The tunnel disappears after the screw is absorbed, avoiding the ligament's bump toward the inside tunnel, which leads to gradual extension of the inside tunnel and cause the ligament flabby.
隧道内口可吸收螺钉挤压固定，愈合后内口消失，可避免韧带撞击内口使之逐渐扩大引起重建韧带松弛。
2
Conclusion. With extension of instrumentation across the lumbosacral junction, our results indicate significant improvement in stability with the use of S1 screws and iliac screw fixation.
结论随着腰骶关节固定器械的扩展，我们的结果表明使用S1螺钉和髂螺钉固定使得固定稳定性显著提高。
3
There may be two reasons in relation to vibration:(1) No grid connection with long screw bolt at the flanges of at two ends of extension joint;