Caja Víctor L, Piză Gabriel, Navarro Antonio
Hospital Universitari Germans Trias I Pujol, Badalona, Barcelona, Spain.
J Bone Joint Surg Am. 2003 Aug;85(8):1527-31. doi: 10.2106/00004623-200308000-00014.
Tibial valgus, a known complication of leg lengthening with external fixation techniques, has been related to the stability of the bone-fixator system and, in particular, to pin loosening. A hydroxyapatite coating has been reported to enhance the quality of the bone-pin interface. The aim of this study was to compare the prevalence of axial deformity after tibial lengthening with hydroxyapatite-coated external fixation pins with the prevalence after tibial lengthening with uncoated pins.
We conducted a prospective study of thirty-four symmetrical tibial lengthening procedures in seventeen pathologically short patients. One limb of each patient was lengthened with use of hydroxyapatite-coated pins and the other, with standard uncoated pins; the sides of the operations were randomly selected. The bone angle in the frontal plane was measured before the operation and at the end of the fixation period, and the difference between these measurements was compared between the lengthening procedures performed with coated pins and those performed with uncoated pins.
The mean valgus deviation of the tibia was 6.5 degrees in the group treated with hydroxyapatite-coated pins and 12.5 degrees in the group treated with uncoated pins (p = 0.023). With the numbers available, other factors previously related to the development of valgus deformity did not differ significantly between the two groups.
Tibiae that are lengthened with the use of hydroxyapatite-coated external fixation pins are less prone to axial deviation in the frontal plane than are those treated with uncoated pins.
Therapeutic study, Level I-1a (randomized controlled trial [significant difference]). See Instructions to Authors for a complete description of levels of evidence.
胫骨外翻是外固定技术进行肢体延长时已知的一种并发症，与骨-固定器系统的稳定性有关，尤其是与钢针松动有关。据报道，羟基磷灰石涂层可提高骨-钢针界面的质量。本研究的目的是比较使用羟基磷灰石涂层外固定钢针进行胫骨延长后与使用未涂层钢针进行胫骨延长后轴向畸形的发生率。
我们对17例病理性短腿患者的34例双侧胫骨延长手术进行了一项前瞻性研究。每位患者的一侧肢体使用羟基磷灰石涂层钢针进行延长，另一侧使用标准未涂层钢针进行延长；手术侧别随机选择。在手术前和固定期结束时测量额状面的骨角度，并比较使用涂层钢针和未涂层钢针进行延长手术的测量值之间的差异。
使用羟基磷灰石涂层钢针治疗的组胫骨平均外翻角度为6.5度，使用未涂层钢针治疗的组为12.5度（p = 0.023）。就现有数据而言，先前与外翻畸形发生相关的其他因素在两组之间无显著差异。
与使用未涂层钢针治疗的胫骨相比，使用羟基磷灰石涂层外固定钢针延长的胫骨在额状面更不易发生轴向偏差。
治疗性研究，I-1a级（随机对照试验[有显著差异]）。有关证据水平的完整描述，请参见《作者须知》。
