余成誠 郝定均黃大耿 馮航 趙松川
(西安交通大學(xué)附屬紅會(huì)醫(yī)院脊柱外科,西安710054)
人工頸椎間盤置換術(shù)并發(fā)癥的研究進(jìn)展
余成誠郝定均*黃大耿 馮航 趙松川
(西安交通大學(xué)附屬紅會(huì)醫(yī)院脊柱外科,西安710054)
近年來,人工頸椎間盤置換術(shù)(cervical disc arthroplasty,CDA)已得到廣泛應(yīng)用。隨著CDA患者的增多及隨訪時(shí)間的延長,CDA術(shù)后并發(fā)癥的報(bào)道也隨之增多。CDA的術(shù)后并發(fā)癥可以分為手術(shù)入路導(dǎo)致的并發(fā)癥、減壓導(dǎo)致的并發(fā)癥和假體相關(guān)并發(fā)癥。三者中與假體相關(guān)的并發(fā)癥是CDA所特有的并發(fā)癥,包括假體松動(dòng)及移位、假體下沉、異位骨化與自發(fā)融合、置換節(jié)段后突畸形、節(jié)段活動(dòng)度喪失。臨床醫(yī)師應(yīng)加深對這些并發(fā)癥的認(rèn)識,手術(shù)時(shí)應(yīng)小心仔細(xì),以預(yù)防并發(fā)癥的發(fā)生。
頸椎;置換術(shù);并發(fā)癥
【Key words】Cervical vertebra;Arthroplasty;Complications
近年來,人工頸椎間盤置換術(shù)(cervical disc arthroplasty,CDA)已得到廣泛應(yīng)用,至今已有6種人工頸椎間盤假體通過美國FDA認(rèn)證[1]。對于患神經(jīng)根型及脊髓型頸椎病的患者來說,CDA已被認(rèn)為可獲得相同甚至優(yōu)于傳統(tǒng)頸前路椎間盤切除減壓植骨融合術(shù)(anterior cervical discectomy and fusion,ACDF)的療效[2,3]。生物力學(xué)實(shí)驗(yàn)表明,CDA相對ACDF來說能夠保持手術(shù)頸椎節(jié)段的活動(dòng)性,從而達(dá)到緩解疼痛、改善運(yùn)動(dòng)功能、防止相鄰椎間盤代償性過度負(fù)荷及發(fā)生繼發(fā)性退行性改變的目的[4]。隨著CDA患者的增多及隨訪時(shí)間的延長,CDA術(shù)后并發(fā)癥的報(bào)道也隨之增多[5-7]。CDA術(shù)后并發(fā)癥可分為手術(shù)入路導(dǎo)致的并發(fā)癥、減壓導(dǎo)致的并發(fā)癥和假體相關(guān)并發(fā)癥[8]。
CDA采用前路手術(shù),因此手術(shù)相關(guān)的并發(fā)癥與ACDF相似,主要包括:①傷口感染,②血腫,③吞咽困難,④食管或喉損傷,⑤喉返神經(jīng)麻痹,⑥呼吸功能不全,⑦假性動(dòng)脈瘤形成,⑧椎動(dòng)脈、頸動(dòng)脈或頸靜脈撕裂,⑨Horner綜合征等[1]。術(shù)后吞咽困難是最常見的并發(fā)癥,發(fā)生率為2%~67%[9-13]。術(shù)后血腫是第二常見的并發(fā)癥,發(fā)生率為1%~11%[9-13]。各個(gè)報(bào)道的并發(fā)癥發(fā)生率相差很大,可能是因?yàn)椴l(fā)癥的鑒定標(biāo)準(zhǔn)及手術(shù)醫(yī)師的操作習(xí)慣不同所致。Goffin等[9]報(bào)道的92例單平面CDA術(shù)后患者中1例發(fā)生嚴(yán)重椎體前血腫,需要再次手術(shù)清除血腫;10例雙平面CDA術(shù)后患者中1例發(fā)生嚴(yán)重的聲音嘶啞與聲帶麻痹。Aghayev等[11]報(bào)道332例CDA術(shù)后22例出現(xiàn)聲音嘶啞與吞咽困難,1例出現(xiàn)血腫再次手術(shù)清除;隨訪中13例有聲音嘶啞與吞咽困難的表現(xiàn),其中12例在2年的隨訪時(shí)間內(nèi)恢復(fù)正常,1例3年隨訪仍未恢復(fù)。一項(xiàng)對1820例CDA患者的調(diào)查研究顯示術(shù)后感染率為2.2%,血腫發(fā)生率為2.2%,吞咽困難發(fā)生率為19.2%[13]。
臨床醫(yī)師應(yīng)該提高對CDA術(shù)后并發(fā)癥的認(rèn)識,在手術(shù)過程中加以小心,注意動(dòng)作的輕柔,減少對細(xì)小解剖結(jié)構(gòu)的破壞,術(shù)后早期識別并及時(shí)處理并發(fā)癥。
