鄒秀強(qiáng),梁向黨,郭占芳,孫 賡,余寬寬,房卓群
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·論著·
醫(yī)用膠制動對大鼠坐骨神經(jīng)離斷吻合修復(fù)效果影響研究
鄒秀強(qiáng),梁向黨*,郭占芳*,孫 賡,余寬寬,房卓群
目的 觀察醫(yī)用膠制動對大鼠坐骨神經(jīng)離斷吻合修復(fù)效果的影響。方法 選用健康雄性SD大鼠30只,造模成功后隨機(jī)分為兩組,每組各15只。實(shí)驗(yàn)組于坐骨神經(jīng)中點(diǎn)處離斷后手術(shù)顯微鏡下行傳統(tǒng)針線縫合吻合,硅膠導(dǎo)管套在吻合口表面,導(dǎo)管中點(diǎn)與吻合口位置相同,導(dǎo)管兩端口各滴20 μl醫(yī)用粘合劑固定。對照組于坐骨神經(jīng)中點(diǎn)處離斷后僅行手術(shù)顯微鏡下傳統(tǒng)針線縫合吻合,未使用醫(yī)用膠和導(dǎo)管固定。術(shù)后第8周對吻合口神經(jīng)結(jié)締組織行大體觀察、神經(jīng)功能指數(shù)、電生理檢查和組織病理學(xué)觀察,分別記錄神經(jīng)外膜內(nèi)、外結(jié)締組織增生情況,觀測吻合口神經(jīng)纖維再生數(shù)量。結(jié)果 術(shù)后第8周,大體觀察:兩組大鼠神經(jīng)與周圍組織粘連明顯,但實(shí)驗(yàn)組坐骨神經(jīng)分離容易;實(shí)驗(yàn)組左側(cè)坐骨神經(jīng)功能指數(shù)(6、8周)、神經(jīng)潛伏期、神經(jīng)外膜瘢痕結(jié)締組織最大厚度、4個視野神經(jīng)內(nèi)結(jié)締組織面積之和均小于對照組(P<0.05);神經(jīng)振幅、神經(jīng)纖維再生計(jì)數(shù)大于對照組(P<0.05)。結(jié)論 神經(jīng)離斷后使用醫(yī)用膠對神經(jīng)制動,可以抑制吻合口疤痕結(jié)締組織的增生,促進(jìn)神經(jīng)纖維的再生。
氰丙烯酸鹽類,制動,修復(fù);坐骨神經(jīng);大鼠
周圍神經(jīng)離斷性損傷是臨床工作中常見的疾病,也是神經(jīng)損傷中嚴(yán)重的一種類型。神經(jīng)顯微吻合是治療神經(jīng)離斷損傷的金標(biāo)準(zhǔn)[1]。有提出張力對神經(jīng)再生是有害的,神經(jīng)離斷性損傷后,神經(jīng)內(nèi)外纖維結(jié)締組織增生,使吻合口生長牢固以消除張力的不良影響[2-3]。但是結(jié)締組織的過度增生干擾了軸突再生、軸漿運(yùn)輸以及局部的血液循環(huán),制約了神經(jīng)再生和靶器官功能恢復(fù),致使患者感覺和運(yùn)動功能部分喪失[4-6]。為抑制神經(jīng)內(nèi)外結(jié)締組織的增生,許多學(xué)者提出對損傷肢體進(jìn)行制動,以減少吻合口的力學(xué)刺激,促進(jìn)神經(jīng)再生。肢體的制動又帶來關(guān)節(jié)攣縮、肌肉萎縮,從而不利于患者的康復(fù)[7-10]。因此對肢體制動的方法、制動的時間、甚至是否需要制動,學(xué)術(shù)界仍然存在較大的爭議。本文通過使用醫(yī)用膠粘劑和硅膠導(dǎo)管,在大鼠坐骨神經(jīng)離斷吻合口,對其采取內(nèi)固定制動,消除神經(jīng)再生過程中張力對吻合口的刺激,通過術(shù)后組織病理學(xué)觀察吻合口內(nèi)外結(jié)締組織增生的情況,以及神經(jīng)功能恢復(fù)的評價,了解神經(jīng)內(nèi)制動因素對吻合口結(jié)締組織增生和神經(jīng)功能恢復(fù)的影響。
1.1 實(shí)驗(yàn)動物和材料 健康雄性SD大鼠30只,體重300~350 g,由解放軍總醫(yī)院動物中心提供[(SCXK(京)2012-0001];α-氰基丙烯酸酯醫(yī)用粘合劑(廣州白云醫(yī)用膠有限公司);普通硅膠導(dǎo)管(長10 mm、內(nèi)徑1.5 mm);丹麥產(chǎn)Medtronic Keypoint肌電圖儀。
