Fluoroscopy is routinely used in trauma cases to evaluate alignment and reduction quality. Because conventional templating has a high mismatch rate, we sought to explore whether we could use intraoperative fluoroscopy while implanting the femoral stem. Sixty patients with Croft 3-4 coxarthrosis were included in this study. No preoperative templating was performed in either of the two groups. The final conformations of the stem sizes and positions were achieved freehand intraoperatively using anatomic landmarks. In the second group, after surgeons intraoperatively agreed on the final stem size, C-arm fluoroscopy images are obtained with the last rasp size before the stem implantation. The alignment of femoral stem according to the femoral canal, the lower leg discrepancy (LLD) and the lateral offsets were evaluated with X ray. The stem/endosteal areas at 2 cm above the trochanter minor (T+2) and 2 cm below the trochanter minor (T-2) and the deviation of the stem tip from the center of the femoral canal were evaluated in CT images. The stems that were implanted under fluoroscopic control filled the medullary cavity better at both the T+2 and T-2 levels. On fluoroscopy, in the control group, the malpositioning of the femoral stems were less, the centralizations were better, and the restorations of the lateral offset and LLD were more accurate. The use of fluoroscopy while rasping the femoral canal leads to proper alignment and press fitting of the stem and provides the opportunity to intraoperatively correct malpositionings of the stem.
Key words: Stem position, fluoroscopy, hip prosthesis , limb length discrepancy
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