Precision of using contralateral lesser trochanter as a landmark to prevent rotational malalignment in fracture shaft of femur: a human cadaveric study.

BACKGROUND: 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.

MATERIAL AND METHOD: 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.

RESULTS: 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).

CONCLUSION: 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.