1.2 模型制備與分組 1%戊巴比妥鈉腹腔注射麻醉后(40 mg/kg),大鼠右側(cè)臥位固定于手術(shù)臺上,通過左側(cè)股骨后外側(cè)肌間隙為入口暴露坐骨神經(jīng),運(yùn)用手術(shù)顯微鏡仔細(xì)游離坐骨神經(jīng),近端位于梨狀肌出口,遠(yuǎn)端達(dá)腓總神經(jīng)分支上緣2 mm處(注意保護(hù)好腓總神經(jīng));使用顯微剪在坐骨神經(jīng)中點(diǎn)處離斷。造模成功后,將30只SD大鼠隨機(jī)分為實(shí)驗(yàn)組與對照組,每組各15只,實(shí)驗(yàn)組用10-0顯微縫線借助手術(shù)顯微鏡外膜縫合6針,硅膠導(dǎo)管套接吻合口(導(dǎo)管中點(diǎn)與吻合口重合),導(dǎo)管邊緣各滴20 μl醫(yī)用粘合劑與神經(jīng)固定,待膠水固化后,屈伸左下肢見吻合口在硅膠管內(nèi)無位移現(xiàn)象,吻合口制動滿意;對照組用10-0顯微縫線外膜縫合6針,不做其他處理。待粘合劑固化后,創(chuàng)面均使用慶大霉素沖洗后逐層縫合,大鼠蘇醒后分籠常規(guī)飼養(yǎng)。
1.3 觀察方法
1.3.1 大體觀察:術(shù)后第8周大鼠再次麻醉,切開原切口顯露坐骨神經(jīng),觀察切口內(nèi)有無感染,神經(jīng)表面組織粘連情況及吻合口愈合情況,并詳細(xì)記錄。
1.3.2 神經(jīng)功能指數(shù)(SFI):將大鼠后肢足底涂抹紅色染料,構(gòu)建木制通道并在下方平面附宣紙。待大鼠通過后,測量大鼠在宣紙上留下的足印。主要包括足長、趾寬和中間趾寬。觀察時間點(diǎn)為術(shù)后第2、4、6、8周。再依據(jù)Bain公式[SFI=109.5(ETS-NTS)/NTS-38.3(EPL-NPL)/NPL+13.3(EIT-NIT)/NIT-8.8,其中E代表實(shí)驗(yàn)側(cè),N代表正常側(cè),TS代表第1到第4腳趾距離,PL代表第3腳趾到足印底部距離,IT代表第2到第4腳趾距離]計(jì)算出大鼠坐骨神經(jīng)SFI。數(shù)值為0代表功能正常,數(shù)值為-100代表功能完全喪失。
1.3.3 電生理檢查:標(biāo)本觀察結(jié)束后,使用肌電圖儀進(jìn)行神經(jīng)電生理檢測,將刺激電極放置在吻合神經(jīng)近側(cè)5 mm處,記錄電極放置在小腿脛后肌群上。分別記錄術(shù)后第8周實(shí)驗(yàn)組與對照組坐骨神經(jīng)動作電位的潛伏期和振幅數(shù)值。
1.3.4 組織病理學(xué)觀察:電生理檢查結(jié)束后,吻合口近端和遠(yuǎn)端5 mm處離斷留取標(biāo)本,神經(jīng)近端做標(biāo)記。常規(guī)固定脫水,石蠟包埋。標(biāo)本縱切后分別行HE、Masson染色、吻合口遠(yuǎn)端3 mm處做橫切標(biāo)本鍍銀染色。光學(xué)顯微鏡下(40×),隨機(jī)選取90 μm×90 μm的4個視野并拍照,Image Pro PluS圖像分析系統(tǒng)測量4個視野神經(jīng)內(nèi)結(jié)締組織面積之和;選取神經(jīng)吻合口外結(jié)締組織最厚的部分,并測量其長度。Image Pro PluS圖像分析系統(tǒng)計(jì)數(shù)通過吻合口的神經(jīng)纖維總數(shù),觀察吻合口神經(jīng)再生情況。
2.1 大體觀察 兩組大鼠未出現(xiàn)死亡情況,切口無裂開及感染,術(shù)后第2天大鼠左下肢均出現(xiàn)被動運(yùn)動,所有動物納入結(jié)果分析。術(shù)后第8周大鼠再次麻醉后沿原切口逐層切開,顯露坐骨神經(jīng),兩組神經(jīng)吻合口外觀連續(xù)性完整,未見感染征象;兩組神經(jīng)與周圍組織粘連明顯,實(shí)驗(yàn)組坐骨神經(jīng)分離容易,對照組吻合口與周圍粘連致密,需借助手術(shù)顯微鏡分離。
