The Compared Study about Femoral Stem Malalignment with or Without the Special Curved Rasp During DAA Total Hip Arthroplasty.

To investigate whether the application of a curved rasp on the femoral side is effective in reducing the incidence of stem malalignment in total hip replacement with direct anterior approach (DAA-THA), followed by the analysis of the independent risk factors affecting stem malalignment. Retrospective analysis was carried out covering 160 patients undergoing DAA-THA from January 2019 to December 2021, with Tri-Lock (BPS, Depuy) stem applied in all 113 patients were screened according to inclusion and exclusion criteria. The data of gender, age, body mass index, preoperative diagnoses, Dorr classification, FAR ratio, pelvic morphology ratio, WOMAC scores, were analyzed to explore the independent factors influencing the malalignment of the femoral prosthesis implantation. Then data of patients were divided into group A and group B according to whether the curved rasp was taken during the operation. The chi-square test was performed to compare the incidence of femoral stem malalignment between the two groups. There revealed two independent risk factors: BMI and FAR ratio that affected femoral stem malalignment. The increased BMI was associated with a higher probability of femoral stem malalignment (P<0.05), the probability of malalignment of femoral stem in FAR ratio<1 was 1.15 times higher than that in FAR>1(OR = 1.15, 95