Sawasdipong Arun, Sudnongbua Rattasat
Department of Orthopaedic, Phramongkutklao Hospital, Bangkok, Thailand.
J Med Assoc Thai. 2009 Dec;92 Suppl 6:S221-5.
Rotational Malalignment is abnormal rotational alignment between proximal and distal parts of femoral bone. If there is more than 15 degrees of rotational malalignment in femoral bone, the patient will have abnormality of gait and they will have difficulties to perform their daily life activities. The chances to have rotational malalignment in femoral fracture are increased after intramedullary nailing which is more than plate and screws fixation. In this study, we used contralateral Lesser Trochanter to be the reference for rotational determiner.
17 pairs of never-broken cadeveric femur in the same person were randomly sampling and then measured the anteversion of both cadeveric femurs. Lessor trochanter of normal leg was measured to be as the landmark. The rotational malalignment was determined based on the differences between the starting angle and measured angle. Repeated measurements were done by the same investigators, other staffs, residents, and medical students to examine the precision.
There was no statistically significance of both bone sides reported by intra-inter examiners (p-value = 0.904). However, we found high correlation for rotational malalignment in all 3 intra-examiners (p-value < 0.0001), and the intraclass-correlation coefficient was 0.919 (0.819-0.968). Moreover, there was also a good correlation in all 3 Inter-examiners; statistically significant (p-value = 0.009), and ICC was 0.726 (0.198-0.926).
Our finding confirmed that the accuracy of contralateral lessor trochanter which was used to be a landmark for prevention of rotational malalignment in fracture of femoral shaft was highly reliable.
旋转对线不良是股骨近端与远端之间的异常旋转对线。如果股骨旋转对线不良超过15度,患者会出现步态异常,日常生活活动也会有困难。与钢板螺钉固定相比,髓内钉固定后股骨骨折发生旋转对线不良的几率增加。在本研究中,我们使用对侧小转子作为旋转测定的参考。
对同一人17对未骨折的尸体股骨进行随机抽样,然后测量双侧尸体股骨的前倾角。以正常腿的小转子作为测量标志。根据起始角度与测量角度的差异确定旋转对线不良。由同一研究者、其他工作人员、住院医师和医学生进行重复测量以检验其精确性。
检查者内双侧股骨无统计学意义(p值 = 0.904)。然而,我们发现所有3名检查者内旋转对线不良的相关性都很高(p值 < 0.0001),组内相关系数为0.919(0.819 - 0.968)。此外,所有3名检查者间也有良好的相关性;具有统计学意义(p值 = 0.009),组内相关系数为0.726(0.198 - 0.926)。
我们的研究结果证实,对侧小转子作为股骨干骨折旋转对线不良预防的标志,其准确性高度可靠。