2.2 神經(jīng)功能指數(shù) 術(shù)后對照組第2、4、6、8周SFI數(shù)值分別為:-92±2.4、-76±2.9、-65±3.7、-56±3.7;術(shù)后實(shí)驗(yàn)組4個時間點(diǎn)SFI數(shù)值分別為:-91±2.6、-74±3.1、-61±4.2、-51±4.1。其中,術(shù)后第2、4周兩組SFI比較差異無統(tǒng)計(jì)學(xué)意義(P>0.05),但術(shù)后第6、8周實(shí)驗(yàn)組SFI均高于對照組(P<0.01)。
2.3 電生理檢測 術(shù)后第8周實(shí)驗(yàn)組與對照組左側(cè)坐骨神經(jīng)潛伏期與振幅比較差異具有統(tǒng)計(jì)學(xué)意義(P<0.05),見表1。
表1 術(shù)后第8周兩組電生理檢測結(jié)果比較
注:實(shí)驗(yàn)組為針線縫合吻合后使用醫(yī)用粘合劑和導(dǎo)管固定,對照組為行針線縫合吻合;與對照組比較,aP<0.05
2.4 組織學(xué)觀察 術(shù)后第8周組織病理學(xué)觀察顯示,對照組吻合口神經(jīng)外膜結(jié)締組織增生明顯,實(shí)驗(yàn)組神經(jīng)外膜結(jié)締組織最大厚度為(368.2±13.1)μm,對照組為(562.8±20.2)μm,兩組比較差異具有統(tǒng)計(jì)學(xué)意義(P<0.05),見圖1。實(shí)驗(yàn)組4個視野神經(jīng)內(nèi)結(jié)締組織面積之和為(14158.8±442.5)μm2,對照組為(18856.8±654.6)μm2,兩組比較差異具有統(tǒng)計(jì)學(xué)意義(P<0.05),見圖2。實(shí)驗(yàn)組吻合口遠(yuǎn)端3 mm處神經(jīng)纖維再生數(shù)量為(4867±262)個,對照組為(4595±304)個,兩組比較差異有統(tǒng)計(jì)學(xué)意義(P<0.05),見圖3。
周圍神經(jīng)損傷后,斷端縫合、神經(jīng)移植依舊是神經(jīng)修復(fù)的金標(biāo)準(zhǔn)。在神經(jīng)修復(fù)早期,神經(jīng)內(nèi)外瘢痕結(jié)締組織增生明顯,其中含量最高的為Ⅰ、Ⅲ型膠原組織[11]。膠原組織具有很強(qiáng)的抗張力性,在神經(jīng)修復(fù)早期對于消除張力具有重要的意義。但是瘢痕結(jié)締組織在神經(jīng)內(nèi)外過度增生,卻會嚴(yán)重干擾神經(jīng)再生的過程[12]。神經(jīng)外瘢痕結(jié)締組織的過度增生,可以對神經(jīng)吻合口造成機(jī)械性的壓迫,使神經(jīng)外膜微血管血流中斷和軸漿運(yùn)輸障礙,破壞了血-神經(jīng)屏障的功能;神經(jīng)內(nèi)瘢痕結(jié)締組織的過度增生,阻礙軸突穿越吻合口向遠(yuǎn)端生長,嚴(yán)重阻礙了軸突再生和神經(jīng)功能的恢復(fù)[13-14]。這也使得神經(jīng)損傷后修復(fù)的結(jié)局難以預(yù)測。究其原因,吻合口生物力學(xué)刺激是再生過程中的一個重要不良因素。
因此,神經(jīng)離斷性損傷后肢體制動,減少吻合口的力學(xué)刺激是很有必要的,待神經(jīng)吻合口生長牢固后,開始行肢體功能鍛煉[15]。但是肢體的制動會帶來很多負(fù)面影響,如肌肉萎縮、關(guān)節(jié)攣縮甚至關(guān)節(jié)功能喪失。本實(shí)驗(yàn)對神經(jīng)吻合口進(jìn)行內(nèi)制動,在神經(jīng)修復(fù)早期可以完全避免肢體被動活動所帶來的不良影響。一定程度上也可以避免肌肉萎縮、關(guān)節(jié)攣縮和功能喪失,促進(jìn)關(guān)節(jié)、肌肉功能的恢復(fù)。術(shù)后第8周SFI及電生理檢測結(jié)果等數(shù)據(jù)表明,神經(jīng)功能恢復(fù)優(yōu)于對照組;神經(jīng)內(nèi)瘢痕結(jié)締組織面積實(shí)驗(yàn)組明顯小于對照組。這一結(jié)果也與Schmidhammer等[16]的研究結(jié)果相一致。證明了該種方法的可行性,也為神經(jīng)離斷損傷在臨床上治療拓展了新視野。
