胶原酶髓核溶解术后疼痛反应的机理——动物实验研究

Mechanism of pain response after chemonucleolysis with intradiscal injection of collagenase:Animal experimental study

目的研究胶原酶盘内注射对山羊腰椎间盘突出模型的化学髓核溶解作用,探讨化学髓核溶解术后疼痛反应的原因。方法胶原酶注射前10周,通过手术损伤椎间盘前外侧纤维环诱发椎间盘突出和退变并经MRI证实。胶原酶注射后1天、1周、2周、4周、12周观察X线片上椎间盘高度指数、椎间盘标本的组织学等变化。结果胶原酶对正常和退变椎间盘髓核组织均具有溶解作用。胶原酶在突出模型椎间盘的中央和髓核突出部位均溶解髓核组织形成空腔,对终板损伤小;而对正常椎间盘胶原酶溶解部位集中在椎间盘髓核和内层纤维环,并严重破坏终板。结论盘内注射胶原酶对椎间盘终板的破坏可能是导致化学髓核溶解术后疼痛反应的主要原因。

Objective To study the effects of intradiscal injected collagenase on a novel sheep model of intervertebral disk displacement and degeneration and speculate the reason of pain response after chemonucleolysis. Methods Sheep lumbar intervertebral disks were surgically injured, inducing disk displacement and degeneration 10 weeks before intradiscal injection of collagenase. Disk height index on radiography and histological changes were studied 1 day, 1 week, 2 weeks, 4 weeks, 12 weeks after intradiscal injection of collagenase. Results Collagenase has chemonucleolysis effects on degenerative intervertebral disks similar to normal disk tissue. Collagenase can dissolve nucleus pulposus in the center of model disks and protrusion sites simultaneously while only central portion and inner annulus fibrosus was dissolved in normal disks. Endplates in normal disks were destroyed more severe than in model disks after collagenase injection. Conclusion Collagenase can induce chemonucleolysis in model disks and dissolve nucleus pulposus in the center and protrusion sites. Endplate injuries might be the main reason for pain response after chemonucleolysis.