Kohn D, Rose C
Orthopaedic Hospital, Hannover Medical School, Germany.
Am J Sports Med. 1994 May-Jun;22(3):334-8. doi: 10.1177/036354659402200307.
Interference screw fixation is frequently used in anterior cruciate ligament reconstruction with the bone-patellar tendon-bone graft. There have been no data available about the influence of screw diameter and insertion torque on primary stability. We designed a cadaveric study using paired knees to analyze the comparative effectiveness of 20-mm long screws of different diameters (9 mm versus 7 mm) and the significance of torque during screw insertion. Testing to failure was performed in a tensiometer with a crosshead speed of 200 mm/min. After slippage of a bone peg in the 7-mm screw specimens, the experiment was repeated in each specimen with a 9-mm screw fixation. Maximum tensile force was greater at the femoral insertion than at the tibial site. Results of refixations with 9-mm screws were only slightly inferior to the original 9-mm screw fixation specimens. Our results further showed that the torque can be used as a predictor of the stability of the bone block but cannot be used as an indicator for the strength of the reconstruction. The 7-mm screws are not recommended for tibial fixation. Failed 7-mm screw fixations can be replaced by 9-mm screws and refixations were successful in our study model.
在使用骨-髌腱-骨移植物进行前交叉韧带重建时，经常采用干涉螺钉固定。目前尚无关于螺钉直径和插入扭矩对初始稳定性影响的数据。我们设计了一项尸体研究，使用配对膝关节来分析不同直径（9毫米与7毫米）的20毫米长螺钉的比较效果以及螺钉插入过程中扭矩的意义。在十字头速度为200毫米/分钟的拉力试验机上进行直至失效的测试。在7毫米螺钉标本中的骨栓出现滑动后，对每个标本用9毫米螺钉固定重复实验。股骨插入处的最大拉力大于胫骨部位。用9毫米螺钉重新固定的结果仅略逊于原始9毫米螺钉固定标本。我们的结果进一步表明，扭矩可用作骨块稳定性的预测指标，但不能用作重建强度的指标。不建议将7毫米螺钉用于胫骨固定。在我们的研究模型中，失败的7毫米螺钉固定可用9毫米螺钉替换并成功重新固定。
