超声引导针刀松解椎间孔内口对兔软骨终板基质稳态的影响

Effect of ultrasound-guided needle-knife on matrix homeostasis of rabbit cartilaginous endplate

背景:软骨终板基质稳态与椎间盘退变关系密切,针刀松解椎间孔内口后壁黄韧带可改善腰椎间盘退变患者的症状,其作用机制是否与调控软骨终板基质稳态有关尚待明确。目的:探讨超声引导下针刀松解兔L_(7)/S_(1)椎间孔内口对软骨终板基质稳态的影响。方法:24只雄性新西兰兔随机分为对照组6只、造模组18只,采用横断棘上棘间韧带后间歇性站立的方式进行腰椎间盘退变造模,时间为12周。造模后将造模组随机分为模型组、针刀组、假针刀组,每组6只。针刀组在超声引导下针刀松解兔L_(7)/S_(1)右侧椎间孔内口后壁黄韧带,假针刀组针刀只抵达椎间孔内口后壁黄韧带表面,共干预4次,每次间隔1周;对照组、模型组兔不做干预。干预结束30 d后,MRI观察椎间盘退变情况;苏木精-伊红染色、番红O固绿染色观察L_(7)/S_(1)椎间盘软骨终板、髓核、纤维环形态并评分;免疫组化检测L_(7)/S_(1)椎间盘髓核、软骨终板Ⅱ型胶原、蛋白聚糖、基质金属蛋白酶13表达。结果与结论:①MRI显示,L_(7)/S_(1)髓核相对灰度值模型组明显低于对照组(P<0.01),针刀组高于模型组和假针刀组(P<0.05);②苏木精-伊红染色及番红O固绿染色显示,模型组髓核、纤维环退变明显,软骨终板变薄,与骨性终板交界处钙化明显,针刀组软骨终板形态及髓核退变较模型组改善;模型组、针刀组、假针刀组形态学评分明显高于对照组(P<0.01);针刀组评分明显低于模型组和假针刀组(P<0.01);③免疫组化显示,与对照组比较,模型组和假针刀组髓核、软骨终板中Ⅱ型胶原、蛋白聚糖表达明显降低(P<0.01),基质金属蛋白酶13表达明显升高(P<0.01);与模型组、假针刀组比较,针刀组髓核、软骨终板Ⅱ型胶原、蛋白聚糖表达升高(P<0.05),基质金属蛋白酶13表达明显降低(P<0.01);④结论:针刀松解椎间孔内口可调节兔软骨终板基质稳态,改善椎间盘退变。

BACKGROUND:Cartilaginous endplate stromal homeostasis is closely related to intervertebral disc degeneration.Acupotomy that releases posterior wall ligamentum flavum of the interforaminal orifice can improve the symptoms of patients with lumbar disc degeneration.Whether the mechanism of action is related to the regulation of cartilaginous endplate stromal homeostasis remains to be clarified.OBJECTIVE:To investigate the effect of ultrasound-guided needle-knife relaxation of the internal orifice of the rabbit L7/S1 intervertebral foramina on the matrix homeostasis of the rabbit cartilage endplate.METHODS:A total of 24 male New Zealand rabbits were randomly divided into a control group(n=6)and a modeling group(n=18).Lumbar disc degeneration modeling was performed by intermittent standing after transection of the supraspinous interspinous ligament for 12 weeks.After modeling,the modeling group was randomly divided into model group,needle-knife group and fake needle knife group,with 6 rabbits in each group.In the needle-knife group,the ultrasound-guided needle-knife released the ligamentum flavum posterior wall of the right intervertebral foramina,while in the fake needle-knife group,the needle-knife only reached the surface of the posterior wall ligamentum flavum of the intervertebral foramina,with a total of four interventions,each time at an interval of 1 week.No intervention was performed in the control and model groups.Thirty days after the intervention,the disc degeneration was observed by MRI.The morphology of L7/S1 intervertebral disc cartilaginous endplate,nucleus pulposus and annulus fibrosus were observed with hematoxylin-eosin and safranin O-fast green staining and was then scored.The expressions of type II collagen,proteoglycan and matrix metalloproteinase-13 in nucleus pulposus and cartilage endplate of L7/S1 intervertebral disc were detected by immunohistochemistry.RESULTS AND CONCLUSION:MRI results showed that the relative gray value of L7/S1 nucleus pulposus was significantly lower in the model group than in the control group(P<0.01),and higher in the needle-knife group than in the model group and the fake needle-knife group(P<0.05).Hematoxylin-eosin and safranin O-fast green staining showed obvious degeneration of the nucleus pulposus and annulus fibrosus,thinning of the cartilaginous endplate,and obvious calcification at the junction with bone endplate in the model group.The morphology of the cartilaginous endplate and degeneration of the nucleus pulposus were improved in the needle-knife group compared with the model group.The morphological scores of the model group,needle-knife group and fake needle-knife group were significantly higher than those of control group(P<0.01).The morphological score of the needle-knife group was significantly lower than that of the model group and fake needle-knife group(P<0.01).Immunohistochemistry results showed that compared with the control group,the expressions of type II collagen and Aggrecan in the nucleus pulposus and cartilage endplate in the model group and fake needle-knife group were significantly decreased(P<0.01),while the expression of matrix metalloproteinase-13 was significantly increased(P<0.01).Compared with the model group and fake needle-knife group,the expressions of type II collagen and Aggrecan in the nucleus pulposus and cartilage endplate were increased in the needle-knife group(P<0.05),while the expression of matrix metalloproteinase-13 was decreased significantly(P<0.01).In conclusion,the relaxation of the interforaminal orifice by needle knife can regulate the matrix homeostasis of the rabbit cartilage endplate and improve the degeneration of the intervertebral disc.