记忆合金加压钉抑制脊柱矢状面生长的实验研究

Animal experiment of memory alloy staples to control the sagittal growth of vertebrates

目的 探讨记忆合金加压钉植入后非融合性抑制胸段脊柱矢状面生长的作用.方法 将18只幼年雌性山羊随机分为长钉组、短钉组、对照组各6只.长钉组和短钉组通过前路手术在前凸的T6～11胸椎节段植入记忆加压长钉（齿长7 mm）、短钉（齿长4 mm）,对照组不予手术.分别于术前、术后3个月行X线片检查,测量Cobb角,对手术前后组间数据及组内自身对照数据进行统计学分析,并计算后凸增加率.大体观察被固定节段脊柱是否融合.结果 全部样本无脱失,均进入结果分析.T6～11 Cobb角,短钉组术前为7.0°±2.3°,术后3个月为12.7°±4.7°,后凸增加率为81.4%;长钉组术前为6.2°±4.0°,术后3个月为14.0°±4.9°,后凸增加率为125.8%;术前及术后长钉短钉两组组间比较,差异均无统计学意义（术前P=0.655;术后P=0.596）.将长钉组和短钉组分别与对照组比较,术前差异均无统计学意义（分别为P=0.929和P=0.720）;术后差异均有统计学意义（分别为P=0.007和P=0.021）.大体观察证实,植入记忆合金加压钉节段脊柱未融合.结论 在山羊胸椎正前方植入记忆合金加压钉可以非融合性控制山羊胸椎的矢状面生长,增加后凸角度.

Objective To present that Nickel-Titanium （NT） memory alloy staples in fusionlessly controlling the growth of the vertebrates in the sagittal plane. Methods Eighteen infant female goats were selected and equally divided into 3 random groups：long staple group, short staple group and blank control group. Five long staple （the legs＇ length = 7 mm） and five short staple （the legs＇ length =4 mm） were implanted into each goat in long and short staple groups repecetively by anterior approach, right on the front of the thoracic vertebrae from T6 to T11. The control group was not given any treatment. X-ray examination was performed pre-operatively and post-operatively. Cobb angle of lateral radiograph was measured and the data of Cobb angle were statistically analyzed. At the end of the experiment, whether the staples implanted spinal columns were fused or not were evaluated by gross observation. Results Finally, all of the goats were included in the final results. Before the operations, T6-11 sagittal Cobb angle was 7.0°±2.3°in short staple group, and 6.2°±4.0°in long staple group. And after the operation, the T6-11 Cobb angle was increased to 12.7°±4.7°in short staple group with the increased rate of 81.4%, and 14. 0°±4. 9° in long staple group with the increased rate of 125.8%, respectively. Before and after the surgery, there were no significant differences between long staple group and short staple group in terms of Cobb angle （ pre-operation P=0. 655, post-operation P = 0. 596）. Before the surgery, there were no differences in terms of Cobb angle,between long staple groups and control group （ P =0.929）, and short staple groups and control group（ P=0.720）. At the end of the experiment, there were significant differences between long staple group and control group in terms of Cobb angle （ P = 0. 007）, and between short staple group and control group （P=0.021）.The staples implanted spinal columns were not fused which was proved by gross observation. Conclusions The memory alloy staple implantation by anterior approach, right on the front of the thoracic vertebrae of goats, can control the growth of thoracic vertebrates leading to kyphosis.