Department of Orthopaedic Surgery, Taipei City Hospital, Taipei, Taiwan.
Spine (Phila Pa 1976). 2011 May 1;36(10):761-9. doi: 10.1097/BRS.0b013e3181e08f01.
In vitro and in vivo studies to assess the effect of direct anular repair on subsequent degeneration of intervertebral discs (IVDs).
To assess whether a new suturing method could provide sealing effect on IVD after discectomy, and influence degenerative process of IVD.
Recurrent disc herniation and subsequent disc degeneration are major problems after discectomy. Anular repair can reduce the risk of recurrence, but its effect on disc degeneration needs more investigation.
A new suturing technique, the modified purse-string suture (MPSS), was designed for direct closure of anular incision. Intact motion segments of porcine lumbar spine were used to validate this technique in resisting disc pressure under mechanical loadings. A transverse slit incision was made in the anterior anulus of porcine cervical discs, with or without sealing of the anular defect by this suturing method. Magnetic resonance imaging grading was recorded before and after surgery. Anular healing was assessed histologically and gene expression of aggrecan, collagen type I, II, and matrix metalloproteinase-13 in nucleus pulposus were investigated.
The average failure force of axial compression was 1150.3 ± 121.1 N for a simple suture, and 2917.9 ± 627.6 N for a MPSS. Cyclic loading test showed that the repaired discs succeeded against repeated compression forces. Magnetic resonance imaging and gross appearances showed lesser degenerative changes in repaired discs than in injured discs at each time period. In repaired discs, mRNA expression of aggrecan and type II collagen downregulated slightly with time, whereas it decreased rapidly and persistently in unrepaired discs. Histologic findings showed primary healing of outer anular tract in repaired discs.
In this pilot study, the MPSS can provide effectively sealing for damaged anulus to withstand stresses. Direct repair of anular incision by this suturing method does significantly slow down degenerative process within discs after discectomy.
体外和体内研究评估直接环修复对椎间盘（IVD）后续退变的影响。
评估一种新的缝合方法在椎间盘切除术后是否能对 IVD 提供密封效果，并影响 IVD 的退行性过程。
椎间盘突出症复发和随后的椎间盘退变为椎间盘切除术后的主要问题。环修复可以降低复发的风险，但对椎间盘退变的影响需要更多的研究。
设计了一种新的缝合技术，改良荷包缝合（MPSS），用于直接闭合环切口。使用完整的猪腰椎运动节段，在机械载荷下验证该技术抵抗椎间盘压力的能力。在前环上做一个横向的裂缝切口，用或不用这种缝合方法封闭环缺陷。手术前后记录磁共振成像分级。组织学评估环愈合情况，研究核髓中聚集蛋白、胶原 I、II 和基质金属蛋白酶-13 的基因表达。
单纯缝合的轴向压缩平均失效力为 1150.3±121.1N，改良荷包缝合为 2917.9±627.6N。循环加载试验表明，修复后的椎间盘能够承受反复的压缩力。磁共振成像和大体外观显示，在每个时间段，修复后的椎间盘的退行性变化都小于受伤的椎间盘。在修复的椎间盘，随着时间的推移，聚集蛋白和 II 型胶原的 mRNA 表达略有下调，而在未修复的椎间盘，其表达迅速且持续下降。组织学发现修复后的椎间盘外环道有初步愈合。
在这项初步研究中，改良荷包缝合可以有效地密封受损的环以承受应力。通过这种缝合方法直接修复环切口可以显著减缓椎间盘切除术后椎间盘的退行性过程。
