabbit Radial Nerve Model

严重的神经损伤通常很难适当地匹配和贴合近端和远端的纤维。由于纤维的混杂，更近端的病变更加困难。最近的研究强烈表明，神经营养因子可以诱导近端的运动神经纤维或感觉神经纤维再生到匹配的特定末端器官。我们比较了在兔正中神经有或没有小间隙的情况下进行管状神经修复的结果。新西兰大白兔40只，分为4组。在主干神经的分支处使用了桡侧感觉神经和运动支(骨间后神经)。对侧径神经作为对照。A组切断感觉支和运动支，用5 mm长的胶原胶粘合。B组除神经旋转180ﾟ外，其余同A组。C组与A组相同，但使用10 mm长的胶原管，在…处留有5 mm的间隙更多的接合部位。D组，管长10 mm，间隙5 mm，神经残端旋转180ﾟ，术后24周分别测量感觉支和运动支的神经传导速度和复合动作电位面积。测定修复侧指总伸肌的收缩力和肌重；随后立即对健侧前肢进行相同的评估。结果以正常对照组百分比表示，神经传导速度和复合动作电位面积组间差异无统计学意义。B组肌力(45.7%)明显低于其他组。D组(97.7%)的肌力与A组(93.6%)或C组(111.4%)相当。干肌重量与肌收缩力有很好的相关性，但组间无显著差异。神经吻合与错位的神经纤维排列不能实现充分的功能恢复。然而，如果在近端和远端神经残端之间提供一个封闭的、小的间隙，则未对准的近端神经纤维可能会检测到远端纤维连接到匹配的靶器官，这可能是通过神经营养因子的帮助。使用可生物降解的短间隙惰性管修复近端神经损伤可能是一种有用的、临床适用的方法。较少

Major nerve injuries are often difficult to appropriately match and coapt proximal and distal fibers. More proximal lesions are even more difficult due to intermingling of the fibers. Recent investigations strongly suggests that neurotropic factor induces proximal motor or sensory nerve fibers to regenerate to the matched specific end organ.We compared the results following nerve repair using tubulization with or without a small gap in rabbit median nerve.Forty New Zealand white rabbits were divided into four groups. The radial sensory nerve and motor branch (posterior interosseous nerve) were used at their branching site from the trunk nerve. The contralateral radial nerve served as the control. In group A, both sensory and motor branches were severed and coapted using a 5-mm-long collagen. In group B, the same procedure was performed as Group A except nerves were rotated 180ﾟ. In Group C, the same procedure as Group A, but a 10-mm-long collagen tube was used and 5-mm gap left at the … More coaptation site. Group D, had 10-mm long tube, 5mm gap and nerve stumps rotated 180ﾟ, At 24 weeks postoperatively, nerve conduction velocities, compound action potential area were obtained from the both the sensory and motor branches. Contraction force and muscle weight of the extensor digitorum communis were determined on the repaired side ; this was followed immediately by identical evaluation on the contralateral forelimb. The results were expressed as the Percentage of normal control.Nerve conduction velocity and compound action potential area did not demonstrate statistically significant differences between groups. Muscle power of group B (45.7%) was significantly less than that of any other groups. Group D (97.7%) recorded comparable muscle power to that of group A (93.6%) or C(111.4%). Dry muscle weight demonstrated good correlation with the muscle contraction force, however, there was no significant difference between groups.Nerve coaptation with misdirected nerve fiber alignment does not allow sufficient functional recovery. If a closed, small gap between the proximal and distal nerve stumps is provided, however, misaligned proximal nerve fiber may detect a distal fiber connecting to the matched target organ probably by the aid of neurotropic factors. Nerve repair using biodegradable, inert tubing with a short gap may be a useful, clinically applicable method in proximal nerve injury. Less