圖1 術(shù)后第8周兩組大鼠左側(cè)坐骨神經(jīng)吻合口近端鏡下觀察神經(jīng)外膜結(jié)締組織(HE×40)
A.實(shí)驗(yàn)組:針線縫合吻合后使用醫(yī)用粘合劑和導(dǎo)管固定;B.對照組:行針線縫合吻合;紅色標(biāo)記線為吻合口神經(jīng)外膜結(jié)締組織最厚部分
圖2 術(shù)后第8周兩組左側(cè)坐骨神經(jīng)吻合口近端鏡下觀察神經(jīng)內(nèi)結(jié)締組織面積(Masson×400)
A.實(shí)驗(yàn)組:針線縫合吻合后使用醫(yī)用粘合劑和導(dǎo)管固定;B.對照組:行針線縫合吻合;結(jié)締組織顯示為淡藍(lán)色,髓鞘顯示為紅色
圖3 術(shù)后第8周兩組左側(cè)坐骨神經(jīng)吻合口遠(yuǎn)端鏡下觀察神經(jīng)再生(鍍銀染色×400)
A.實(shí)驗(yàn)組:針線縫合吻合后使用醫(yī)用粘合劑和導(dǎo)管固定;B.對照組:行針線縫合吻合
Robert Schmidhammer在實(shí)驗(yàn)中使用縫線固定神經(jīng)和硅膠導(dǎo)管,使得吻合口與導(dǎo)管形成一個整體,達(dá)到制動的效果。但是過多地使用縫合方法,一方面縫針對神經(jīng)有二次損傷,另一方面縫線由外而內(nèi)進(jìn)入神經(jīng)組織,也增加了局部炎癥反應(yīng)的風(fēng)險,導(dǎo)致局部瘢痕結(jié)締組織的增生[17]。粘合劑在神經(jīng)修復(fù)中的使用受到很多學(xué)者的青睞[18-19]。α-氰基丙烯酸脂粘合劑已經(jīng)成熟運(yùn)用于臨床和動物實(shí)驗(yàn),梁向黨等[20]利用該粘合劑成功修復(fù)大鼠坐骨神經(jīng)損傷。在本實(shí)驗(yàn)中還觀察到,20 μl粘合劑固化后不但可以起到粘連作用,它具有很強(qiáng)的抗?fàn)坷饔谩I窠?jīng)吻合口套接硅膠導(dǎo)管,并使用α-氰基丙烯酸脂粘合劑封閉導(dǎo)管,可以對吻合口進(jìn)行有效的內(nèi)制動。醫(yī)用硅膠導(dǎo)管組織相容性好,無抗原性,在人體內(nèi)異物反應(yīng)較小。并且硅膠導(dǎo)管本身所具有的韌性,不僅為神經(jīng)再生提供一個很好的三圍支撐空間,也為神經(jīng)再生提供了一個良好的微環(huán)境。既能避免神經(jīng)營養(yǎng)因子外逸,也能阻止外界結(jié)締組織的入侵。術(shù)后第8周神經(jīng)吻合口外結(jié)締組織厚度的測量結(jié)果表明,硅膠導(dǎo)管可以顯著抑制吻合口外結(jié)締組織的增生。
綜上所述,利用粘合劑和硅膠導(dǎo)管所制備的內(nèi)固定支架,可以對神經(jīng)吻合口起到很好的制動效果。不僅可以抑制神經(jīng)內(nèi)外瘢痕結(jié)締組織的增生,而且還有利于神經(jīng)再生,促進(jìn)神經(jīng)靶器官功能的恢復(fù)。
[1] Kechele P R, Bertelli J A, Dalmarco E M,etal. The mesh repair: tension free alternative on dealing with nerve gaps-experimental results[J].Microsurgery, 2011,31(7):551-558.
[2] Millesi H, Meissl G, Berger A. The interfascicular nerve-grafting of the median and ulnar nerves[J].J Bone Joint Surg Am, 1972,54(4):727-750.
