Intraoperative control of axes, rotation and length in femoral and tibial fractures

In an effort to limit the amount of soft tissue dissection at the fracture site, indirect reduction and minimally invasive fixation techniques have been developed to treat femoral and tibial fractures. These techniques, which do not rely upon anatomical reduction of the fracture fragments, are technically difficult. Correct limb length, axial alignment in the frontal and sagittal plane, and rotation must be assessed using means other than open reduction. In this technical note, some simple and effective intraoperative clinical examination and radiographic techniques to determine limb alignment are described. These include: the 'cable technique' for the determination of varus-valgus malalignment; the 'hypertension test','radiographic recurvatum sign','tibial plateau sign', and 'meterstick technique' for length analysis; and the 'hip rotation test', 'lesser trochanter shape sign', 'cortical step sign', and 'diameter difference sign' for rotational analysis. For each of the listed techniques, basic principles, technical instructions, limitations, advantages, and disadvantages are described.