Department of Orthopaedic Surgery, Tohoku University School of Medicine, Sendai, Japan.
Kurihara Central Hospital, Kurihara, Japan.
Arthroscopy. 2018 Feb;34(2):377-385. doi: 10.1016/j.arthro.2017.07.022. Epub 2017 Oct 5.
To investigate the minimum distance between the anchors without decreasing the pullout strength using the polyurethane foams and the porcine bones.
Metal screw-type anchors and PEEK (polyether ether ketone) coil-type anchors were used. Two same-type suture anchors were placed into the polyurethane foams and porcine bones. The polyurethane foams were 3 different densities simulating severe osteoporosis, osteoporosis, and normal bone. The distances between the centers of anchors were set at 4, 6, 8, and 10 mm. The pair of anchors were loaded to failure if they had not been pulled out after cyclic loading from 50 to 200 N, 10 cycles per each 50-N increment. Mode of failure, ultimate load to failure, displacement of the anchor, and number of cycles completed were recorded.
In all polyurethane foams of 3 different densities with use of metal screw-type anchors, the 4-mm group demonstrated a significantly lower ultimate load to failure compared with the 6-, 8-, and 10-mm groups (P < .01). There were no significant differences in the load to failure among the 6-, 8-, and 10-mm groups. Porcine bone or PEEK coil-type anchor showed results similar to those of the metal screw-type anchors.
For the 2 tested anchors, the minimum distance between the anchors without decreasing the pullout strength was 6 mm (center to center) regardless of bone density in a biomechanical study.
Although it has been thought that the minimum distance between the anchors without decreasing the pullout strength was 1 cm (center to center), our data showed that it was 6 mm.
使用聚氨酯泡沫和猪骨来研究不降低拔出强度的情况下锚钉之间的最小距离。
使用金属螺钉型锚钉和 PEEK（聚醚醚酮）线圈型锚钉。将两个相同类型的缝合锚钉放置在聚氨酯泡沫和猪骨中。聚氨酯泡沫模拟严重骨质疏松、骨质疏松和正常骨三种不同密度。锚钉中心之间的距离设定为 4、6、8 和 10 mm。如果在从 50 到 200 N、每 50 N 增加 10 次循环加载后，锚钉没有被拔出，则对这对锚钉进行加载直至失效。记录失效模式、最终拔出载荷、锚钉位移和完成的循环次数。
在使用金属螺钉型锚钉的所有三种不同密度的聚氨酯泡沫中，4 mm 组的最终拔出载荷明显低于 6、8 和 10 mm 组（P <.01）。6、8 和 10 mm 组之间的拔出载荷无显著差异。猪骨或 PEEK 线圈型锚钉的结果与金属螺钉型锚钉相似。
在这项生物力学研究中，对于这两种测试的锚钉，无论骨密度如何，不降低拔出强度的情况下，锚钉之间的最小距离为 6 mm（中心到中心）。
虽然人们一直认为不降低拔出强度的情况下锚钉之间的最小距离为 1 cm（中心到中心），但我们的数据表明最小距离为 6 mm。
