应用神经转位重建足底感觉功能

Reconstruction of the sensory function of the sole by nerve transfer

[目的]探讨神经转位方法重建足底感觉功能的效果。[方法]对足踝以下感觉均丧失者，选用隐神经为供体神经：于小腿中上1／3内后缘作纵行切口长约10cm，于皮下分离出隐神经后切断。于胫骨内后缘分开小腿三头肌显露胫神经，切断部分神经纤维后将隐神经近断端植入其中后行束外膜联合缝合。对于足背及外侧感觉存在而足底足趾感觉丧失者，选用腓肠神经作为供体神经：于外踝后缘向远端行纵切口长约5cm，游离出腓肠神经切断。内踝后方作长约5cm弧形切口，显露胫神经，切开神经外膜并切断部分神经纤维。于跟腱前方间隙打通隧道，将腓肠神经经隧道引至胫神经切开处植入，行束外膜联合缝合。[结果]本组9例患者均得到术后1．5～2年（平均21个月）的随访，顺向电生理检测法测定胫神经感觉传导速度为36．1～41．2（平均38．3）m／s：波幅（峰-峰波幅）在7～15．3μV（平均11．2μV）。9例患者均恢复了足底部痛、触觉。3例患者的两点辨别觉恢复正常。所有患者对行走过程满意，基本无定位错觉等不适情况。所有患者的足部肌肉未出现萎缩。神经供区感觉缺失在腓肠神经者只出现在外踝下方足的外侧区，在隐神经者出现在踝前方的小片区域，对下肢的功能无影响。[结论]应用神经转位的方法可有效的重建足底感觉功能。

[ Objective ] To evaluate the efficacy of nerve transfer for reconstructing the sensory function of the sole. [ Method ] （ 1 ） Select saphenous nerve as donor nerve for the patients with the sensory loss beneath ankle level ： dissect and cut off the saphenous nerve at the medialposterior aspect at upper-middle 1/3 of the leg and divide the gastrocnemius to expose the tibial nerve at the medialposterlor aspect of the tibia, cut off partly nerve fibre of the tibial nerve and then end-to-end anastomose to the proximal end of the saphenous nerve. （2） Select sural nerve as donor nerve for the patients with sensory loss of sole only ： dissect and cut off the sural nerve at the posterior aspect of the lateral malleolus, expose the tibial nerve at the posterior aspect of the medial malleolus and then cut off partly nerve fibre of the tibial nerve. The sural nerve was comdicted from the subcutaneous tunel at the anterior aspect of the Achilles＇s tendon to the posterior aspect of the medial malleolus and end-to-end anastomose to the partial nerve fibre of the tibial nerve. [ Result] All the 9 cases were followed up from 1.5 to 2 years（ mean 2 1 months）. The SCV （ sensory conduction velocity） of the tibial nerve was ranged from 36.1 to 41.2 m/s, mean 38.3 m/s and the amplitude of wave （peak-to-peak amplitude） was a range from 7 to 15.3μN, mean 11.2 μV by orthodromic electrophysiologic techniques. All 9 cases regained the sense of pain and touch of the sole. Three cases restored their sense of two point discrimination. All the patients expressed their satisfaction with their ability of walk and no muscles atrophy of the foot. The sensory loss in donor region was oberserved only lateral part of the foot beneath the lateral malleolus （sural nerve as donor nerve） and a small part of the anterior aspect of the ankle （ saphenous nerve as donor nerve）. [ Conclusion] Nerve transfer can reconstruct the sensory function of the sole effectively.