椎间盘移植的实验研究

本实验研究目的在于：（１）建立间盘移植动物模型，（２）观察椎间盘移植术后不同时期Ｘ线、组织病理学、生物化学和生物力学变化。于１５只猴体上制备自体腰椎间盘移植模型，另有３只猴作为正常生物力学对照。结果表明移植间盘高度术后１～３个月呈下降趋势，４～１２个月呈恢复上升趋势。光镜下纤维环和终板软骨结构无明显改变，髓核中有部分细胞退变，同时亦有成软骨样纤维细胞的再生。术后２～４个月蛋白多糖和含水量呈下降趋势，６～１２个月有恢复；胶原含量２～６个月增加幅度较大，６～１２个月较平缓，其中髓核较纤维环明显。生物力学结果表明术后２个月时移植间盘活动度增大，术后４～１２个月恢复至正常水平。实验结果表明移植间盘在组织病理及生物化学方面有轻度退变倾向，同时又有一定的自我修复能力，生物力学上可满足生理活动功能需要。

IntervertebralDiscAutograftingRuanDike

Thepurposeofthisstudyistoexplorethepossibilityofdisctransplantationby(1)es-tablishingananimalmodelfordiscgrafting,(2)studyingtheradiological,pathological,biochemicalandbiomechanicalchangesinafreshdiscautograft.Fifteenrhesusmonkeysweredividedinto4groups.Undergeneralanaesthesia,througharetroperitonealapproach,osteotomieswereperformedattheend-platesabout2.0mmawayfromtheL3-4intervertebraldisc.Afterenblocmobilizationofthecompositegraft,itwasrepositionedandanchoredwithsuture.4groupsofanimalsweresacrificedafter2,4,6and12monthsrespectively.TwocompletelumbarspinespecimenincludingL1tosacrumfromeachgroupwereexaminedbiomechanicalyonaspinalmotiontestapparatususingamotionanalysissystem(Elite).Threecompletelumbarspinespecimensfromthreenormalmonkeyswereusedasbiomechani-calcontrols.Theremainingtwodiscspecimensfromeachgroupweretestedforwatercontent(Swine),hydroxyprolinecontent(Herbert)andproteoglycancontent(Pearce).Theresultswereanalyzedstatis-ticalywitht-test.ThediscswerealsoexaminedhistochemicalyandunderTEM.Alanimalssur-vivedthesurgicalprocedure.Atonemonthaftersurgery,alosteotomieshadhealedradiologicaly.Ra-diographalsodemonstratedgraduallossofintervertebraldischeightinthefirstthreemonthspostoper-atively,thentherewasareversionofthedischeightfrom4to12monthspostoperatively.Therewasadecreaseofproteoglycanandwatercontentat2and4months,butproteoglycanwasreversedat6and12months.Therewasaconstantincreaseinthehydroxyprolinecontentoverthefolow-upperiod.Histologicaly,indiscspecimensfromalstages,endplatechondrocyteswereseentobeviable,therewasnoevidenceofcracksorfracturesoftheannulusandviablenotochordalcelswerefoundinthenu-cleuspulposus.Biomechanicaly,hypermobilityoftheoperatedsegmentwasseenat2months,thenthehypermobilitywasdecreasednearlytonormallevelat6and12months.Thesurgicaltechniqueusedemphasizedtheimportanceofharvestingacompleteintactdiscandclearingaldiscmaterialefectingondiscmetabolism.Thereversionofproteoglycancontentat6and12months,conbinedwithreversionofdischeightandbiomechanicalstabilityat6and12months,indicatedthatthefunctionaloutcomeofsuchdiscgraftingissatisfactory.Meanwhile,theencoruagingfindingsofgoodsurvivalofthechondrocytesandthenotochordalcelsindicatedthattheycouldstandtheshortperiodofischaemiabe-forehealingandrevascularzationofthebonyendplatestookplace.