減壓不當(dāng)可能會(huì)導(dǎo)致神經(jīng)壓迫引起的癥狀緩解不徹底、不緩解甚至加重,腦脊液漏等。神經(jīng)癥狀加重在CDA術(shù)后較罕見,通常是由椎間孔處的神經(jīng)根減壓不充分導(dǎo)致,由于椎間孔處操作不當(dāng)而引起的神經(jīng)根損傷者多見,神經(jīng)根壓迫損傷可能導(dǎo)致患者出現(xiàn)根性疼痛、肢體感覺運(yùn)動(dòng)異常等,可以在術(shù)后行保守治療[6]。Goffin等[9]報(bào)道的102例CDA術(shù)后患者中10例有感覺遲鈍及感覺異常,4例在手術(shù)后原本手術(shù)節(jié)段仍然有持續(xù)不緩解的神經(jīng)壓迫癥狀,4例出現(xiàn)了其它節(jié)段的神經(jīng)癥狀。一項(xiàng)對229例CDA術(shù)后患者進(jìn)行的隨訪研究發(fā)現(xiàn)4例出現(xiàn)腦脊液漏[14]。一項(xiàng)對1820例CDA患者的調(diào)查研究顯示術(shù)后有0.5%的患者出現(xiàn)腦脊液漏,1.6%的患者出現(xiàn)神經(jīng)并發(fā)癥[13]。
CDA除了對椎管進(jìn)行充分減壓之外,還需要注意對椎間孔進(jìn)行充分減壓,以防治神經(jīng)癥狀的加重,同時(shí)行減壓操作時(shí)需小心謹(jǐn)慎,以防止出現(xiàn)腦脊液漏。
與人工頸椎間盤假體有關(guān)的并發(fā)癥主要有:①假體松動(dòng)及移位,②假體下沉,③異位骨化與自發(fā)融合,④置換節(jié)段后凸畸形,⑤節(jié)段活動(dòng)度喪失等[1,15,16]。
3.1假體松動(dòng)及移位
人工椎間盤通過對椎體終板的研磨使假體與椎體的形狀達(dá)到契合,從而植入假體,有些會(huì)輔以螺釘?shù)确绞焦潭ǎ话銇砘蚓商峁┝己玫那昂蠓胶蛡?cè)方的及時(shí)穩(wěn)定性。很多學(xué)者報(bào)道了術(shù)后及隨訪的假體松動(dòng)及移位,導(dǎo)致手術(shù)失敗及需要再次手術(shù),但有些隨訪發(fā)現(xiàn)的假體移位沒有任何癥狀[9-11,17,18]。Zhang等[18]發(fā)現(xiàn)66例CDA術(shù)后患者在隨訪中2例出現(xiàn)假體移位,但是沒有任何癥狀,未予特殊治療。Pickett等[10]報(bào)道了74例行椎間盤置換術(shù)患者中1例出現(xiàn)術(shù)后假體移位。Aghayev等[11]報(bào)道332例CDA患者中1例在術(shù)后出現(xiàn)假體位移需要再次手術(shù)治療。總體來說假體松動(dòng)及移位的發(fā)生率不高,但各學(xué)者報(bào)道的發(fā)生率相差較大。
假體發(fā)生松動(dòng)及移位的主要原因包括[16,19]:①術(shù)者對終板的打磨處理不當(dāng)導(dǎo)致假體與骨界面吻合不當(dāng);②選擇的假體大小不適;③生物因素如骨質(zhì)增長慢、終板重吸收等導(dǎo)致假體植入后穩(wěn)定性變差;④頸椎關(guān)節(jié)置換后可能會(huì)遺留碎屑,這些碎屑可能會(huì)引起局部的炎癥,從而導(dǎo)致疼痛、骨溶解和假體的松動(dòng)。需要注意的是患者有骨質(zhì)疏松或代謝性骨疾病時(shí),由于椎體骨密度降低,不能有效支撐及固定假體,假體松動(dòng)移位及下沉幾乎是不可避免的,因此骨質(zhì)疏松和骨代謝疾病是CDA的禁忌證。
3.2假體下沉
假體下沉是指下沉的人工頸椎間盤進(jìn)入研磨過的椎體終板。假體下沉?xí)?dǎo)致置換關(guān)節(jié)活動(dòng)度的減小,使相鄰的椎間盤活動(dòng)負(fù)荷增加,加速相鄰椎間盤的退變。隨著CDA的廣泛應(yīng)用,假體下沉也逐漸引起骨科醫(yī)師的關(guān)注,若假體的大小與椎體不契合(尤其是假體過?。苋菀壮霈F(xiàn)假體下沉[20]。一項(xiàng)體外生物力學(xué)實(shí)驗(yàn)表明,假體與錐體的吻合面積過小會(huì)使軸向應(yīng)力增大,從而增加假體下沉的發(fā)生率[21]。假體下沉的發(fā)生率較少,Zigle等[22]對103例ProDisc-C人工頸椎間盤的CDA患者進(jìn)行了5年隨訪,僅發(fā)現(xiàn)1例出現(xiàn)假體下沉。