[3] Berger A, Millesi H. Nerve grafting[J].Clin Orthop Relat Res, 1978(133):49-55.
[4] Ngeow W C. Scar less: a review of methods of scar reduction at sites of peripheral nerve repair[J].Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 2010,109(3):357-366.
[5] 殷玉芹,劉正津,何光.張力對周圍神經(jīng)損傷和修復(fù)的影響[J].解剖科學(xué)進(jìn)展,1995,1(1):30-34.
[6] 閆家智,姜保國.周圍神經(jīng)的生物力學(xué)研究進(jìn)展[J].中華實(shí)驗(yàn)外科雜志,2004,21(1):125-126.
[7] Currier D P, Ray J M, Nyland J,etal. Effects of electrical and electromagnetic stimulation after anterior cruciate ligament reconstruction[J].J Orthop Sports Phys Ther, 1993,17(4):177-184.
[8] Jozsa L, Kannus P, J?rvinen M,etal. Atrophy and regeneration of rat calf muscles cause reversible changes in the number of nucleolar organizer regions. Evidence that also in nonproliferating cells the number of NORs is a marker of protein synthesis activity[J].Lab Invest, 1993,69(2):231-237.
[9] Miles M P, Clarkson P M, Bean M,etal. Muscle function at the wrist following 9d of immobilization and suspension[J].Med Sci Sports Exerc, 1994,26(5):615-623.
[10]周俊明,徐曉君,張沈煜,等.臂叢神經(jīng)損傷規(guī)范化康復(fù)治療的臨床研究[J].中國康復(fù)醫(yī)學(xué)雜志,2011,26(2):124-127.
[11]Tersis J K. Principles and techniques of peripheral nerve[J].Surg Clin Orthop Res, 2002,133:139.
[12]Bustamante J, Socolovsky M, Martins R S,etal. Effects of eliminating tension by means of epineural stitches: a comparative electrophysiological and histomorphometrical study using different suture techniques in an animal model[J].Arq Neuropsiquiatr, 2011,69(2B):365-370.
[13]Lane J M, Bora F J, Pleasure D. Neuroma scar formation in rats following peripheral nerve transection[J].J Bone Joint Surg Am, 1978,60(2):197-203.