假體下沉主要原因及程度[19]:①假體與椎體吻合面積過小導(dǎo)致接觸面壓強(qiáng)過大,理論上講,假體與上下椎體的吻合面積應(yīng)達(dá)到100%;②終板的處理不當(dāng),不能與假體契合或骨性終板切除過多導(dǎo)致椎體難以支撐假體,不同的假體對處理終板有不同要求,終板軟骨應(yīng)完全刮掉,但骨性終板不宜切除過多,達(dá)到與假體接觸面形狀契合即可;③現(xiàn)有的人工頸椎間盤假體都需要將椎體與假體的吻合面打磨成接近水平的形狀,與椎骨及椎間盤的正常解剖學(xué)結(jié)構(gòu)不符,加重了軸向應(yīng)力,可以設(shè)計(jì)一種與解剖學(xué)結(jié)構(gòu)相差不大的新型假體,以減小頸椎軸向應(yīng)力;④患者有骨質(zhì)疏松癥,椎體骨難以支撐假體,容易出現(xiàn)假體下沉[15],因此骨質(zhì)疏松癥患者為頸椎間盤置換術(shù)的禁忌證。
3.3異位骨化與自發(fā)融合
異位骨化是指正常情況下無骨組織的組織內(nèi)形成了骨組織。異位骨化與自發(fā)融合在CDA術(shù)后發(fā)生較多,隨著CDA研究的深入和認(rèn)識的加深,異位骨化的相關(guān)報(bào)道也隨之增多,但是各個(gè)研究的發(fā)生率相差較大,至今仍未找到異位骨化的原因[23,24]。Leung等[43]報(bào)道CDA術(shù)后1年異位骨化的發(fā)生率為17.8%,而Lee等[24]報(bào)道術(shù)后1年異位骨化的發(fā)生率高達(dá)62.5%。Chen等[25]經(jīng)過meta分析發(fā)現(xiàn)國外人群CDA術(shù)后12個(gè)月內(nèi)異位骨化的平均發(fā)生率為44.6%,24個(gè)月內(nèi)異位骨化的平均發(fā)生率為58.2%。田偉等[26]經(jīng)過meta分析發(fā)現(xiàn)中國大陸人群CDA術(shù)后12個(gè)月異位骨化的平均發(fā)生率為3.3%,24個(gè)月內(nèi)異位骨化的平均發(fā)生率為6.2%。國內(nèi)外相差很大,這可能是因?yàn)閲鴥?nèi)外醫(yī)師對影像學(xué)資料解讀不同以及我國骨科醫(yī)師對一些有異位骨化高危因素的患者比較謹(jǐn)慎。異位骨化可能發(fā)展成手術(shù)節(jié)段的自發(fā)融合,自發(fā)融合會(huì)造成節(jié)段活動(dòng)度喪失[27]。郝定均等[16]對融合的定義為患者X線片提示ROM<4°,有骨小梁在兩個(gè)椎體間連接,骨表面的透亮區(qū)不超過50% Pickett等[10]報(bào)道74例CDA術(shù)后患者中2例發(fā)生了異位骨化和自發(fā)融合。Oh等[12]對60例CDA術(shù)后患者進(jìn)行了12個(gè)月的隨訪,其中2例出現(xiàn)自發(fā)融合。據(jù)報(bào)道,性別為男性與年齡增加是異位骨化的危險(xiǎn)因素[28],而預(yù)防性非甾體類消炎藥(NSAIDs)能夠減少異位骨化的發(fā)生[29]。但Lee等[24]研究發(fā)現(xiàn)性別、年齡是否使用NSAIDs與是否發(fā)生異位骨化無相關(guān)性。
為了預(yù)防CDA術(shù)后異位骨化及自發(fā)融合,應(yīng)該做到以下幾點(diǎn):①嚴(yán)格把握手術(shù)指征及禁忌證,當(dāng)病變節(jié)段椎間隙高度小于相鄰節(jié)段正常椎間隙的80%時(shí)不適合手術(shù)[23];②選擇合適大小的假體,使假體與椎體關(guān)節(jié)面充分吻合并保持足夠的椎間隙高度③手術(shù)時(shí)注意動(dòng)作輕柔,避免造成頸部肌肉的拉傷引起炎癥反應(yīng);④徹底沖洗減壓研磨時(shí)產(chǎn)生的骨屑⑤術(shù)后常規(guī)應(yīng)用2周NSAIDs。
3.4置換節(jié)段后凸畸形
CDA術(shù)后可能喪失頸椎生理性前凸而發(fā)生頸椎后凸,這通常是因?yàn)閷κ中g(shù)節(jié)段的終板處理不當(dāng),影響了人工椎間盤置入的角度,術(shù)前伴有頸椎后凸時(shí)增加了術(shù)后易患頸椎后凸的危險(xiǎn)性,因此頸椎后凸傳統(tǒng)上被認(rèn)為是CDA的禁忌證之一[30]。但近年來的研究認(rèn)為術(shù)前頸椎后凸不是頸椎間盤置換的禁忌證[31]。置換節(jié)段后凸畸形會(huì)加速鄰近節(jié)段椎間盤的退變。Pickett等[32]指出置換節(jié)段后凸畸形的形成與植入假體時(shí)的角度有密切關(guān)系;Shim等[33]研究認(rèn)為置換節(jié)段后凸畸形的形成與假體的設(shè)計(jì)及是否切除后縱韌帶有關(guān);Hacker等[34]認(rèn)為為了防止置換節(jié)段后突畸形,手術(shù)時(shí)應(yīng)該始終保持頸椎中立位,并使假體與椎體密切吻合。
為了防止CDA術(shù)后置換關(guān)節(jié)后凸畸形應(yīng)該進(jìn)行如下處理:①手術(shù)時(shí)保持患者頸椎呈中立位;②仔細(xì)研磨椎體終板,保證假體與椎體緊密吻合;③植入假體時(shí)使假體與椎間隙角度平行。
3.5節(jié)段活動(dòng)度喪失
節(jié)段活動(dòng)度喪失主要由異位骨化、自發(fā)融合及置換節(jié)段的后凸畸形導(dǎo)致,假體下沉也會(huì)造成節(jié)段活動(dòng)度的丟失。在進(jìn)行手術(shù)時(shí)按上述方法嚴(yán)格預(yù)防異位骨化、自發(fā)融合、后凸畸形、假體下沉,節(jié)段活動(dòng)度喪失的可能性會(huì)大大降低。
綜上,CDA的術(shù)后并發(fā)癥可分為手術(shù)入路導(dǎo)致的并發(fā)癥、減壓導(dǎo)致的并發(fā)癥及假體相關(guān)并發(fā)癥。手術(shù)入路導(dǎo)致的并發(fā)癥發(fā)生率較高,常見有吞咽困難、血腫、傷口感染等;減壓不當(dāng)可能會(huì)導(dǎo)致神經(jīng)癥狀及腦脊液漏等并發(fā)癥;假體相關(guān)并發(fā)癥主要包括假體松動(dòng)及移位、假體下沉、異位骨化與自發(fā)融合、置換節(jié)段后凸畸形、節(jié)段活動(dòng)度喪失等。有些并發(fā)癥的發(fā)生機(jī)制尚不明確,臨床醫(yī)師應(yīng)加深對這些并發(fā)癥的認(rèn)識,手術(shù)時(shí)應(yīng)小心仔細(xì),以預(yù)防并發(fā)癥的發(fā)生。另外,設(shè)計(jì)更為合理的人工頸椎間盤對預(yù)防假體相關(guān)并發(fā)癥具有重要意義。
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Research progress on complications of cervical disc arthroplasty
YU Chengcheng,HAO Dingjun*,HUANG Dageng,F(xiàn)ENG Hang,ZHAO Songchuan
(Department of Spine Surgery,Honghui Hospital,Xi'an Jiao tong University,Xi'an 710054,China)
】Cervical disc arthroplasty(CDA)has been used widely in these years.With increasing patients and longer follow-up,more complications have been reported.Major complications of CDA results from operative approach,decompression and prosthesis.Among these,the complications related to the prosthesis are characteristic of CDA,including prosthesis loosening and migration,subsidence,heterotopic ossification,kyphotic,losing of the physiological motion function.Clinicians should know these complications deeply and be careful in surgery.
2095-9958(2016)08-0347-04
10.3969/j.issn.2095-9958.2016.04-17
郝定均,E-mail:haodingjun@126.com