[14]劉華蔚,胡敏.周圍神經(jīng)瘢痕研究進(jìn)展[J].中華老年口腔醫(yī)學(xué)雜志,2012,10(4):237-240,246.
[15]Henry F P, Farkhad R I, Butt F S,etal. A comparison between complete immobilisation and protected active mobilisation in sensory nerve recovery following isolated digital nerve injury[J].J Hand Surg Eur Vol, 2012,37(5):422-426.
[16]Schmidhammer R, Zandieh S, Hopf R,etal. Alleviated tension at the repair site enhances functional regeneration: the effect of full range of motion mobilization on the regeneration of peripheral nerves-histologic, electrophysiologic, and functional results in a rat model[J].J Trauma, 2004,56(3):571-584.
[17]Martins R S, Teodoro W R, Simplicio H,etal. Influence of suture on peripheral nerve regeneration and collagen production at the site of neurorrhaphy: an experimental study[J].Neurosurgery, 2011,68(3):765-772.
[18]Narakas A. The use of fibrin glue in repair of peripheral nerve[J].Orthop Clin North Am, 1988,19(1):187-199.
[19]Cruz N I, Debs N, Fiol R E. Evaluation of fibrin glue in rat sciatic nerve repairs[J].Plast Reconstr Surg, 1986,78(3):369-373.
[20]Liang X D, Cai H F, Hao Y Y,etal. Sciatic nerve repair using adhesive bonding and a modifid conduit[J].Neural Regeneration Research, 2014,9(6):594-601.
Effect of Medical Adhesive Braking on Severed Sciatic Nerves for Anastomosis in Rats
ZOU Xiu-qiang1, LIANG Xiang- dang1, GUO Zhan-fang1, SUN Geng2, YU Kuan-kuan1, FANG Zhuo-qun1
(1. The First Department of Osteology, General Hospital of the PLA, Beijing 100853, China; 2. Department of Osteology, 252 Hospital of the PLA, Baoding, Hebei 350025, China)
Objective To observe the effect of medical adhesive braking on severed sciatic nerves for anastomosis in rats. Methods A total of 30 male SD rats were selected and models were established, and then the rats were randomly divided into experiment group (n=15) and control group (n=15). In experiment group, the sciatic nerves were transected at the midpoint, and then were sutured for anastomosis with traditional method under operating microscope. The silica gel tubes were put over the surfaces of nerve suture sites, and the stomas sites were similar with the axial center of the tubes, and then 20 μl medical adhesive were respectively dripped on two sides of the tubes. In control group, the sciatic nerves were transected at the midpoint, and then were sutured for anastomosis with traditional method under operating microscope only. Nerval connective tissues were given general observation, indexes of nervous functions, electrophysiologic detection and histopathological observation were made in postoperative 8thweek, and the hyperplasia conditions of intraneural and extraneural connective tissues were recorded, and the number of regenerated nerve fibers in stomas were detected. Results In postoperative 8thweek, the obvious adhesions were found in nervous and surrounding tissues; the values of function indexes of left sciatic nerve (in the 6thand 8thweeks), neural latency, maximum thickness of scar connective tissue in epineurium and the total area of 4 intraneural connective tissues in experiment group were significantly lower than those in the control group (P<0.05), while the values of neural amplitude and regenerated number of nerve fibers were higher than those in the control group (P<0.05). Conclusion The medical adhesive braking on severed sciatic nerves for anastomosis in rats may inhibit the hyperplasia of scar connective tissues, and promote the regeneration of nerve fibers.
Cyanoacrylates; Braking, reconstructive; Sciatic nerve; Rats
科技部國際合作項(xiàng)目(2014DFA31230)
100853 北京,解放軍總醫(yī)院骨科一病區(qū)(鄒秀強(qiáng)、梁向黨、郭占芳、余寬寬、房卓群);071000 河北 保定,解放軍252醫(yī)院骨科(孫賡)
梁向黨,E-mail:lxd301@263.net
R-332
A
2095-140X(2015)03-0024-04
10.3969/j.issn.2095-140X.2015.03.006
2014-12-02 修回時間:2015-01-30)
*為共同第一作者